Vitamin D for older adults : Determinants of status, supplementation strategies and its role in muscle function
Vaes, Anouk M.M. - \ 2017
Wageningen University. Promotor(en): C.P.G.M. de Groot, co-promotor(en): M. Tieland. - Wageningen : Wageningen University - ISBN 9789463436144 - 164
vitamin d - deficiency - aging - vitamin supplements - dosage effects - musculoskeletal system - literature reviews - food enrichment - skeletal muscle - food supplements - randomized controlled trials - vitamine d - deficiëntie - verouderen - vitaminetoevoegingen - doseringseffecten - skeletspierstelsel - literatuuroverzichten - voedselverrijking - skeletspier - voedselsupplementen - gestuurd experiment met verloting
Vitamin D has been identified as an important factor in healthy aging and is receiving growing attention in clinical research. Vitamin D is a fat-soluble molecule, which is synthesized by hepatic and renal or extra-renal hydroxylation into the active hormone 1,25-dihydroxyvitamin D (1,25(OH)2D). The main function of this metabolite is to regulate calcium and phosphorus homeostasis and to support bone mineralization. In the circulation, the 25-hydroxyvitamin D metabolite (25(OH)D) is most stable and thus, considered the best marker of vitamin D status. A serum 25(OH)D concentration <30-50 nmol/L is considered deficient. Given the increased risk of deficiency and the potential beneficial effect of supplementation on musculoskeletal health, older adults present a specific target group for vitamin D interventions. However, the optimal serum 25(OH)D concentration is a matter of ongoing debate as randomized trials show conflicting results.
With the research presented in this thesis, we aimed to gain insight in the prevalence and main determinants of a low vitamin D status, to investigate strategies to prevent or reverse vitamin D deficiency, and to study the effect of vitamin D supplementation on muscle strength and physical performance in Dutch older adults.
In chapter 2, we examined the prevalence and the main determinants of a low vitamin D status in a large population of community-dwelling older adults (n=2857). Vitamin D deficiency was highly prevalent, with serum 25(OH)D concentrations <50 nmol/L in 45%, and <30 nmol/L in 14% of the population. When exploring the main determinants of serum 25(OH)D status, significant associations were observed with age, BMI, dietary intake, sun exposure behavior, and genetic polymorphisms encoding for enzymes in the vitamin D pathway. Combined, these factors explained 35% of the variation in serum 25(OH)D concentrations.
To explore potential strategies that prevent vitamin D deficiency, we investigated the contribution of dietary vitamin D intake and specific food groups to serum 25(OH)D concentration in chapter 3. Daily vitamin D intake from dietary sources showed a median (25-75th percentile) intake of 4.0 (3.0-5.4) µg/day (n=595) and only 12-20% of older adults reported to take vitamin D supplements. These findings are in sharp contrast with the current nutrient guidelines and show that the vast majority of older adults do not meet the reference intakes for vitamin D. Nevertheless, significant associations were observed between the highest tertile of dietary vitamin D intake and serum 25(OH)D concentration, suggesting that regular intake of foods rich in vitamin D can support the prevention of modest insufficiency.
For the majority of older adults, supplementation is required to ensure sufficient serum 25(OH)D concentrations throughout the year. Currently, supplementation with vitamin D3 is the most common strategy. However, alternative treatment regimens exist that require further investigation. In chapter 4, we report on a dose-response trial (n=59) that investigated the efficacy of calcifediol (5, 10 or 15 µg/d) as a supplementation strategy. Compared to vitamin D3, calcifediol is more hydrophilic, does not require hepatic hydroxylation, and binds with higher affinity to its binding proteins. In our study, we observed that calcifediol was safe and well tolerated in the supplemented doses over the entire study period of 6-months. We concluded that a dose of 10 µg/day resulted in sustained serum 25(OH)D concentrations between 75-100 nmol/L. Furthermore, calcifediol had a ~3 times higher potency when compared to vitamin D3, in increasing serum 25(OH)D concentrations. All in all, calcifediol may offer a valuable supplementation regimen to rapidly correct deficiency.
Vitamin D presents an important endocrine regulator in the musculoskeletal health of older adults. Besides its role in bone health, low serum 25(OH)D concentrations have been linked to impaired physical performance and increased risk of falling. The active metabolite 1,25-dihydroxyvitamin D is suggested to act upon a wide variety of cells throughout the body, including muscle cells. Although the exact mechanisms by which vitamin D acts on muscle are unclear, several indirect or direct regulatory pathways have been described, including effects of 1,25-dihyroxyvitamin D through intracellular calcium and phosphate homeostasis, or via activation of transcription factors when binding to the vitamin D receptor in muscle cells.
In chapter 5 we observed significant associations between low serum 25(OH)D concentrations, physical performance and frailty in community-dwelling older adults (n=494-756). However, randomized trials are needed to define the causality of the observed associations. A previous pilot study indicated plausible beneficial effects of calcifediol over vitamin D3 on performance and strength. As such, we aimed to further explore the potential role of calcifediol or vitamin D3 on muscle function in chapter 6. We performed a placebo-controlled trial in pre-frail and frail, vitamin D deficient older adults, supplementing either 10 µg/d calcifediol or 20 µg/d vitamin D3, compared to placebo over a 6-month period (n=78). Again, calcifediol induced a faster and higher increase in serum 25(OH)D status when compared to vitamin D3. However, we observed no effect of either supplementation regimen on lower extremity strength or physical performance. Current literature suggests positive effects on strength and balance when supplementing with vitamin D, however, results are inconsistent. Meta-analyses of randomized trials indicate that the beneficial effects of vitamin D supplementation might be more pronounced in vulnerable populations with more severe vitamin D deficiencies.
All in all, the high prevalence of vitamin D deficiency is alarming. Promoting adequate vitamin D status is important considering the beneficial effects on bone health. In the last decade, research has come a long way in exploring the role of vitamin D in muscle function. However, the evidence base remains uncertain and further research on the optimal vitamin D status for older adults is needed to guide clinical practice. Until then, focus should be placed on prevention and identification of deficiency.
Understanding heterogeneity in decision-making among elderly consumers: the case of functional foods
Zanden, Lotte D.T. van der - \ 2017
Wageningen University. Promotor(en): J.C.M. van Trijp, co-promotor(en): P.W. Kleef; R.A. 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 - marketing - 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.
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.
Dry fractionation for sustainable production of plant protein concentrates
Pelgrom, P.J.M. - \ 2015
Wageningen University. Promotor(en): Remko Boom, co-promotor(en): Maarten Schutyser. - Wageningen : Wageningen University - ISBN 9789462572355 - 202
fractionering - peulvruchten (groente) - mechanische eigenschappen - eiwitextractie - voedselverrijking - fractionation - vegetable legumes - mechanical properties - protein extraction - food enrichment
The global demand for protein-rich foods is expected to double in the coming decades due to the increasing prosperity and world population. To keep up with the demand, the transition from an animal to a plant-based protein supply is desirable from long-term economic and environmental perspectives. In particular, legumes such as pea and lupine are of interest due to their nutritional profile and high protein content. Legume proteins are commonly purified by wet fractionation, which consumes large amount of water and energy and alters the native functionality of the proteins. Therefore, this thesis describes a sustainable, dry fractionation method for legumes to obtain functional protein-enriched fractions. Firstly, experiments have been performed to increase understanding of both the material properties of legume seeds and of the process conditions relevant to dry fractionation. Dedicated milling settings were selected for starch-rich and oil-rich legumes based on legume morphology. Milling settings were estimated based on starch granule size in starch-rich legumes, while coarse milling provided better results for oil-rich legumes. Separation of the protein bodies from other cellular components was established by air classification, which consumed ten times less energy and 50 litre water per kg protein less compared to conventional wet fractionation. Secondly, the functionality of the fractions was analysed. The dry-enriched protein fractions provided higher solubility than conventionally produced fractions, making them suitable for high protein drinks. Moreover, pea fractions could also be gelatinized which opens opportunities for preparing solid protein foods such as meat replacers. In conclusion, this thesis contributes to the awareness that the food industry could exploit a more sustainable dry fractionation technique to obtain functional protein fractions rather than focussing on wet extraction of relative pure protein ingredients.
Pasta highly enriched with vegetables: from microstructure to sensory and nutritional aspects
Vicente Da Silva, E.M. - \ 2013
Wageningen University. Promotor(en): Erik van der Linden, co-promotor(en): Leonard Sagis; Elke Scholten; Matthijs Dekker. - S.l. : s.n. - ISBN 9789461736864 - 167
deegwaren - broccoli - voedselverrijking - reologische eigenschappen - sensorische evaluatie - voedingswaarde - pasta - broccoli - food enrichment - rheological properties - sensory evaluation - nutritive value
A lifestyle that combines poor food choices with very low or no physical activity can result in the development of diseases such as obesity, and this is affecting a growing number of children. One of the most effective strategies to fight obesity combines physical activity and the consumption of low energy-dense foods, such as vegetables. Vegetables are known to have health benefits but are often non-appealing to children/adolescents due to their bitterness, undesired texture, and their low satiating capacity. One of the possible solutions to increase vegetable intake by children is to incorporate vegetables in a food matrix they like. Several studies have shown that pasta is very much appreciated by children, making it an ideal candidate for the development of vegetable-enriched foods. In this work, dried broccoli powder (BP) was used to enrich pasta-like products. We have investigated aspects that are important to sensorial properties and aspects related to possible health benefits. One aspect relevant to sensorial properties is rheology. The rheology of sweet potato starch (SPS) dough was drastically affected by high volume fractions of BP. This was caused by the swelling of the broccoli powder, up to a maximum of 7.6 times their original volume. In order to control this high swelling capacity of the particles two approaches were followed and both resulted in the prevention of particle swelling. The first was the use of hydrocolloids with high water binding capacity (e.g. xanthan gum) and the second was the use of a different matrix (durum wheat semolina (DWS)). DWS pasta did not show to be greatly affected by the incorporation of high amounts of broccoli powder. The acceptability of pasta products was assessed using a test panel. The results showed that all samples tested (0 – 30%BP) were acceptable, where 30% BP turned out to be on the limit of acceptability. Glucosinolates (GLs) are phytochemicals that are associated with the health benefits of broccoli. An increasing volume fraction of broccoli powder resulted in an increasing content of glucosinolates in dried cooked pasta. At volume fractions higher than 20% BP this effect levels off. From this work, we can conclude that as much as 20% BP can be added to DWS pasta to improve nutritional properties (in terms of GLs) while maintaining acceptable sensorial properties.
Gezonde vis alternatieven literatuurstudie binnen het beleidsondersteunende project "Nieuwe marktgerichte duurzame eiwitconcepten"
Sluis, A.A. van der; Vereijken, J.M. - \ 2013
Wageningen : Wageningen UR - Food & Biobased Research (Rapport / Wageningen UR Food & Biobased Research nr 1383) - 39
vis - visconsumptie - docosahexaeenzuur - eicosapentaeenzuur - omega-3 vetzuren - voedingsstoffenbronnen - algen - aanbevolen dagelijkse hoeveelheden - voedingsmiddelenwetgeving - voedselverrijking - voeding en gezondheid - Nederland - fish - fish consumption - docosahexaenoic acid - eicosapentaenoic acid - omega-3 fatty acids - nutrient sources - algae - recommended dietary allowances - food legislation - food enrichment - nutrition and health - Netherlands
Within the policy supporting project "New market-oriented sustainable protein concepts" (BO-08-018.03-002), a literature study is performed to healthy fish alternatives. The research question was: "What is the nutritional importance of fish consumption, what are alternatives to fish, are there technological and legal barriers, and what are the limits for enrichment with nutritional components?"
Onzekere effecten van foliumzuur op andere aandoeningen dan neuraalbuisdefecten
Verhoef, P. ; Katan, M.B. - \ 2006
Nederlands Tijdschrift voor Geneeskunde 150 (2006)26. - ISSN 0028-2162 - p. 1439 - 1442.
foliumzuur - foliumzuurtekort - voedseladditieven - voedselverrijking - ziektepreventie - gezondheid - vitamine b complex - folic acid - folic acid deficiency - food additives - food enrichment - disease prevention - health - vitamin b complex
Periconceptional supplemention with folic acid prevents neural-tube defects in infants. However, contrary to expectations, clinical trials found no beneficial effect of folic acid on the recurrence of cardiovascular disease. Trial evidence on folic acid and cognitive decline or dementia is scarce, though observational studies suggest that high folate intake may prevent these disorders. In contrast, animal studies suggest that high doses of folic acid enhance the growth of existing tumours. However, recent clinical trials failed to show significant effects of folic acid on cancer incidence and mortality
Foliumzuurverrijking: zowel preventie als bevordering van kanker
Kloosterman, J. ; Jong, N. ; Rompelberg, C.J.M. ; Kampman, E. ; Ocké, M.C. - \ 2006
Nederlands Tijdschrift voor Geneeskunde 150 (2006)126. - ISSN 0028-2162 - p. 1443 - 1448.
foliumzuur - vitamine b complex - foliumzuurtekort - gezondheid - voedseladditieven - voedselverrijking - ziektepreventie - folic acid - vitamin b complex - folic acid deficiency - health - food additives - food enrichment - disease prevention
In many countries foods are fortified with folic acid to prevent neuraltube defects. Beneficial effects on cancer, cardiovascular diseases and dementia are also assumed. As well as beneficial effects, harmful effects may also occur. In addition to masking vitamin-B12 deficiency, there is some evidence that folic acid may promote progression of established tumours in laboratory animals and humans. In addition, it has been hypothesized that fortification with folic acid may have further negative effects on cancer through genetic selection. Given the high prevalence of cancer, these potentially harmful effects should also be taken into account in the Dutch debate on the advantages and disadvantages of folic acid fortification
Halvarine met plantensterolen van de verzekering [Cost of foods fortified with plant sterols refunded by a health insurance company]
Katan, M.B. - \ 2005
Nederlands Tijdschrift voor Geneeskunde 149 (2005)7. - ISSN 0028-2162 - p. 330 - 332.
margarine - sterolen - voedselsamenstelling - gezondheidsbevordering - cholesterolverlagende middelen - voedselverrijking - volksgezondheid - ziektepreventie - ziektekostenverzekering - foliumzuur - margarine - sterols - food composition - health promotion - anticholesteremic agents - food enrichment - public health - disease prevention - health insurance - folic acid
The Dutch health insurance company VGZ recently decided to refund part of the cost of using spread, yogurt and milk fortified with plant sterols. Plant sterols lower plasma cholesterol concentrations but they do so less effectively than statins. For health insurance companies wishing to improve the health of their clients, it would be more logical to reimburse costs of folic acid supplements for the prevention of neural tube defects, and vitamin-D-enriched products to prevent fractures in elderly people