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Molecular assessment of muscle health and function : The effect of age, nutrition and physical activity on the human muscle transcriptome and metabolom
Hangelbroek, Roland W.J. - \ 2017
Wageningen University. Promotor(en): Sander Kersten; Lisette de Groot, co-promotor(en): Mark Boekschoten. - Wageningen : Wageningen University - ISBN 9789463437103 - 205
muscles - age - nutrition - physical activity - transcriptomes - metabolomes - elderly - creatine - phosphocreatine - vitamin d - atrophy - spieren - leeftijd - voeding - lichamelijke activiteit - transcriptomen - metabolomen - ouderen - fosfocreatine - vitamine d - atrofie
Prolonged lifespan and decreased fertility will lead to an increased proportion of older adults in the world population (population aging). An important strategy to deal with population aging has been to promote healthy aging; not only to prevent mounting health care costs, but also to maintain independence and quality of life of older populations for as long as possible. Close to the opposite of the healthy aging is frailty. A major component of (physical) frailty is sarcopenia: age-related loss of muscle mass. Decreased muscle size and strength has been associated with a wide variety of negative health outcomes, including increased risk of hospitalization, physical disability and even death. Therefore, maintaining muscle size and strength is very important for healthy aging. Nutrition and physical activity are possible strategies to maintain or even improve muscle function with age.
The effect of nutrition, age, frailty and physical activity on the function of skeletal muscle is complex. A better understanding of the molecular mechanisms involved can provide new insights in potential strategies to maintain muscle function over the life course. This thesis aims to investigate these mechanisms and processes that underlie the effects of age, frailty and physical activity by leveraging the sensitivity and comprehensiveness of transcriptomics and metabolomics.
Chapter 2 and 3 describe the effects of age, frailty and resistance-type exercise training on the skeletal muscle transcriptome and metabolome. Both the transcriptome and metabolome show significant differences between frail and healthy older adults. These differences are similar to the differneces between healthy young men and healthy older adults, suggesting that frailty presents itself as a more pronounced form of aging, somewhat independent of chronological age. These age and frailty related differences in the transcriptome are partially reversed by resistance-type exercise training, in accordance with the observed improvement in muscle strength. Regression analysis revealed that the protocadherin gamma gene cluster may be important to skeletal muscle function. Protocadherin gamma is involved in axon guidance and may be upregulated due to the denervation-reinnervation cycles observed in skeletal muscle of older individuals. The metabolome suggested that resistance-type exercise training led to a decrease in branched-chain amino acid oxidation, as shown by a decrease in amino acid derived carnitines. Lastly, the blood metabolome showed little agreement with the metabolome in skeletal muscle, indicating that blood is a poor read-out of muscle metabolism.
We assessed the effect of knee immobilization with creatine supplementation or placebo on the skeletal muscle transcriptome and metabolome in chapter 4. Knee immobilization caused muscle mass loss and strength loss in all participants, with no differences between creatine and placebo groups. Knee immobilization appeared to induce the HDAC4-myogenin axis, which is primarily associated with denervation and motor neuron diseases. The metabolome showed changes consistent with the decreased expression of energy metabolism genes. While acyl-carnitine levels tended to decrease with knee immobilization, one branched-chain amino acid-derived acyl carnitine was increased after knee immobilization, suggesting increased amino acid oxidation.
Vitamin D deficiency is common among older adults and has been linked to muscle weakness. Vitamin D supplementation has been proposed as a strategy to improve muscle function among older populations. In chapter 5, supplementation with vitamin D (calcifediol, 25(OH)D) is investigated as nutritional strategy to improve muscle function among frail older adults. However, we observed no effect of vitamin D on the muscle transcriptome. These findings indicate the effects of vitamin D supplementation on skeletal muscle may be either absent, weak, or limited to a small subset of muscle cells.
Transcriptomic changes due to different forms of muscle disuse are compared in chapter 6 (primarily knee immobilization and bed rest). The goal was to determine the similarities and differences among various causes of muscle atrophy in humans (primarily muscle disuse). Both knee immobilization and bed rest led to significant changes in the muscle transcriptome. However, the overlap in significantly changed genes was relatively small. Knee immobilization was characterized by ubiquitin-mediated proteolysis and induction of the HDAC4/Myogenin axis, whereas bed rest revealed increased expression of genes of the immune system and increased expression of lysosomal genes. Knee immobilization showed the highest similarity with age and frailty-related transcriptomic changes. This finding suggests that knee immobilization may be the most suitable form of disuse atrophy to assess the effectiveness of strategies to prevent age-related muscle loss in humans.
The transcriptome and metabolome are incredibly useful tools in describing the wide array of biological systems within skeletal muscle. These systems can be modulated using physical activity (or lack thereof) as well as nutrition. This thesis describes some of these processes and highlights several unexplored genes and metabolites that may be important for maintaining or even optimizing muscle function. In the future, it may be possible to optimize both exercise and nutrition for each individual using these techniques; or even better, cheaper and less invasive alternatives.
Dietary patterns for healthier cognitive ageing
Berendsen, Agnes A.M. - \ 2017
Wageningen University. Promotor(en): Lisette de Groot; Edith Feskens, co-promotor(en): Ondine van de Rest. - Wageningen : Wageningen University - ISBN 9789463436014 - 190
meal patterns - feeding habits - aging - cognition - health - food supplements - dementia - nutritional intervention - elderly - elderly nutrition - nutrition and health - maaltijdpatronen - voedingsgewoonten - verouderen - kenvermogen - gezondheid - voedselsupplementen - dementie - maatregel op voedingsgebied - ouderen - ouderenvoeding - voeding en gezondheid
With ageing of our population and the accompanying increase in the number of people living with dementia, it is important to find modifiable risk factors to postpone the onset of cognitive decline. Diet has been proposed such a modifiable risk factor. To date, numerous studies have been conducted demonstrating a possible role of specific nutrients and foods in cognitive functioning. However, as people do not consume single nutrients, the research field has shifted towards studying dietary patterns in which synergistic effects of single nutrients and/or foods can be studied. The main aim of this thesis was to study the association of healthful dietary patterns with cognitive functioning. In addition, nutrient intake inadequacies were assessed and the potential to change dietary intake in older adults aged 65 years and older was studied.
Chapter 2 describes nutrient intake of 245 Dutch adults aged 65-80 years. We identified the contribution of nutrient dense foods, fortified foods and dietary supplements to the total intake of micronutrients. Nutrient density of foods was evaluated using the Nutrient Rich Food score 9.3. Nutrient intake inadequacies were observed for vitamin D, vitamin B6 and selenium. Conventional foods were the main source of vitamin D, vitamin B6 and selenium intake. Foods with the highest nutrient density contributed most to total vitamin B6 intake. In order to optimize nutrient intakes of elderly, combinations of natural food sources, fortified foods and dietary supplements should be considered.
Chapter 3 provides a systematic review of the literature on human studies up to May 2014 that examined the role of dietary patterns in relation to cognitive decline or dementia. The results demonstrate that better adherence to a Mediterranean diet was associated with less cognitive decline, dementia or Alzheimer’s Disease (AD) in four out of six cross-sectional studies, six out of 12 longitudinal studies, one trial and three meta-analyses. Other healthy dietary patterns, among which the Healthy Diet Indicator, have shown to be associated with reduced cognitive decline and/or a reduced risk of dementia in all six cross-sectional studies and six out of eight longitudinal studies. The conclusion of this literature review was that more conclusive evidence is needed to come to more targeted and detailed dietary guidelines to prevent or postpone cognitive decline.
In chapter 4 the association between the Healthy Diet Indicator (HDI) and cognitive functioning in older adults from three different cohort studies was investigated. The cohorts included in total 21,837 subjects from Europe (SENECA and the Rotterdam Study [RS]) and the Unites States (Nurses’ Health Study [NHS]). Cognitive functioning was measured using the Mini-Mental State Examination (MMSE) in SENECA and RS, and the Telephone Interview for Cognitive Status (TICS) in NHS. In all three cohorts, the HDI was not significantly associated with cognitive decline, nor with cognitive function.
In chapter 5 the association of long-term adherence to the Dietary Approaches to Stop Hypertension (DASH) diet with cognitive function and decline in older American women was examined. A total of 16,144 women from the Nurses’ Health Study, aged ≥70 years, who underwent cognitive testing a total of 4 times by telephone from 1995-2001 (baseline), with multiple dietary assessments between 1984 and the first cognitive exam were studied. Greater adherence to long-term DASH score was significantly associated with better average global cognition, verbal memory and TICS score at older ages, but not with cognitive decline.
In chapter 6, the same cohort as in chapter 5 was studied to examine the association between long-term adherence to a recently developed Mediterranean-DASH Intervention for Neurodegenerative Delay (MIND) diet with cognitive function and decline. Higher MIND diet scores were associated with better verbal memory at older ages, but not with cognitive decline over 6 years in global cognition, verbal memory or TICS.
Chapter 7 provides an overview of the NU-AGE (NUtrients and AGEing) dietary intervention study. The NU-AGE study is a randomized one-year intervention in 1,250 apparently healthy, independently living European subjects aged 65 to 80 years. Subjects were randomised into either the intervention group or the control group. Participants in the intervention group received dietary advice aimed at meeting the dietary recommendations of the ageing population. At the start of this thesis, the NU-AGE study was the first dietary intervention investigating the effect of a whole diet and providing targeted dietary recommendations for optimal health and quality of life in apparently healthy European elderly.
In chapter 8, we evaluated if the NU-AGE intervention could be effective to shift the dietary intake of apparently healthy older adults aged 65-80 years living in Italy, the UK, the Netherlands, Poland, and France towards a more healthful diet. The NU-AGE index was created to assess adherence to the NU-AGE diet. At baseline and after one-year follow-up dietary intake was assessed by means of 7-day food records. In total, 1,296 participants were randomized and 1,145 participants completed the intervention (571 in intervention group, 570 in control group). After one-year follow-up, the intervention group improved mean intake of 13 out of 16 dietary recommendations of the NU-AGE diet (p<0.05) with a significant increase of the total NU-AGE index, compared to the control group (mean change in NU-AGE index 21.3±15.9, p<0.01). The NU-AGE dietary intervention, based on dietary recommendations for older adults, may be a feasible strategy to improve dietary intake in an ageing European population.
Chapter 9 shows the results of the NU-AGE parallel randomized dietary intervention study on cognitive functioning in the Dutch NU-AGE subpopulation, including 252 older adults aged 65-80 years (123 intervention, 129 control). The primary outcome was one-year change in global cognition and in four cognitive domains as measured through a comprehensive neuropsychological test battery. Comparing the intervention with the control group, there was no effect of the intervention on cognitive functioning.
In chapter 10 the main findings of this thesis were summarized and a reflection on methodological aspects was given. When grading the reported associations in previous studies and studies in this thesis, it was concluded that there is probable evidence for a role of the Mediterranean diet on cognitive functioning. For the DASH and MIND diet there is a possible link with cognitive functioning; for the HDI and the NU-AGE diet there is no sufficient evidence yet to conclude that there is a relation with cognitive functioning. Not only is there a need for well-designed intervention and prospective studies, we also call for communication strategies to the general public about the consumption of healthier diets to not only impact cardiovascular but also potentially impact brain health as many individuals will face progressive cognitive decline in the near future.
Understanding heterogeneity in decision-making among elderly consumers: the case of functional foods
Zanden, Lotte D.T. van der - \ 2017
Wageningen University. Promotor(en): Hans van Trijp, co-promotor(en): Ellen van Kleef; Rene de Wijk. - Wageningen : Wageningen University - ISBN 9789463431439 - 161
voedselopname - ouderen - voedselsamenstellingtabellen - voedselverrijking - ouderenvoeding - leeftijdsgroepen - marketing - marketing van voedingsmiddelen - ziekenhuisdiëten - besluitvorming - consumenten - voedselconsumptie - food intake - elderly - food composition tables - food enrichment - elderly nutrition - age groups - food marketing - hospital diets - decision making - consumers - food consumption
The population of elderly has grown considerably over the past few decades, due to reduced birth rates and increased life expectancy. Old age is, however, still associated with a higher incidence of various health conditions that pose a threat to quality of life and result in high healthcare costs. Various products and services could help elderly to stay active and healthy for longer if they were adopted, such as mobility aids, home modifications and functional foods. A key challenge is to position products and services like these on the market in such a way that elderly can see their value and will start using them. In doing this, it is crucial to know what elderly need and to understand how they make decisions. This thesis therefore aims to provide a deeper understanding of decision-making among elderly consumers. It does so using functional foods as an example, and concentrates on answering the following research questions: 1) Which types of wants, inferences and intentions characterize the elderly consumer population? 2) What are relevant ways to distinguish between elderly consumers? and 3) How can elderly consumers be motivated to form consumption intentions for products and services aimed at promoting their wellbeing?
An experience-sampling paradigm shows that there are age-related differences in both desires (i.e. wants), such as the desire for food, and goals, such as the goal to work (i.e. intentions), but not in the way these wants and intentions interact with each other (Chapter 2). Young and old consumers experience the same types of conflict between their wants and intentions. The extent of conflict does change with age however, such that older adults experience conflict less often and less strongly than younger adults. This age-related difference can be partly explained by the way in which consumers perceive the time they have left in their lives. Those who perceive time as limited, experience more conflict. Zooming in on product-specific decision-making, a series of focus groups indicates that elderly consumers overall want to use healthy products that they use frequently as a basis for enrichment with protein (Chapter 3). Most elderly do not display intentions to purchase and use such products, however, either because they do not feel the need to use functional foods or because they hold various negative inferences regarding functional foods, such as a high price or bad taste. Importantly, elderly consumers differ strongly in their wants, inferences and intentions, suggesting that segmentation of this population is warranted.
A narrative review reveals that there are various ways to segment the elderly consumer population, for example based on age, future time perspective or purchase behaviour, and every approach has its strengths and weaknesses (Chapter 4). Based on the objectives of a segmentation approach one can, however, make an informed decision regarding which segmentation base to use. In the functional food market, elderly consumers may best be segmented using a segmentation base on the food or product level (i.e. rather than the person level) that results in segments in which consumers have similar needs and wants, for example the attributes benefits that consumers seek. A segmentation study shows that using such a segmentation base results in segments that provide concrete instructions for the development of functional foods (Chapter 5). The resulting segments of elderly have unique preferences that do not necessarily reflect those of the average elderly consumer and thereby provide useful insights that can help increase our understanding of elderly consumers.
Segmentation also provides a basis for tailoring products to the needs and wants of elderly consumers. A segmentation study illustrates that such tailoring can increase elderly consumers’ willingness to try protein-enriched foods for the first time (i.e. trial purchase), as well as their willingness to use such products on a more regular basis (i.e. repeat purchase) (Chapter 5). For a small group of elderly, tailoring proves to be ineffective, however, as they categorically reject all types of protein-enriched foods presented to them. These elderly are relatively uninterested in the concept of functional foods, which may be due to negative inferences surrounding such products. Overcoming the activation of such negative inferences may be useful in motivating elderly consumers to use protein-enriched foods. A field study in a hospital setting shows that the implementation of a verbal prompt intervention that motivates consumers to make decisions without much can increase the consumption of protein (Chapter 6). By understanding and capitalizing on cognitive biases in human decision-making, interventions like these can motivate consumers to form consumption intentions even when they hold negative inferences about products or services.
Overall, this thesis shows that although elderly consumers share an age bracket they are strongly heterogeneous in their wants, inferences and intentions. This heterogeneity is robust, as it can even be observed when zooming in on decision-making regarding a specific product category (i.e. protein-enriched foods). Our understanding of the elderly consumer population increases by studying this heterogeneity, as it provides insights beyond those that apply to the group of elderly that reflect the average. In studying heterogeneity, it pays off to focus on bases that are predictive of behaviour while demographic characteristics like age provide only few insights. Industry and health institutions can also benefit from an increased understanding of the composition of the elderly population and how they make decisions. Such understanding may provide them with concrete instructions for the development and commercialization of products and services for this growing group of consumers.
How to measure health improvement? : assessment of subtle shifts in metabolic phenotype
Fazelzadeh, Parastoo - \ 2017
Wageningen University. Promotor(en): Sander Kersten; John van Duynhoven, co-promotor(en): Mark Boekschoten. - Wageningen : Wageningen University - ISBN 9789463430739 - 187
health promotion - improvement - measurement - metabolic profiling - elderly - obesity - microarrays - rna - peripheral blood mononuclear cells - gezondheidsbevordering - verbetering - meting - metabolische profilering - ouderen - obesitas - perifere mononucleaire bloedcellen
Human health is impacted by a complex network of interactions between biological pathways, mechanisms, processes, and organs, which need to be able to adapt to a continuously changing environment to maintain health. This adaptive ability is called ‘phenotypic flexibility’. It is thought that health is compromised and diseases develop when these adaptive processes fail. As the product of interactions between several factors such as genetic makeup, diet, lifestyle, environment and the gut microbiome, the ‘metabolic phenotype’ provides a readout of the metabolic state of an individual. Understanding these relationships will be one of a major challenges in nutrition and health research in the next decades. To address this challenge, the development of high-throughput omics tools combined with the application of elaborate statistical analyses will help characterize the complex relationship of (bio) chemicals in human systems and their interaction with other variables including environment and lifestyle to produce the measured phenotype. An important aim of this thesis was to identify phenotype shifts by looking at effect of prolonged resistance-type exercise training on skeletal muscle tissue in older subjects and the possible shift toward the features of younger subjects as a reference for a healthier phenotype. A second aim was to identify phenotype shifts by looking at the response to a challenge in obese subjects and the possible shift toward lean subjects as a reference for a healthier phenotype.
Chapter 2 and 3 of this thesis show how the significant remaining plasticity of ageing skeletal muscle can adapt to resistance-type exercise training. The data indicate that frail and healthy older subjects have two distinct phenotypes according to the skeletal muscle tissue metabolite profiles and that exercise training shifts aged muscle towards a younger phenotype. We showed that the effect of exercise on amino acid derived acylcarnitines (AAAC’s) in older subjects points towards decreased branched chain amino acid catabolism, likely due to compromised activation of the branched chain α-keto acid hydrogenase (BCKDH) complex. Furthermore, we found that the protocadherin gamma gene cluster might be involved in aged-muscle denervation and re-innervation. Finally, plasma was found to be a poor indicator of muscle metabolism, emphasizing the need for direct assessment of metabolites in muscle tissue.
Chapter 4 of this thesis examines whether a mixed meal challenge response provides a readout for a shift in phenotype upon weight loss in obese male subjects. We concluded that weight loss moderately affects the mixed meal challenge response of both plasma metabolome and transcriptome of peripheral blood mononuclear cells in obese subjects. Measurements at the fasted and postprandial state also provide us with a different type of information.
In Chapter 5 it is demonstrated that the global testing of pathways could provide a concise summary of the multiple univariate testing approach used in Chapter 4. In Chapter 6 it is discussed how the findings of this thesis increase our understanding of how to measure phenotypic flexibility as a proxy of health. In this thesis it is shown that the correlations between tissue and plasma metabolites are rather weak, emphasising the need to perform organ-specific studies. Availability of less invasive/painful sampling techniques and the use of small amounts of tissue would enable larger scale human studies on adipose tissue and skeletal muscle to more accurately define phenotypical shifts due to diet or lifestyle interventions. With respect to the assessment of phenotypical flexibility by omics approaches, significant complications can be expected in trying to relate plasma metabolism to PBMC gene expression. Organ-focussed approaches that integrate multiple omics levels using system biology approaches are considered to be a lot more promising.
Undernutrition management and the role of protein-enriched meals for older adults
Ziylan, Canan - \ 2016
Wageningen University. Promotor(en): Lisette de Groot; Stefanie Kremer; Annemien Haveman-Nies. - Wageningen : Wageningen University - ISBN 9789462579323 - 148
elderly - elderly nutrition - undernutrition - enrichment - protein - eating patterns - feeding behaviour - meals - nursing homes - ouderen - ouderenvoeding - ondervoeding - verrijking - eiwit - eetpatronen - voedingsgedrag - maaltijden - verpleeghuizen
Undernutrition is a major health problem in the growing elderly population. It is estimated that one in ten Dutch community-dwelling older adults is suffering from undernutrition, and one in three Dutch older adults who receive home care. Undernutrition may lead to many negative consequences, ranging from fatigue and falls to impaired immune function and death. This makes undernutrition an obvious target for preventive measures.
Undernutrition can be defined as “a state of nutrition in which a deficiency or excess (or imbalance) of energy, protein, and other nutrients causes measurable adverse effects on tissue/body form (body shape, size and composition) and function, and clinical outcome”. In addition, it is often described as protein energy malnutrition. Adequate protein intake may to some extent prevent and reverse this process. However, throughout ageing, it becomes increasingly difficult to reach adequate protein intake due to higher protein needs and lower protein intakes. Finding solutions to assist older adults in reaching their optimal protein intake is necessary.
In our overall research project, we considered 1.2g protein per kg weight per day (g/kg/d) as adequate protein intake. In Dutch community-dwelling older adults, protein intake is around 1.0 g/kg/d, implying room for improvement. However, it is possible that many of these older adults deal with physiological changes, medical conditions, and physical and mental limitations that impair their appetite and food provision. For these older adults with higher protein needs, merely recommending that they eat more would not be realistic. It would be more realistic to explore strategies that increase protein intake without having to increase food intake. This calls for the exploration of instruments that match the needs and preferences of older adults: protein-enriched regular products.
One particular group that can be identified as a target group for such products, are older adults who receive home care. Undernutrition prevalence is high in this group, which may be explained by their health problems that led to this dependence on home care. Likewise, many of these older adults also depend on meals-on-wheels. These meals-on-wheels recipients, regardless of whether they receive home care or not, often risk undernutrition too. In both these (overlapping) care-dependent groups, difficulties in adhering to energy and protein recommendations can be discerned. For this reason, enriching the readymade meals that these older adults receive may contribute to the prevention of protein undernutrition by increasing protein intake while keeping food intake the same. Here, protein enrichment instruments can be used to prevent undernutrition, but only when implemented in a timely manner. Adequate undernutrition management systems are therefore necessary to facilitate timely intervention, ensuring that the developed protein-enriched meals are actually offered and effective. For this reason, the overall aim of our research project was to gain insight into the current state of undernutrition management in community-dwelling older adults in the Netherlands and explore the role of protein-enriched regular products as a supportive instrument in protein undernutrition management.
In Study 1 (chapter 2) we explored the experiences of 22 Dutch nutrition and care professionals and researchers with undernutrition awareness, monitoring, and treatment among community-dwelling older adults. This qualitative study among, for example, dietitians, general practitioners, nurse practitioners, and home care nurses provided insight into the current bottlenecks within the existing undernutrition management guidelines. In these telephone interviews, these experts also discussed the current dietary behaviour problems of older adults and their impact on undernutrition risk. The experts’ experiences implied that undernutrition awareness is limited, among both older adults and care professionals. In addition, the interviewees were unclear about which professionals are responsible for monitoring and which monitoring procedures are preferred. The dietitians feel that they become involved too late, leading to decreased treatment effectiveness. In general, the interviewees desired more collaboration and a coherent and feasible allocation of responsibilities regarding undernutrition monitoring and treatment. This implied that the available guidelines on undernutrition management require more attention and facilitation.
In the following mixed-methods study (chapter 3), with interviews, we qualitatively explored the dietary behaviour and undernutrition risk of 12 Dutch elderly meals-on-wheels clients, one of the largest at-risk groups. We followed up on this information by quantifying the topics that emerged from the qualitative exploration of experienced bottlenecks in performing adequate dietary behaviour. For this, we used a survey among 333 meals-on-wheels clients. The interviews with elderly meals-on-wheels clients made clear that they have fixed and habitual eating patterns, while at the same time their appetite had decreased throughout the years. This was confirmed by the survey finding that regular portion size meals were perceived as too large by the oldest group aged over 75y. In addition, as the professionals suggested earlier, the interviewed elderly clients indeed showed limited awareness of undernutrition risk. Simultaneously, the survey showed that almost one in four elderly meals-on-wheels clients was undernourished. These findings led to the conclusion that staying close to the identified dietary habits may facilitate small yet effective modifications within these habits to prevent inadequate nutritional intake. Still, the limited awareness of undernutrition risk was expected to play a limiting role in whether clients believe they need dietary modifications. Consequently, informing them about this need could facilitate their motivation to implement modifications.
After learning about the general dietary behaviour of these older adults, we used this information for Study 3 (chapter 4). We developed two kinds of protein-enriched readymade meals that are in line with the needs and preferences of older adults: one of regular size (450g) and one of reduced size (400g). We tested these meals in a lab setting in 120 community-dwelling older adults in a single-blind randomised crossover trial. One day a week at lunchtime, for four weeks, participants had to consume and evaluate a readymade meal. Overall, regardless of portion size, the protein-enriched meals led to higher protein intakes in vital older adults in a lab setting during lunch. In this crossover study, the participants liked the protein-enriched meals and the regular meals equally. However, we did not find the expected lower ratings of satiety after the reduced-size meals, while one reduced-size enriched meal and another regular-size enriched meal led to higher ratings of subsequent satiety. This higher satiety in the enriched meals could lead to compensational behaviour on the remainder of the day.
After establishing that the protein-enriched meals were effective and acceptable in the lab setting, we moved to the homes of older adults to test the meals in a longer-term study in Study 4 (chapter 5). In this double-blind randomised controlled trial of two weeks, we also included protein-enriched bread to assess whether both this bread and the meals could increase daily protein intake to 1.2g/kg/d in 42 community-dwelling older adults to reach optimal protein intake. We found that the enriched products again led to higher protein intakes and a high liking. The mean protein intake per day was 14.6g higher in the intervention group, which amounted to a protein intake of 1.25g/kg/d, compared with 0.99g/kg/d in the control group. In addition, the meals scored 7.7 out of 10, while the bread scored 7.8 out of 10, which both were comparable with their regular counterparts. Lastly, we found no negative effect of compensational behaviour throughout the day. These promising findings indicated that we achieved a good match between older adults’ needs and preferences regarding protein intake.
In the general discussion of this thesis (chapter 6), we combined our learnings from the four studies to reflect on protein undernutrition management in community-dwelling older adults and the possible role of protein-enriched regular products. We have discussed a conceptual framework consisting of three wheels of protein undernutrition management. In the first wheel regarding awareness, we proposed that limited awareness of adequate nutrition and body composition forms the largest bottleneck in undernutrition management. When this awareness is generated among both older adults and professionals, it will benefit the second wheel of monitoring. Here, we argued that a policy and the actual facilitation of that policy are required for this monitoring to succeed. When the monitoring is performed adequately, in the third wheel, the appropriate treatment can be carried out. We discussed that personalisation and evaluation of this treatment are important conditions. All in all, the public health implications that we have discussed on the basis of our findings can be summarised by the three key messages that could help us ace in adequate protein undernutrition management: address awareness in both older adults and professionals, facilitate continuous collaboration between professionals, and offer protein-enriched products expediently.
Nutritional interventions to preserve skeletal muscle mass
Backx, Evelien M.P. - \ 2016
Wageningen University. Promotor(en): Lisette de Groot; L.J.C. van Loon. - Wageningen : Wageningen University - ISBN 9789462579149 - 158
musculoskeletal system - nutritional intervention - skeletal muscle - vitamin d - creatine - leucine - nandrolone - protein intake - young adults - elderly - overweight - athletes - preservation - skeletspierstelsel - maatregel op voedingsgebied - skeletspier - vitamine d - nandrolon - eiwitinname - jongvolwassenen - ouderen - overgewicht - atleten - behoud
Muscle mass is the main predictor for muscle strength and physical function. The amount of muscle mass can decline rapidly during periods of reduced physical activity or during periods of energy intake restriction. For athletes, it is important to maintain muscle mass, since the loss of muscle is associated with decreased muscle strength, decreased physical performance and a longer recovery period. In the older and more clinically compromised populations, the consequences of muscle loss can substantially impact metabolic health, physical functioning, quality of life and mortality rates. In this thesis, the effects of different nutritional interventions on the preservation of muscle mass are being evaluated.
Vitamin D deficiency (serum 25-hydroxyvitamin D or 25(OH)D) has been associated with increased muscle loss and reduced muscle strength. In chapter 2, we identified seasonal changes in 25(OH)D concentration in elite athletes. We observed that 25(OH)D concentrations were highest at the end of summer (113±26 nmol/L), and lowest at the end of winter (78±30 nmol/L). Athletes that had a sufficient 25(OH)D concentration (>75 nmol/L) at the start of the study, still had a high risk (20%) of being deficient (<50 nmol/L) in late winter. Thus, a sufficient 25(OH)D concentration in summer does not guarantee a sufficient status in winter. In chapter 3, we assessed 25(OH)D concentrations in 128 highly-trained athletes and found that 70% had a deficient or insufficient 25(OH)D concentration at the end of the winter season. Supplementation with 2200 IU/d vitamin D resulted in a sufficient 25(OH)D concentration in 80% of the athletes after 12 months and was therefore a better dosage to improve 25(OH)D concentration than 400 or 1100 IU/d.
In the following chapters, we assessed the effects of creatine supplementation (chapter 4), leucine supplementation (chapter 5) and nandrolone administration (chapter 6) on the preservation of muscle mass during a short period of muscle disuse. For all of these compounds there is prior evidence for their efficacy in augmenting muscle mass and strength gains in combination with resistance-type exercise training and all have been suggested to attenuate the loss of muscle mass during a period of muscle disuse. During 7 days of single-leg immobilization, muscle mass decreased by ~6% and muscle strength decreased by ~8%. Surprisingly, none of the tested compounds attenuated the loss of muscle mass during 7 days of single-leg immobilization in healthy, young men.
In chapter 7, we performed a fully controlled dietary intervention to assess the impact of a high protein intake on the preservation of lean body mass during 12 weeks of energy intake restriction. Sixty-one overweight and obese men and women were randomly assigned to either a high protein diet (1.7 g/kg/d) or a normal protein diet (0.9 g/kg/d) during 12 weeks of 25% energy intake restriction. During the dietary intervention, subjects lost 9±3 kg body weight with a concomitant 2±2 kg decline in lean body mass with no differences between the two intervention groups. Thus, increasing protein intake above habitual intake levels (0.9 g/kg/d) did not preserve lean body mass during a period of energy intake restriction.
Finally, in chapter 8 we reflected on the main findings described in this thesis. In this chapter, we point out that the populations studied were all healthy and well-nourished. We conclude that in these populations, additional creatine, leucine and protein beyond habitual intakes did not preserve muscle mass. Older and/or malnourished individuals might be more responsive to these nutritional interventions. Future research could also focus on the combined effects of two or more nutritional compounds during disuse that are known to affect different mechanisms. Moreover, we speculate that the tested nutritional compounds could be effective in accelerating the regain of muscle mass and strength after a period of muscle loss. However, it should be noted that muscle loss during disuse occurs at a rate that is several-fold greater than muscle (re)gain during resistance type exercise training. Therefore, it is imperative that we continue our endeavors to identify nutritional or pharmaceutical compounds or exercise mimetics that may help to prevent or attenuate disuse atrophy.
Older adults, mealtime-related emotions, and functionalities : tailoring protein-enriched meals
Uijl, Louise C. den - \ 2016
Wageningen University. Promotor(en): Kees de Graaf, co-promotor(en): Stefanie Kremer; Gerry Jager. - Wageningen : Wageningen University - ISBN 9789462578920 - 178
meals - emotions - elderly nutrition - elderly - smell - food preferences - protein - proteins - questionnaires - young adults - chocolate - maaltijden - emoties - ouderenvoeding - ouderen - reuk - voedselvoorkeuren - eiwit - eiwitten - vragenlijsten - jongvolwassenen - chocolade
Background and aim
Dietary proteins are of special interest for the heterogeneous group of older adults, since these people do not always have an adequate protein intake. When protein-rich products are better aligned with the requirements of older persons, an adequate nutrient intake is more likely. In this thesis we therefore explored two approaches for tailoring protein-enriched meals to older consumer subgroups; emotion-based and functionality-based. We expected a better ‘product-cluster fit’ (i.e. a more positive meal experience) when the clusters’ meal associations are congruent to their mealtime expectations.
We conducted an online survey in which vital community-dwelling older adults (n=392) reported their mealtime-related emotions and mealtime functionality. Using a hierarchical clustering analysis we described clusters within our population. Subsequently, we explored the extent to which the expectations of these clusters can be applied for the development of tailored protein-enriched meals. For the emotion-based approach, we conducted two central location tests (CLTs, n=461) to explore older adults’ food-evoked emotions. For the functionality-based approach we conducted in-depth interviews in order to get further insights regarding functional mealtime expectations and attitudes towards proteins and protein-enrichment. Based on the latter insights we tailored PE meal concepts to two functionality-based segments. In a final home-use test, the members of the functionality-based segments (n=91) prepared and evaluated the tailored PE meal concepts.
The emotion-based approach resulted in four clusters; pleasurable averages, adventurous arousals, convivial indulgers, and indifferent restrictives. These emotions that these segments associated with their mealtimes varied along the two dimensions valence and arousal. However, from both CLTs we learned that the variation in valence-arousal as observed for mealtime-related emotions was not observed for emotions related to actual foods. The latter makes it challenging to identify products that evoke emotions congruent to the mealtime expectations of the emotion-based clusters.
With regard to the functionality-based approach, we encountered three clusters; physical nutritioners, cosy socialisers, and thoughtless averages. The cosy socialisers value the social interactions and cosiness during their mealtimes, whereas the physical nutritioners focus more on the health and nutrient aspects of meals. Thoughtless averages have the least distinctive mealtime expectations. We translated these functional mealtime expectations into two PE meal concepts; one tailored to cosy socialisers and one tailored to physical nutritioners. These meal concepts were well-accepted by the participants. However, congruency between mealtime expectations and functional meal associations did not result in a better ‘product-cluster fit’.
Given the challenge to identify congruency between the meal associations and the mealtime expectations of the emotion-based clusters, we consider the emotion-based approach to be not yet actionable enough as a basis for tailoring PE products to older consumers. In contrast, the functionality-based approach appeared to be more promising, since the functional meal expectations could be translated to well-accepted tailored PE meal concepts. However, the effectivity of our functionality-based approach was not yet confirmed in this thesis, since congruency between functional meal associations and functional meal expectations did not necessarily result in a better ‘product-cluster fit’. Future studies, focussing on e.g. other meal types, are recommended to further explore mealtime functionality as a basis for tailoring PE meals to older consumer subgroups.
Cater with Care : impact of protein-enriched foods and drinks for elderly people
Beelen, J. - \ 2016
Wageningen University. Promotor(en): Lisette de Groot; Frans Kok, co-promotor(en): Nicole de Roos. - Wageningen : Wageningen University - ISBN 9789462578814 - 142 p.
undernutrition - hospital catering - hospitals - protein - elderly - protein intake - food - beverages - diet studies - dietetics - dietitians - randomized controlled trials - ondervoeding - ziekenhuiscatering - ziekenhuizen - eiwit - ouderen - eiwitinname - voedsel - dranken - dieetstudies - diëtetiek - diëtisten - gestuurd experiment met verloting
Protein undernutrition is a major health concern for older adults, especially for those who are ill. There is growing consensus for a protein intake target of 1.2 - 1.5 gram per kg bodyweight per day (g/kg/d) for these older adults. However, this target is not reached by the majority of older adults. Therefore, more effective and novel strategies to increase protein intake are warranted, including the use of protein-enriched foods and drinks. This thesis evaluated the impact of the developed protein-enriched foods and drinks on protein intake and physical performance among older adults. The studies in this thesis were done as part of the Cater with Care® project; a collaboration between the university, care organizations, and partners from the food industry. The industrial partners developed the products, focusing each on different product categories: Carezzo Nutrition developed bread, pastry, and fresh juices and soups; The Kraft Heinz Company focused on long shelf-life and convenience foods; and the Veal Promotion Foundation produced veal meat.
To fit the products to the needs of the target group, interviews with undernourished older adults (at home or hospitalized) and with dietitians were conducted (chapter 2). These interviews showed that undernutrition awareness is low among older adults. To treat undernutrition by changing their eating habits, older adults need to be aware of their health problem, they need to be willing to change, and they need to be able to understand and implement the dietitian’s advices. This process takes time while undernutrition should be treated immediately. For immediate treatment, enriched products could be used, without first creating awareness. According to the interviewees, enriched products should fit within older adults’ eating habits, and have small portion sizes.
To gain insights in food choices of hospitalized older adults (65 years and older) an observational study was conducted. In this study, energy and protein intakes of 80 hospitalized older patients at low and high risk of undernutrition were assessed (chapter 3). Patients who received an energy- and protein-rich menu, because of their risk of undernutrition, were better able to reach the protein and energy targets than patients with a low risk of undernutrition receiving a standard menu. Based on these results we proposed that all hospitalized older adults – both at low and high risk of undernutrition – should receive an energy- and protein-rich menu.
Subsequently, a pilot study was done in a care home and a rehabilitation center with the aim to explore the potential of the developed protein-enriched products to increase protein intake (chapter 4). Participants did not compensate their consumption of regular protein-rich foods (e.g. dairy, cheese) upon the introduction of protein-enriched foods and drinks. The 22 institutionalized elderly (mean age 83 years) consumed 12 gram protein per day more than they did before the intervention. Consequently, more people met the protein target of 1.2 g/kg/d than before the intervention. We concluded that protein-enriched products enabled institutionalized elderly to reach protein intake targets. Furthermore, we gained valuable feedback to improve the assortment of protein-enriched products for the effectiveness study.
In the final study, effects of the protein-enriched products on protein intake and physical performance were studied in a randomized controlled trial during hospitalization and subsequent recovery at home. During the hospital period in which 147 older patients participated, patients that received protein-enriched products increased their protein intake compared to the control group that already received a protein-rich hospital menu (chapter 5). As a result, 79% of the intervention group reached a protein intake of 1.2 g/kg/d, compared to 48% of the control group. Finally, effects of the protein-enriched products were tested at home, for a longer period (chapter 6). Half of the hospital phase participants (n = 75) continued the intervention at home for 12 weeks. The protein-enriched products were successfully implemented in the daily menu of the older adults: the intervention group had a higher average protein intake (1.5 ± 0.6 g/kg/d) than the control group (1.0 ± 0.4 g/kg/d) during the 12-week intervention period. Seventy-two percent of the intervention group reached a protein intake of 1.2 g/kg/d during the 12-week intervention, compared to 31% of the control group. Protein intake of the intervention group was mainly increased by the following protein-enriched products: bread, dairy drinks, dairy desserts, soups, and fruit juices. However, despite the successful improvement of protein intake, we found no added value on physical performance in the first 6 months after hospitalization.
It was concluded that with the protein-enriched familiar foods and drinks, we have a feasible, acceptable, and appetizing long-term strategy to increase protein intake of older adults in various settings. We envisage a beneficial role of these protein-enriched products in combination with physical activity in older adults with lower protein intakes.
Wonen op de zorgboerderij : dag en nacht profiteren van de kwaliteiten van de boerderij
Ferwerda-van Zonneveld, R.T. ; Hassink, J. ; Migchels, G. ; Veen, E.J. ; Meulen, H.A.B. van der; Teenstra, E.D. - \ 2015
Wageningen : Wageningen UR - 51
zorgboerderijen - sociale zorg - multifunctionele landbouw - huisvesting op het platteland - leefvormen - financieren - doelgroepen - agrarische bedrijfsvoering - dagopvang - ouderen - gehandicapten - jeugd - social care farms - social care - multifunctional agriculture - rural housing - living arrangements - financing - target groups - farm management - day care - elderly - people with disabilities - youth
Deze brochure gaat in op varianten van wonen op een zorgboerderij aan de hand van concrete voorbeelden.
Alleen sterkere smaak verhoogt eetlust niet
Doets, E.L. ; Kremer, S. - \ 2015
Resource: weekblad voor Wageningen UR 10 (2015)6. - ISSN 1874-3625 - p. 8 - 8.
ondervoeding - eiwitdepletie - ouderen - voedselvoorkeuren - voedselkwaliteit - productontwikkeling - smaak - voedselverpakking - voeding - voedingsonderzoek - ouderenvoeding - undernutrition - protein depletion - elderly - food preferences - food quality - product development - taste - food packaging - nutrition - nutrition research - elderly nutrition
Vijf tot tien procent zelfstandige ouderen is ondervoed. Ouderen waarderen voeding waarschijnlijk beter als verschillende aspecten zoals textuur, smaak en uiterlijk tegelijkertijd worden verbeterd. Dit schrijven Esmée Doets en Stefanie Kramer, onderzoekers bij Food & Biobased Research, in een overzichtsstudie in het tijdschrift Food Quality and Preference.
Langer fit met beter eten
Smit, A. ; Groot, C.P.G.M. de; Kremer, S. ; Ziylan, C. ; Peppelenbos, H.W. - \ 2015
WageningenWorld (2015)1. - ISSN 2210-7908 - p. 10 - 15.
ouderen - ouderenvoeding - voeding en gezondheid - ondervoeding - voedingstoestand - eiwitrijke voedingsmiddelen - voedselverrijking - voedselconsumptie - gezondheidsbevordering - elderly - elderly nutrition - nutrition and health - undernutrition - nutritional state - protein foods - food enrichment - food consumption - health promotion
Ouderen die zelfstandig thuis wonen, lopen het risico ondervoed te raken. Wageningen UR onderzoekt hoe dat is te voorkomen met producten en maaltijden die verrijkt zijn met extra eiwit. Maar hoe breng je die op de markt? De meeste ouderen voelen zich niet oud en zijn zich totaal niet bewust van hun voedingsstatus.
Healthy aging through a healthy diet : never too old to eat healthy?!
Jankovic, N. - \ 2015
Wageningen University. Promotor(en): Ellen Kampman; Edith Feskens; Lisette de Groot, co-promotor(en): Anouk Geelen. - Wageningen : Wageningen University - ISBN 9789462572508 - 159
voeding en gezondheid - gezondheidsvoedsel - ouderen - dieetrichtlijnen - eetpatronen - analytische methoden - ziektepreventie - ouderenvoeding - nutrition and health - health foods - elderly - dietary guidelines - eating patterns - analytical methods - disease prevention - elderly nutrition
Background: The world’s population is aging and with it the prevalence of chronic diseases, especially cardiovascular diseases and cancer, increases. A long lasting life is envisaged without the burden of disease. Therefore, current research focuses on risk factors, such as a healthy diet, which may decrease the occurrence of chronic diseases even at advanced age. Earlier studies, examining the role of a healthy diet in the elderly, applied different analysis strategies. In consequence, comparability across studies is limited and prevent an overall conclusion on the role of a healthy diet in elderly.
Methods and subjects: Eleven prospective cohort studies among elderly people (N=396,391) from Europe and the United States, collaborating in the CHANCES consortium, were analysed. Most cohorts eligible for our analysis, assessed diet once at baseline. Therefore, we first assessed the stability of dietary patterns, derived with reduced rank regression (RRR), in the Zutphen Elderly Study. In the remainder of this thesis, healthy diets were defined based on the 2003 World Health Organization (WHO) “nutrient intake goals” and the 2007 World Cancer Research Fund/American Institute for Cancer Research (WCRF/AICR) food group recommendations. The recommendations were operationalized, using the Healthy Diet Indicator (HDI) and the WCRF/AICR diet score. The association between a healthy diet and risk of all-cause mortality and CVD mortality, was studied using the WHO recommendations, which aim at the prevention of chronic diseases in general. The cancer specific WCRF/AICR recommendations were applied to study the association between a healthy diet and cancer risk. Diet disease associations were assessed in each cohort separately, using Cox-proportional hazards regression. Cohort specific hazard ratios (HR) were pooled by random effects meta-analysis.
Results: The results of the Zutphen Elderly Study showed that dietary patterns, derived by RRR, remained stable over a period of five years. In the CHANCES project a total of 84,978 person years were accumulated, during a median follow-up time ranging between 7 and 15 years across cohorts. An increase of 10 HDI points (range total score 0 to 70 points) was significantly associated with a decreased risk of all-cause mortality (HR: 0.90 and 95% confidence interval (CI): 0.87-0.93). The HR estimate was equivalent to a two year increase in life expectancy. We found a significant inverse association between an increase of 10 HDI points and CVD mortality for Southern European countries and the US (HR: 0.85, 95 % CI: 0.83-0.87), whereas no significant association was found for Northern and Central and Eastern Europe. An increase of 1 point for the WCRF/AICR diet score (range 0-4) was associated with a significantly 6% decreased risk in developing any type of cancer. Greatest risk reduction was found between a 1 point increase in WCRF/AICR diet score and colorectal cancer (HR: 0.84, 95% CI:0.80-0.89).
Conclusion: Dietary indices based on globally defined dietary recommendations by WHO and WCRF/AICR were found to be associated with all-cause and CVD mortality and cancer risk in old age. Public health interventions targeted on the elderly should not focus on one definition of a “healthy diet” but rather a smart combination of available evidence, to optimally account for CVD as well as cancer specific outcomes.
Nutrition and cognition in older adults : studies on the role of glucose, sucrose, protein, vitamin B12 and folic acid
Zwaluw, N.L. van der - \ 2014
Wageningen University. Promotor(en): Lisette de Groot, co-promotor(en): Ondine van de Rest; Rosalie Dhonukshe-Rutten. - Wageningen : Wageningen University - ISBN 9789462571075 - 184
ouderenvoeding - voeding - ouderen - kenvermogen - glucose - sucrose - eiwittoevoegingen - vitamine b12 - dementie - elderly nutrition - nutrition - elderly - cognition - protein supplements - vitamin b12 - dementia
The age-related cognitive decline and the increase in dementia patients are large problems in societies with growing ageing populations. No cure is present for dementia, while the available medication only focuses on alleviating symptoms. It is therefore of major importance to find risk factors that can modify the development of cognitive decline and dementia. Pre-clinical and observational studies suggest a role for nutrients. Evidence derived from randomized controlled trials (RCTs) is, however, limited and equivocal with most studies showing no effect and only a few studies showing a beneficial effect of a nutritional intervention. In the current thesis, we investigated the acute and longer-term effects of different nutrients, i.e. glucose and sucrose, protein, resistance-type exercise training with or without protein, and vitamin B12 and folic acid in order to optimize and preserve cognitive functions in non-demented elderly people.
A comprehensive literature review was performed on the acute effects of glucose and sucrose on cognitive performance (Chapter 2). Glucose is the most important fuel for the brain, and as such, manipulation of the supply of glucose may affect cognitive functions. The main conclusion of our review was that a glucose load may have a short-term beneficial effect on episodic memory. Enhancing effects on other cognitive domains were less clear, partly due to the small number of studies examining these effects. Limited research was also done on the possible effects of sucrose on cognitive functions. Therefore, we investigated the acute effects of 50 g of glucose and 100 g of sucrose on a broad spectrum of cognitive functions reflecting performance on episodic memory, working memory, attention and information processing speed, and executive functions (Chapter 3). This was done by a cross-over study in 43 elderly participants who had self-reported memory complaints. In contrast to the conclusion of our review, we did not observe an effect of glucose or sucrose on episodic memory, though we showed a beneficial effect of sucrose on attention and information processing speed.
Protein supplementation was the next nutritional intervention that was investigated. Several amino acids are precursors for neurotransmitters, and their supply may affect the synthesis and release of these neurotransmitters, and may consequently affect cognitive performance. A 24-week randomized placebo-controlled trial was carried out in 65 frail and pre-frail elderly people (Chapter 4). The protein supplementation included twice a day 15 grams of protein in the form of a drink. Reaction time improved more in the protein group compared to the placebo group, but the scores on the cognitive domains, i.e. episodic memory, attention and working memory, information processing speed, and executive functions, or the other single test scores, did not differ between treatment groups. In addition, we investigated the effects of 24 weeks resistance-type exercise training with and without protein supplementation in pre-frail and frail elderly people (Chapter 5). Exercise training without extra protein (n=62) improved performance on the domain attention and working memory. Exercise training together with protein supplementation (n=65) improved performance on information processing speed.
Last, the role of vitamin B12 and folate on cognitive health was investigated. Low levels of these nutrients can increase homocysteine levels, which is a suggested risk factor for cognitive decline. The effect of daily supplementation with 500 µg vitamin B12 and 400 µg folic acid was investigated in 2,919 participants for two years (Chapter 6). Global cognitive function and episodic memory were assessed in the total study population, whereas extensive neuropsychological testing was done in a subpopulation (n=856). B-vitamin supplementation did not improve cognitive domain scores. Only a small, though significant, effect was observed on global cognitive performance, measured by the Mini-Mental State Examination, but this was suggested to be due to chance. Brain MRI scans were made in a subgroup (n=218) after two years of intervention to obtain volumetric measures of grey and white matter, and total brain volume (Chapter 7). We investigated the cross-sectional associations between follow-up levels of folate, homocysteine and three vitamin B12 status biomarkers, e.g. methylmalonic acid, holotranscobalamin and serum vitamin B12, and brain volumes. Fully adjusted regression models showed a borderline significant association between plasma homocysteine and total brain volume, with a stronger association in the group that received B-vitamin supplementation. Serum B12 and holotranscobalamin were not associated with brain volumes, whereas high methylmalonic acid levels were associated with lower brain volumes in the group that received B-vitamins. In contrast, higher folate levels were associated with lower total brain volumes. In addition, when comparing the group that received two years of B-vitamin supplementation and those who did not, we observed lower brain volumes in the B-vitamin group, which might be a result of a difference in age between the two groups.
To conclude, the nutritional intervention studies showed little evidence for a beneficial effect on cognitive performance in relatively healthy older adults. Given the large problem of dementia, research on modifiable risk factors, including nutrition, should continue, with well thought out research methods, including large and long-term observational and intervention studies with high-sensitive study populations and early biomarkers (e.g. imaging techniques) for cognitive decline in combination with neuropsychological tests. In this way, nutrition can be added to the list of lifestyle factors that can fight dementia.
Rapportage onderzoeksproject Genieten aan tafel : een toegepast onderzoek naar maaltijdbeleving in verpleeghuizen
Zeinstra, G.G. ; Atten, M.N. van; Ziylan, C. ; Boelsma, E. ; Peppelenbos, H.W. ; Brok, P. den - \ 2014
Wageningen : Wageningen UR - Food & Biobased Research (Rapport / Wageningen UR Food & Biobased Research 1483) - ISBN 9789462570535 - 86
verpleeghuizen - ouderenvoeding - ouderen - perceptie - volksgezondheid - ziektepreventie - maaltijden - nederland - ondervoeding - voedselconsumptie - nursing homes - elderly nutrition - elderly - perception - public health - disease prevention - meals - netherlands - undernutrition - food consumption
Er komen steeds meer ouderen in Nederland. Zij doen over het algemeen een groter beroep op de gezondheidszorg, wat tot stijgende zorgkosten leidt en een lagere kwaliteit van leven. Eten en drinken speelt een belangrijke rol bij de preventie van ziekte. Hoewel er steeds meer aandacht is voor de voedingsstatus van ouderen en screeningsprocedures steeds meer toegepast worden, laten de laatste metingen in Nederland zien dat 17% van de cliënten in instellingen ondervoed is en dat 28% risico loopt op ondervoeding. Om ziekte en daarmee verhoogde zorgkosten te voorkomen, en om de kwaliteit van leven te optimaliseren, is preventie van ondervoeding bij ouderen noodzakelijk. Het onderzoek ‘Genieten aan tafel’ beoogde de maaltijdbeleving van verpleeghuiscliënten te optimaliseren, met als doel om eetlust, voedingsstatus, functionele status en kwaliteit van leven te verbeteren en zo zorgkosten te verminderen.
Voeding en beweging ter preventie van cognitieve achteruitgang
Severs, A. ; Rest, O. van de; Groot, C.P.G.M. de; Loon, L.J.C. van - \ 2014
VoedingsMagazine 27 (2014)1. - ISSN 0922-8012 - p. 18 - 20.
ouderen - ouderenvoeding - eiwittoevoegingen - dementie - kenvermogen - lichaamsbeweging - voeding en gezondheid - voedingsstoffen - elderly - elderly nutrition - protein supplements - dementia - cognition - exercise - nutrition and health - nutrients
Dementie wordt een steeds groter en kostbaarder probleem door de vergrijzing. Wetenschappers zijn naarstig op zoek naar mogelijkheden om het tij te keren. Zo ook dr.ir. Ondine van de Rest, onderzoeker aan Wageningen University. Haar onderzoek is gericht op de rol van voeding bij leeftijdsgerelateerde cognitieve achteruitgang. Samen met prof. dr.Lisette de Groot, hoogleraar voeding voor de oudere mens aan Wageningen Universiteit, en Prof. Dr. Luc van Loon, hoogleraar fysiologie van inspanning aan Maastricht Universiteit, voerde ze binnen het Top Instituut Food and Nutrition (TIFN) een interventiestudie uit bij ouderen naar het effect van eiwitsuppletie en beweging op de cognitie.
Hoe voeden we de oudere mens?
Staveren, W.A. van; Groot, C.P.G.M. de - \ 2014
VoedingsMagazine 27 (2014)1. - ISSN 0922-8012 - p. 21 - 23.
ouderenvoeding - voeding en gezondheid - voedselconsumptie - eetpatronen - voedingsstoffen - ouderen - elderly nutrition - nutrition and health - food consumption - eating patterns - nutrients - elderly
Wat zijn de effecten van voedingspatronen en nutriënten op de gezondheid, het functioneren, en de kwaliteit van leven van ouderen? Het onderzoeksteam van prof. Wija van Staveren en prof. Lisette de Groot in Wageningen heeft de afgelopen kwart eeuw observationele en interventiestudies uitgevoerd om die vragen te beantwoorden. Een symposium in Wageningen inventariseerde wat met dit en ander onderzoek is bereikt op het gebied van voeding voor ouderen.
Vitaal naar de eindstreep
Tieland, C.A.B. ; Rest, O. van de; Groot, C.P.G.M. de - \ 2013
WageningenWorld 2013 (2013)4. - ISSN 2210-7908 - p. 26 - 29.
voeding en gezondheid - ouderen - verouderen - vitaminetekorten - vetzuren - eiwit - gezondheidsbevordering - nutrition and health - elderly - aging - vitamin deficiencies - fatty acids - protein - health promotion
Hoe worden we gezond oud? Trainen en extra eiwitten werken, blijkt uit onderzoek van de afdeling Humane voeding. Over het effect van vitamines en omega-3 vetzuren is het laatste woord nog niet gezegd.
Bones, brains and B-vitamins : the impact of vitamin B12, folate and homocysteine on bone health and cognitive function in elderly
Wijngaarden, J.P. van - \ 2013
Wageningen University. Promotor(en): Lisette de Groot, co-promotor(en): Rosalie Dhonukshe-Rutten. - Wageningen : Wageningen UR - ISBN 9789461737151 - 192
botontkalking - kenvermogen - ouderen - beenderen - vitamine b12 - foliumzuur - homocysteïne - vitaminetoevoegingen - botbreuken - voedingstoestand - osteoporosis - cognition - elderly - bones - vitamin b12 - folic acid - homocysteine - vitamin supplements - bone fractures - nutritional state
An elevated homocysteine level has been indicated as a risk factor for cardiovascular disease, cognitive decline, and fractures. Supplementation of vitamin B12 and folic acid in order to normalize homocysteine levels might be of substantial public health importance as this might reduce the risk for several age-related conditions. This thesis focuses on two health outcomes frequently associated with elevated homocysteine levels and low levels of vitamin B12 and folate: osteoporosis and cognitive decline later in life.
Findings are presented in the context of a model which links dietary intake to biomarkers of nutritional status and subsequently to health outcomes. Two systematic reviews with meta-analyses investigated the current status of knowledge about the association of vitamin B12 intake and status with cognitive function, and the association of homocysteine, vitamin B12 and folate status with bone health. Baseline data of the B-PROOF study were used to assess 1) the association of vitamin B12 intake with status according to four biomarkers (vitamin B12, holotranscobalamin (holoTC), methylmalonic acid (MMA) and homocysteine), 2) the mutual association among these four vitamin B12 biomarkers and 3) the association between homocysteine, vitamin B12 biomarkers, folate and cognitive function. The effect of 2-year daily vitamin B12 (500 μg) and folic acid (400 μg) supplementation on fracture risk was assessed in the B-PROOF study, a large (N=2919) randomized controlled trial in elderly people (aged ≥65 years) with an elevated homocysteine level (≥12.0 µmol/L).
The systematic review of the literature showed no or inconsistent associations of vitamin B12 intake with cognitive function. Furthermore, serum vitamin B12 was not associated with risk of dementia, global cognition or memory. Studies on MMA and holoTC reported significant associations with risk of dementia, Alzheimer’s disease and global cognition. A meta-analysis showed that serum/plasma vitamin B12 per 50 pmol/L was borderline significantly associated with a lower fracture risk (RR=0.96, 95% CI = 0.92-1.00) and that homocysteine was significantly associated with a higher fracture risk (RR=1.04, 95% CI = 1.02-1.07). Meta-analyses regarding vitamin B12, folate and homocysteine levels and BMD did not show significant associations.
In the B-PROOF study a doubling of vitamin B12 intake was associated with 9% higher levels of vitamin B12, 15% higher holoTC, 9% lower MMA and 2% lower homocysteine, saturation of biomarkers occurs with dietary intakes of >5 μg B12. Levels of MMA and homocysteine were higher when vitamin B12 levels were below 330 pmol/L and when holoTC levels were below 100 pmol/L, with a steep elevation when levels of vitamin B12 and HoloTC were below 220 and 50 pmol/L respectively. At baseline, levels of vitamin B12 and holoTC were not associated with cognitive function in any cognitive domain. Levels of homocysteine (β= -0.009), folate (β= 0.002), MMA (β= -0.163) and the wellness score – a vitamin B12 biomarker combination score - (β= 0.048) were significantly associated with the domain of episodic memory. Additionally, homocysteine (β= -0.015) and the wellness score (β= 0.103) were significantly associated with the domain information processing speed.
The B-PROOF intervention did not lower the risk of fracture in the total population (HR=0.84, 95% CI = 0.58-1.22). Per protocol subgroup analysis of elderly aged >80 years, showed a lower risk of fracture in the intervention group (HR=0.28, 95% CI 0.10-0.74). We observed more cancer cases in the intervention group (HR=1.55, 95% CI = 1.04-2.30) compared to the placebo group. We cannot rule out the possibility of accelerated cancer progression as a possible negative side effect.
Our literature reviews and observational data confirm an association of levels of homocysteine, vitamin B12 and folate with cognitive function and fracture risk in elderly. Supplementation with vitamin B12 and folic acid did not lower the risk of fracture in the total study population. Though positive effects on fracture incidence emerged in elderly aged >80 years, these benefits should be weighed against potential risks.
Anthropometrics and ageing : impact of weight status on health
Hollander, E.L. de - \ 2013
Wageningen University. Promotor(en): Lisette de Groot, co-promotor(en): W.J.E. Bemelmans. - S.l. : s.n. - ISBN 9789461736888 - 176
antropometrie - antropometrische dimensies - lichaamsgewicht - verouderen - ouderen - gezondheid - anthropometry - anthropometric dimensions - body weight - aging - elderly - health
Background: Weight status is one of the factors that influence healthy ageing. It is often assessed with anthropometric measures such as body mass index (BMI) and waist circumference (WC), which indicate underweight or excess fat. Both are associated with adverse health outcomes in adults. The first paper of this thesis investigates whether this association is consistent over calendar time, to check for possible influences of improved healthcare procedures over time. In old age, this association is unclear. Using several anthropometric measures, the subsequent five papers examine the impact of weight status and development of weight status on coronary heart disease (CHD), mortality, and quality of life (QoL) among the elderly and during ageing.
Methods: A meta-regression analysis of 31 international cohort studies (n=389,212) was used to estimate the multivariable adjusted relative risk (RR) of CHD for an increased BMI and whether the RR was different between calendar periods (i.e. studies that started before 1985 and studies that started after 1985) taking account of the age of the population. Associations of BMI and changes in eight anthropometric measures with all-cause and cause-specific mortality in old age were studied by means of multivariable Cox regression analyses using data from the Survey in Europe on Nutrition and the Elderly: a concerted action study including 70–77-year-olds (n=1,061–1,970). Moreover, the association of WC with all-cause and cause-specific mortality was studied by means of a meta-analysis of 29 international cohort studies including 65–74-year-olds (n=58,609). For an ageing population, we used the Doetinchem Cohort Study including 20–70-year-olds (n=3,408–4,135) and three to four repeated measures of weight and height over a period of 10 to 15 years. In this study population, we used a multivariable regression analysis to examine the association of changes in weight and long-term BMI patterns with QoL (measured by the SF-36 questionnaire).
Results: After simultaneous inclusion of calendar period and age of the population in the model, the meta-regression analysis showed no difference in the RR of CHD in the association with a high BMI between calendar periods. However, a 10-year increment in population age lowered the 1.28 [95%confidence interval (CI): 1.22–1.34] RR of CHD for a five-BMI-unit increment by 29% (95%CI: -55 to -5). Among the elderly, BMI was associated with all-cause mortality, cardiovascular disease (CVD) mortality, and mortality due to causes other than CVD, cancer, and respiratory diseases (p<0.05). A BMI below 24 kg/m2and above 30 kg/m2were the thresholds at which risks of cause-specific mortality were increased by 10%. WC was associated with all-cause, CVD, cancer, and respiratory disease mortality (p<0.05). At the levels for abdominal obesity (102 cm, men; 88 cm, women), the risk of all-cause and CVD mortality was not significantly increased, or only modestly. A risk of 2.0 (clinically relevant) for all-cause and CVD mortality was associated with a WC of 132 and 123 cm in men, and 116 and 105 cm in women, respectively. By using a combination of WC and BMI categories with the combination of a small WC (94 cm, men; 80 cm, women) and a healthy weight (20.0–24.9 kg/m2) as the reference, we observed the highest all-cause and CVD mortality risk of approximately 2.0 for underweight (<20.0 kg/m2; in combination with a small WC), and abdominal obesity within healthy ranges of BMI. Changes in BMI and WC were not associated with all-cause and CVD mortality, except for a decrease in WC ≥3.1 cm in the association with all-cause mortality (1.52, 95%CI: 1.01–2.31). Similarly, a decrease in weight ≥3.2 kg was associated with a 1.48 (95%CI: 0.99–2.20) increased all-cause mortality risk. Moreover, both a decrease and an increase in mid-upper arm circumference (MUAC) were associated with all-cause mortality and CVD mortality. A decrease of ≥1.6 cm and 0.6–1.6 cm in MUAC was associated with a 1.81 (95%CI: 1.17–2.79) and a 1.66 (95%CI: 1.10–2.49) all-cause mortality risk. An increase of ≥1.3 cm in MUAC was associated with a 1.52 (95%CI: 1.00–2.31) all-cause mortality risk and a 1.94 (95%CI: 1.00–3.75) CVD mortality risk. In an ageing population, we found that weight gain, especially weight gain of >6 kg, resulted in a decline in QoL. Weight loss (>2 kg) did not result in large changes in QoL. However, both weight gain and weight loss were adversely associated with changes in QoL as compared to a stable weight (changes ≤2 kg). From examination of long-term BMI patterns, the lowest QoL was observed for the ‘persistent obesity (≥30 kg/ m2)’ pattern. The BMI patterns, ‘persistent obesity’, ‘developing overweight (25.0–29.9 kg/m2’, ‘developing obesity’, and ‘switching between BMI categories’ scored 1.8–11.6 points (p<0.05) lower on QoL than the ‘persistent healthy weight (18.5–24.9 kg/m2)’ pattern. The BMI pattern ‘persistent overweight’ generally did not differ from the ‘persistent healthy weight’ pattern. These findings were consistent among age groups.
Conclusions: Although the risk of CHD in the association with BMI attenuated with increasing age, we found associations of BMI and WC with all-cause and cause-specific mortality among the elderly. These anthropometric measures can be used as single predictors of mortality for the elderly, but higher cut-off points for BMI and WC to indicate underweight and excess fat should be considered. Moreover, a combination of these two anthropometric measures can be recommended, as that would provide more information of the body composition than one anthropometric alone. With regard to assessing changes in body composition, MUAC might be recommended for the elderly. Furthermore, a stable weight is best for health maintenance among all ages, provided this stable weight does not fall within the extreme values of weight, i.e. too light or too heavy. In all, our results underscore the value of anthropometric measures in the management of weight and the importance of the maintenance of a stable weight during ageing.
Dietary strategies to augment muscle mass in the elderly
Tieland, C.A.B. - \ 2013
Wageningen University. Promotor(en): Lisette de Groot; L.J.C. van Loon. - S.l. : s.n. - ISBN 9789461735676 - 150
eiwittoevoegingen - lichaamsbeweging - spiergewicht - lichamelijke fitheid - ouderen - maatregel op voedingsgebied - protein supplements - exercise - muscle weight - physical fitness - elderly - nutritional intervention
Background: The world population is aging rapidly. This growth of the aging population is accompanied by an increased number of frail elderly people who are at risk of adverse health outcomes such as disability, co-morbidity and mortality. A dominant feature of frailty is the age related loss of muscle mass, strength and performance, also called sarcopenia. Resistance-type exercise training and dietary protein supplementation are considered promising strategies to reverse sarcopenia and subsequent frailty. However, strong evidence for the impact of protein supplementation with or without resistance exercise in frail elderly people is scarce. Well-designed intervention studies in frail elderly people are needed to define new leads for the development of nutritional and exercise interventions to effectively prevent or treat the progressive loss of muscle mass, strength and physical performance with aging. Therefore, the aims of this thesis are to study 1) the impact of protein supplementation and 2) the impact of protein supplementation during prolonged resistance-type exercise training on muscle mass, strength and physical performance in frail elderly people.
Methods: First, we studied various characteristics of dietary protein intake, including the distribution of dietary protein intake throughout the day, and the use of protein-containing food sources in various elderly populations. With this knowledge, we designed two large intervention trials to study the impact of dietary protein supplementation with or without prolonged resistance-type exercise training on muscle mass, strength and physical performance in frail elderly people. In addition, we assessed the usefulness of handgrip strength as a measure of post exercise strength differences and studied the association of vitamin D status and vitamin D intake on muscle mass, strength and physical performance in a frail elderly population.
Results: Dietary protein intake in frail and institutionalized elderly people were especially low at breakfast and lunch. Supplementing protein at breakfast and lunch did not increase muscle mass but improved physical performance in frail elderly people. Resistance-type exercise training improved muscle leg strength and physical performance, but not handgrip strength. Supplementing protein at breakfast and lunch was required to significantly increase muscle mass during prolonged resistance-type exercise training in frail elderly people. Furthermore, low vitamin D status and vitamin D intake were associated with impaired physical performance.
Conclusions: Although dietary protein supplementation does not increase muscle mass, it represents a promising strategy to improve physical performance in frail elderly people. Prolonged resistance-type exercise training represents an effective strategy to improve strength and physical performance, but dietary protein supplementation is required to allow muscle mass gain during exercise training in frail elderly people.