Staff Publications

Staff Publications

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    'Staff publications' is the digital repository of Wageningen University & Research

    'Staff publications' contains references to publications authored by Wageningen University staff from 1976 onward.

    Publications authored by the staff of the Research Institutes are available from 1995 onwards.

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Food matrix effects on bioaccessibility of B-Carotene can be measured in a vitro gastrointestinal model
Loo-Bouwman, C.A. van; Naber, T.H.J. ; Minekus, M. ; Hulshof, P.J.M. ; Schaafsma, G. - \ 2014
Journal of Agricultural and Food Chemistry 62 (2014)4. - ISSN 0021-8561 - p. 950 - 955.
green leafy vegetables - digestion method - pro-vitamin - folic-acid - accessibility - serum - bioavailability - absorption - retinol - cassava
Since the food matrix determines ß-carotene availability for intestinal absorption, food matrix effects on the bioaccessibility of ß-carotene from two diets were investigated in vitro and compared with in vivo data. The “mixed diet” consisted of ß-carotene-rich vegetables, and the “oil diet” contained ß-carotene-low vegetables with supplemental ß-carotene. The application of extrinsically labeled ß-carotene was also investigated. The bioaccessibility of ß-carotene was 28 µg/100 µg ß-carotene from the mixed diet and 53 µg/100 µg ß-carotene from the oil diet. This ratio of 1.9:1 was consistent with in vivo data, where the apparent absorption was 1.9-fold higher in the oil diet than in the mixed diet. The labeled ß-carotene was not equally distributed over time. In conclusion, the food matrix effects on bioaccessibility of ß-carotene could be measured using an in vitro model and were consistent with in vivo data. The application of extrinsically labeled ß-carotene was not confirmed.
Associations between medication use and homocysteine levels in an older population, and potential mediation by vitamin B12 and folate: data from the B-PROOF study
Ham, A.C. ; Enneman, A.W. ; Dijk, S.C. van; Wijngaarden, J.P. van; Zwaluw, N.L. van der; Brouwer, E.M. ; Dhonukshe-Rutten, R.A.M. ; Groot, C.P.G.M. de; Witkamp, R.F. - \ 2014
Drugs & Aging 31 (2014)8. - ISSN 1170-229X - p. 611 - 621.
type-2 diabetes-mellitus - plasma homocysteine - folic-acid - cardiovascular risk - parkinsons-disease - essential-hypertension - serum concentrations - c677t polymorphism - pharmacy records - controlled-trial
Background Elevated homocysteine levels are a risk indicator for cardiovascular disease, fractures and cognitive decline. Previous studies indicated associations between homocysteine levels and medication use, including antihypertensive, lipid-lowering and antidiabetic medication. However, results were often contradictory and inconclusive. Our objective was to study the associations established previously in more detail by sub-classifying medication groups, and investigate the potential mediating role of vitamin B12 and folate status. Materials and Methods Baseline data from the B-PROOF (B-vitamins for the PRevention Of Osteoporotic Fractures) study were used. We included 2,912 participants aged =65 years, with homocysteine levels of 12–50 µmol/L and creatinine levels =150 µmol/L, for whom self-reported medication data were available. We used multivariable linear regression models and analysis of covariance to assess the association between medication use and plasma homocysteine levels, and the potential mediation by serum vitamin B12 and folate. Results The mean age was 74 years (standard deviation, 6.5), 50 % were women, and median homocysteine levels were 14 µmol/L [interquartile range, 13–17 µmol/L]. Higher mean homocysteine levels were observed in users vs. non-users for diuretics (15.2 vs. 14.9, p = 0.043), high-ceiling sulphonamide diuretics (16.0 vs. 14.9, p <0.001), medication acting via the renin-angiotensin system (15.2 vs. 14.9, p = 0.029) and metformin (15.6 vs. 15.1, p = 0.006). Non-selective ß-blocker use was associated with lower mean homocysteine levels (14.4 vs. 15.0, p = 0.019). Only this association was mediated by an underlying association with vitamin B12 and folate levels. Conclusion The associations between homocysteine levels and medication use appear to be fairly modest. Our results suggest that medication use is unlikely to contribute to clinically relevant changes in plasma homocysteine levels.
Effect of soybean processing on content and bioaccessibility of folate, vitamin B12 and isoflavones in tofu and tempe
Mo, H. ; Kariluoto, S. ; Piironen, V. ; Zhu, Y. ; Sanders, M.G. ; Vincken, J.P. ; Wolkers-Rooijackers, J.C.M. ; Nout, M.J.R. - \ 2013
Food Chemistry 141 (2013)3. - ISSN 0308-8146 - p. 2418 - 2425.
solid-substrate fermentation - folic-acid - in-vitro - gastrointestinal model - nutritional value - binding protein - bioavailability - rats - calcium - women
Purpose - To compare the content of bioaccessible folate, vitamin B12, and isoflavones in tofu and tempe, as influenced by soybean variety and food processing, particularly fermentation. Principal results - Raw soybeans contained 2207–2671 µg/kg (dry matter) folate, cooked tempe 1493–4143, and cooked tofu 968–1273 µg/kg, the difference was attributed to the fermentation in tempe. Vitamin B12 was detected only in tempe (0.16–0.72 µg/kg). Isoflavone aglycones were formed during soaking of soybeans, with only minor differences between the contents in cooked tempe (average 1922–2968 µg/kg) or tofu (1667–2782 µg/kg) but strongly depending on bean variety. Conclusions - Folate and vitamin B12 contents were mainly influenced by microbial activity during fermentation, whereas isoflavone aglycone content was determined by bean variety. Tofu had lower folate and vitamin B12, but equal isoflavone contents as tempe. Bioaccessibility of folate (80–100%) and isoflavone aglycones (100%) were high
Enhancing pterin and para-aminobenzoate content is not sufficient to successfully biofortify potato tubers and Arabidopsis thaliana plants with folate
Blancquaert, D. ; Storozhenko, S. ; Daele, W. ; Stove, C. ; Visser, R.G.F. ; Lambert, W. ; Straeten, D. van der - \ 2013
Journal of Experimental Botany 64 (2013)12. - ISSN 0022-0957 - p. 3899 - 3909.
time quantitative pcr - folic-acid - tomato fruit - gene - expression - transformation - homocysteine - promoter - disease - fortification
Folates are important cofactors in one-carbon metabolism in all living organisms. Since only plants and micro- organisms are capable of biosynthesizing folates, humans depend entirely on their diet as a folate source. Given the low folate content of several staple crop products, folate deficiency affects regions all over the world. Folate biofortification of staple crops through enhancement of pterin and para-aminobenzoate levels, precursors of the folate biosynthesis pathway, was reported to be successful in tomato and rice. This study shows that the same strategy is not sufficient to enhance folate content in potato tubers and Arabidopsis thaliana plants and concludes that other steps in folate biosynthesis and/or metabolism need to be engineered to result in substantial folate accumulation. The findings provide a plausible explanation why, more than half a decade after the proof of concept in rice and tomato, successful folate biofortification of other food crops through enhancement of para-aminobenzoate and pterin content has not been reported thus far. A better understanding of the folate pathway is required in order to determine an engineering strategy that can be generalized to most staple crops.
Plasma B vitamins and LINE-1 DNA methylation in leukocytes of patients with a history of colorectal adenomas
Jung, A.Y. ; Botma, A. ; Lute, C. ; Blom, H.J. ; Ueland, P.M. ; Kvalheim, G. ; Midttun, O. ; Nagengast, F. ; Steegenga, W.T. ; Kampman, E. - \ 2013
Molecular Nutrition & Food Research 57 (2013)4. - ISSN 1613-4125 - p. 698 - 708.
one-carbon metabolism - human methylenetetrahydrofolate reductase - moderate folate-depletion - tandem mass-spectrometry - microbiological assay - liquid-chromatography - common mutation - colon-cancer - risk-factor - folic-acid
Scope Low concentrations of folate, other B vitamins, and methionine are associated with colorectal cancer risk, possibly by changing DNA methylation patterns. Here, we examine whether plasma concentrations of B vitamins and methionine are associated with methylation of long interspersed nuclear element-1 (LINE-1) among those at high risk of colorectal cancer, i.e. patients with at least one histologically confirmed colorectal adenoma (CRA) in their life. Methods and results We used LINE-1 bisulfite pyrosequencing to measure global DNA methylation levels in leukocytes of 281 CRA patients. Multivariable linear regression was used to assess associations between plasma B vitamin concentrations and LINE-1 methylation levels. Plasma folate was inversely associated with LINE-1 methylation in CRA patients, while plasma methionine was positively associated with LINE-1 methylation. Conclusion This study does not provide evidence that in CRA patients, plasma folate concentrations are positively related to LINE-1 methylation in leukocytes but does suggest a direct association between plasma methionine and LINE-1 methylation in leukocytes.
Systematic review with dose-response meta-analyses between vitamin B-12 intake and European Micronutrient Recommendations Aligned’s prioritized biomarkers of vitamin B-12 including randomized controlled trials and observational studies in adults and elderly persons
Dullemeijer, C. ; Souverein, O.W. ; Doets, E.L. ; Voet, H. van der; Wijngaarden, J.P. van; Boer, W.J. de; Plada, M. ; Dhonukshe-Rutten, R.A.M. ; Veld, P.H. in 't; Cavelaars, A.J.E.M. ; Groot, C.P.G.M. de; Veer, P. van 't - \ 2013
American Journal of Clinical Nutrition 97 (2013)2. - ISSN 0002-9165 - p. 390 - 402.
b-vitamins - folic-acid - homocysteine concentration - nutritional-status - multivitamin supplementation - methylmalonic acid - oral vitamin-b-12 - older-adults - plasma homocysteine - cognitive function
Background: Many randomized controlled trials (RCTs) and observational studies have provided information on the association between vitamin B-12 intake and biomarkers. The use of these data to estimate dose-response relations provides a useful means to summarize the body of evidence. Objective: We systematically reviewed studies that investigated vitamin B-12 intake and biomarkers of vitamin B-12 status and estimated dose-response relations with the use of a meta-analysis. Design: This systematic review included all RCTs, prospective cohort studies, nested case-control studies, and cross-sectional studies in healthy adult populations published through January 2010 that supplied or measured dietary vitamin B-12 intake and measured vitamin B-12 status as serum or plasma vitamin B-12, methylmalonic acid (MMA), or holotranscobalamin. We calculated an intake-status regression coefficient () for each individual study and calculated the overall pooled and SE () by using random-effects meta-analysis on a double-log scale. Results: The meta-analysis of observational studies showed a weaker slope of dose-response relations than the meta-analysis of RCTs. The pooled dose-response relation of all studies between vitamin B-12 intake and status indicated that a doubling of the vitamin B-12 intake increased vitamin B-12 concentrations by 11% (95% CI: 9.4%, 12.5%). This increase was larger for studies in elderly persons (13%) than in studies in adults (8%). The dose-response relation between vitamin B-12 intake and MMA concentrations indicated a decrease in MMA of 7% (95% CI: -10%, -4%) for every doubling of the vitamin B-12 intake. The assessment of risk of bias within individual studies and across studies indicated risk that was unlikely to seriously alter these results. Conclusion: The obtained dose-response estimate between vitamin B-12 intake and status provides complementary evidence to underpin recommendations for a vitamin B-12 intake of populations.
Vitamin B12 intake and status and cognitive function in elderly people
Doets, E.L. ; Wijngaarden, J.P. van; Szczecinska, A. ; Dullemeijer, C. ; Souverein, O.W. ; Dhonukshe-Rutten, R.A.M. ; Cavelaars, A.J.E.M. ; Veer, P. van 't; Brzozowska, A.M. ; Groot, C.P.G.M. de - \ 2013
Epidemiologic Reviews 35 (2013)1. - ISSN 0193-936X - p. 2 - 21.
randomized controlled-trial - incident alzheimers-disease - placebo-controlled trial - task-force consensus - folic-acid - methylmalonic acid - older-people - serum vitamin-b-12 - dietary-folate - holo-transcobalamin
Current recommendations on vitamin B12 intake vary from 1.4 to 3.0 µg per day and are based on the amount needed for maintenance of hematologic status or on the amount needed to compensate obligatory losses. This systematic review evaluates whether the relation between vitamin B12 intake and cognitive function should be considered for underpinning vitamin B12 recommendations in the future. The authors summarized dose-response evidence from randomized controlled trials and prospective cohort studies on the relation of vitamin B12 intake and status with cognitive function in adults and elderly people. Two randomized controlled trials and 6 cohort studies showed no association or inconsistent associations between vitamin B12 intake and cognitive function. Random-effects meta-analysis showed that serum/plasma vitamin B12 (50 pmol/L) was not associated with risk of dementia (4 cohort studies), global cognition z scores (4 cohort studies), or memory z scores (4 cohort studies). Although dose-response evidence on sensitive markers of vitamin B12 status (methylmalonic acid and holotranscobalamin) was scarce, 4 of 5 cohort studies reported significant associations with risk of dementia, Alzheimer's disease, or global cognition. Current evidence on the relation between vitamin B12 intake or status and cognitive function is not sufficient for consideration in the development of vitamin B12 recommendations. Further studies should consider the selection of sensitive markers of vitamin B12 status.
Dietary intake and biological measurement of folate: A qualitative review of validation studies
Park, Y.H. ; Vollset, S.E. ; Boonstra, A. ; Chajes, V. ; Ueland, P.M. ; Slimani, N. - \ 2013
Molecular Nutrition & Food Research 57 (2013)4. - ISSN 1613-4125 - p. 562 - 581.
food-frequency questionnaire - neural-tube defects - plasma homocysteine concentrations - whole-blood folate - folic-acid - micronutrient intake - additional measurements - degradation-products - biochemical markers - statistical-methods
Folate is a nutrient of major health significance, but its dietary intake assessment is particularly complex to quantify through traditional approaches. Attempts have been made to validate dietary instruments for assessing folate intake against circulating concentration biomarkers. However, this requires careful attention on various methodological issues. We conducted a qualitative review of 17 recently published validation studies to identify these issues. The majority of the tested instruments were self-administered food frequency questionnaires while the biomarker most frequently used was serum/plasma folate. Seasonality was not considered in most studies. Little attention was given to using updated food composition databases based on reliable chemical methods and including fortified foods and dietary supplements. Time sequence of the test instrument and the reference biomarker used was often ambiguous, and reference periods did not always match. Correlation coefficient was the metric most commonly used, and correlations between dietary folate intake and blood folate concentration varied from weak to moderate (r = 0.05–0.54). The correlations were stronger when dietary supplement use was considered, and when serum/plasma rather than red blood cell folate was used. This review summarises issues that need to be considered in future studies intending to validate instruments for dietary folate assessment against concentration biomarkers.
Association between vitamin B12 intake and EURRECA’s prioritized biomarkers of vitamin B12 in young populations: a systematic review
Iglesia, I. ; Dhonukshe-Rutten, R.A.M. ; Bel-Serrat, S. ; Doets, E.L. ; Cavelaars, A.J.E.M. ; Veer, P. van 't; Nissenshohn, M. ; Benetou, V. ; Hermoso, M. ; Berti, C. ; Groot, C.P.G.M. de; Moreno, L.A. - \ 2013
Public Health Nutrition 16 (2013)10. - ISSN 1368-9800 - p. 1843 - 1860.
neural-tube defects - plasma homocysteine concentrations - nutrient intake values - maternal serum folate - birth-weight infants - early-pregnancy loss - folic-acid - micronutrient status - cobalamin status - school-children
Objective To review evidence on the associations between vitamin B12 intake and its biomarkers, vitamin B12 intake and its functional health outcomes, and vitamin B12 biomarkers and functional health outcomes. Design A systematic review was conducted by searching electronic databases, until January 2012, using a standardized strategy developed in the EURRECA network. Relevant articles were screened and sorted based on title and abstract, then based on full text, and finally included if they met inclusion criteria. A total of sixteen articles were included in the review. Setting Articles covered four continents: America (n 4), Europe (n 8), Africa (n 1) and Asia (n 3). Subjects Population groups included healthy infants, children and adolescents, and pregnant and lactating women. Results From the total number of 5815 papers retrieved from the initial search, only sixteen were eligible according to the inclusion criteria: five for infants, five for children and adolescents, and six for pregnant and lactating women. Conclusions Only one main conclusion could be extracted from this scarce number of references: a positive association between vitamin B12 intake and serum vitamin B12 in the infant group. Other associations were not reported in the eligible papers or the results were not provided in a consistent manner. The low number of papers that could be included in our systematic review is probably due to the attention that is currently given to research on vitamin B12 in elderly people. Our observations in the current systematic review justify the idea of performing well-designed studies on vitamin B12 in young populations.
Dietary supplement use is not associated with recurrence of colorectal adenomas : a prospective cohort study
Heine-Bröring, R.C. ; Winkels, R.M. ; Botma, A. ; Wahab, P.J. ; Tan, A.C.I.T.L. ; Nagengast, F.M. ; Witteman, B.J.M. ; Kampman, E. - \ 2013
International Journal of Cancer 132 (2013)3. - ISSN 0020-7136 - p. 666 - 675.
food frequency questionnaire - health interview survey - vitamin-d - united-states - life-style - folic-acid - antioxidant vitamins - relative validity - clinical-trial - cancer risk
Diet and lifestyle influence colorectal adenoma recurrence. The role of dietary supplement use in colorectal adenoma recurrence remains controversial. In this prospective cohort study, we examined the association between dietary supplement use, total colorectal adenoma recurrence and advanced adenoma recurrence. Colorectal adenoma cases (n = 565) from a former case–control study, recruited between 1995 and 2002, were prospectively followed until 2008. Adenomas with a diameter of =1 cm and/or (tubulo)villous histology and/or with high grade dysplasia and/or =3 adenomas detected at the same colonic examination were considered advanced adenomas. Hazard ratios (HRs) and 95% confidence intervals (CIs) for dietary supplement users (use of any supplement during the past year) compared to nonusers and colorectal adenoma recurrence were calculated using stratified Cox proportional hazard models for counting processes and were adjusted for age, sex, educational level and number of colonoscopies during follow-up. Robust sandwich covariance estimation was used to adjust for the within subject correlation. A number of 165 out of 565 adenoma patients had at least one colorectal adenoma recurrence during a median person-time of 5.4 years and of these, 37 patients had at least one advanced adenoma. One-third of the total study population (n = 203) used a dietary supplement. Compared to no use, dietary supplement use was neither statistically significantly associated with total colorectal adenoma recurrence (HR = 1.03; 95% CI 0.79–1.34) nor with recurrent advanced adenomas (HR = 1.59; 95% CI 0.88–2.87). This prospective cohort study did not suggest an association between dietary supplement use and colorectal adenoma recurrence
Homocysteine, progression of ventricular enlargement, and cognitive decline. The Second Manifestations of ARTerial disease-Magnetic Resonance Study
Jochemsen, H.M. ; Kloppenborg, R.P. ; Groot, C.P.G.M. de; Kampman, E. ; Mali, W.P. ; Graaf, C. de; Geerlings, M.I. - \ 2013
Alzheimer's & Dementia 9 (2013)3. - ISSN 1552-5260 - p. 302 - 309.
brain atrophy - plasma homocysteine - risk-factor - folic-acid - probabilistic segmentation - elderly individuals - smart-mr - dementia - impairment - lesions
Background Homocysteine may be a modifiable risk factor for cognitive decline and brain atrophy, particularly in older persons. We examined whether homocysteine increased the risk for cognitive decline and brain atrophy, and evaluated the modifying effect of age. Methods Within the Second Manifestations of ARTerial disease-Magnetic Resonance study—a prospective cohort study among patients with atherosclerotic disease—longitudinal analyses were performed in 663 patients (mean age: 57 ± 9 years; follow-up: 3.9 ± 0.4 years). At baseline and follow-up, brain segmentation on magnetic resonance imaging was used to quantify relative (%) cortical, ventricular, and global brain volumes, and z-scores of memory and executive functioning were calculated. Linear regression analysis was used to estimate associations of homocysteine (per standard deviation increase) and hyperhomocysteinemia (HHCY) with brain volumes, memory, and executive functioning at follow-up, adjusted for baseline brain volume, memory, and executive functioning, respectively, and age, sex, and vascular risk factors. Furthermore, interaction terms between homocysteine and age (continuous) were added. Results Significant interactions were observed between total plasma homocysteine (tHcy) and age with cortical, ventricular, and global brain volume (for all three measures: P <.05), and between HHCY and age with executive functioning (P = .04), and results were stratified by age. In patients aged =65 years, increasing tHcy level and HHCY were significantly associated with progression of ventricular enlargement (B = 0.07%, 95% confidence interval [CI]: 0.01% to 0.13% and B = 0.16%, 95% CI: 0.01% to 0.31%, respectively) and with a decline in executive function (B = -0.29, 95% CI: -0.54 to -0.04 and B = -0.84, 95% CI: -1.37 to -0.32, respectively). Conclusion Elevated tHcy was related to progression of ventricular enlargement and increased the risk for a decline in executive functioning in older persons
B vitamins and n-3 fatty acids for brain development and function: review of human studies
Rest, O. van de; Hooijdonk, L.W.A. ; Doets, E.L. ; Schiepers, O.J.G. ; Eilander, J.H.C. ; Groot, C.P.G.M. de - \ 2012
Annals of Nutrition & Metabolism 60 (2012)4. - ISSN 0250-6807 - p. 272 - 292.
alpha-linolenic acid - long-chain omega-3-fatty-acids - randomized controlled-trials - quality-of-life - depressive symptoms - docosahexaenoic acid - alzheimers-disease - folic-acid - cognitive function - fish consumption
Background: Nutrition is one of many factors that affect brain development and functioning, and in recent years the role of certain nutrients has been investigated. B vitamins and n–3 polyunsaturated fatty acids (PUFA) are two of the most promising and widely studied nutritional factors. Methods: In this review, we provide an overview of human studies published before August 2011 on how vitamin B6, folate, vitamin B12 and n–3 PUFA may affect the brain, their nutrient status and the existing evidence for an association between these nutrients and brain development, brain functioning and depression during different stages of the life cycle. Results: No recommendation can be given regarding a role of B vitamins, either because the number of studies on B vitamins is too limited (pregnant and lactating women and children) or the studies are not consistent (adults and elderly). For n–3 PUFA, observational evidence may be suggestive of a beneficial effect; however, this has not yet been sufficiently replicated in randomized controlled trials (RCTs). Conclusions: We found that the existing evidence from observational studies as well as RCTs is generally too limited and contradictory to draw firm conclusions. More research is needed, particularly a combination of good-quality long-term prospective studies and well-designed RCTs
Self-reported energy intake by FFQ compared with actual energy intake to maintain body weight in 516 adults
Siebelink, E. ; Geelen, A. ; Vries, J.H.M. de - \ 2011
The British journal of nutrition 106 (2011)2. - ISSN 0007-1145 - p. 274 - 281.
food-frequency questionnaire - doubly labeled water - flow-mediated vasodilation - breast-cancer - folic-acid - validation - humans - bioavailability - cholesterol - nutrition
It is generally assumed that a FFQ is not suitable to estimate the absolute levels of individual energy intake. However, in epidemiological studies, reported nutrients by FFQ are often corrected for this intake. The objective of the present study was to assess how accurately participants report their energy intakes by FFQ. We compared reported energy intake with actual energy intake needed to maintain stable body weights during eleven controlled dietary trials. FFQ were developed to capture at least 90 % of energy intake. Participants, 342 women and 174 men, with a mean BMI of 22·8 (sd 3·1) kg/m2 filled out the FFQ just before the trials. Energy intakes during the trials were calculated from provided foods and reported free-food items, representing 90 and 10 % of energy intake, respectively. Mean reported energy intake was 97·5 (sd 12·7) % of actual energy intake during the trials; it was 98·9 (sd 15·2) % for women and 94·7 (sd 16·3) % for men (P = 0·004 for difference between sexes). Correlation coefficients between reported and actual energy intakes were 0·82 for all participants, 0·74 for women and 0·80 for men. Individual reported energy intake as a percentage of actual intake ranged from 56·3 to 159·6 % in women and from 43·8 to 151·0 % in men. In conclusion, the FFQ appeared to be accurate for estimating the mean level of energy intakes of these participants and for ranking them according to their intake. However, the large differences found on the individual level may affect the results of epidemiological studies in an unknown direction if nutrients are corrected for energy intakes reported by FFQ
Tailored preconceptional dietary and lifestyle counselling in a tertiary outpatient clinic in the Netherlands
Hammiche, F. ; Laven, J.S.E. ; Mil, N. van; Cock, M. ; Vries, J.H.M. de; Lindemans, J. ; Steegers, E.A.P. ; Steegers-Theunissen, R.P.M. - \ 2011
Human Reproduction 26 (2011)9. - ISSN 0268-1161 - p. 2432 - 2441.
adverse perinatal outcomes - folic-acid - alcohol-consumption - fetal-growth - risk-factors - spontaneous-abortion - maternal overweight - general-population - physical-activity - seminal plasma
BACKGROUND Adverse reproductive performance has been linked to unhealthy dietary intake and lifestyles. Our objectives were to investigate the prevalence of unhealthy dietary intake and lifestyles before conception and to evaluate whether tailored preconception counselling modifies these behaviours. METHODS Between October 2007 and April 2009, 419 couples received tailored preconception dietary and lifestyle counselling at the outpatient clinic of Obstetrics and Gynaecology of the Erasmus University Medical Center Rotterdam, the Netherlands. A subgroup (n = 110 couples) was counselled twice with a fixed time interval of 3 months. Self-administered questionnaires were used for tailored dietary and lifestyle counselling. A cumulative score based on six Dutch dietary guidelines was displayed in the personal Preconception Dietary Risk score (PDR score). In a similar manner, the Rotterdam Reproduction Risk score (R3 score) was calculated from lifestyle factors (women: 13 items, men: 10 items). Univariate and paired tests were used. RESULTS Most couples (93.8%) were subfertile. At the second counselling, the percentage consuming the recommended intake of fruit had increased from 65 to 80 in women and from 49 to 68 in men and the percentage of women getting the recommended intake of fish increased from 39 to 52. As a consequence, the median PDR score was decreased [women: 2.6 (95% CI 2.4–2.9) to 2.4 (95% CI 2.1–2.6), men: 2.5 (95% CI 2.3–2.7) to 2.2 (95% CI 1.9–2.4), both P <0.05]. The median R3 scores were also lower [women: 4.7 (95% CI 4.3–5.0) to 3.1 (95% CI 2.8–3.4), men: 3.0 (95% CI 2.8–3.3) to 2.0 (95% CI 1.7–2.3), both P <0.01] due to less alcohol use (-14.6%), more physical exercise and folic acid use in women, and less alcohol use in men (-19.4%) (all P <0.01). The R3 scores in women and men were decreased in all ethnicity, educational level, neighbourhood and BMI categories. However, low educated women appeared to show a larger reduction than better educated women and men with a normal BMI to show a larger decrease than overweight men. The reduction in the PDR score of women was similar in both ethnic groups. More than 85% women and men found the counselling useful and around 70% would recommend it to others. CONCLUSIONS Tailored preconception counselling about unhealthy dietary and lifestyle behaviours of subfertile couples in an outpatient tertiary clinic is feasible and seems to decrease the prevalence of harmful behaviours in the short term. These results with subfertile couples are promising and illustrate their opportunities to contribute to reproductive performance and pregnancy outcome.
The process of setting micronutrient recommendations: a cross-European comparison of nutrition-related scientific advisory bodies
Timotijevic, L. ; Barnett, J. ; Brown, K. ; Shepherd, R. ; Fernandez-Celemin, L. ; Domolki, L. ; Ruprich, J. ; Dhonukshe-Rutten, R.A.M. ; Sonne, A.M. ; Hermoso, M. ; Koletzko, B. ; Frost-Andersen, L. ; Timmer, A. ; Raats, M.M. - \ 2011
Public Health Nutrition 14 (2011)4. - ISSN 1368-9800 - p. 716 - 728.
folic-acid - health-policy - risk - science - perspectives - expertise - politics - context - trial
Objective - To examine the workings of the nutrition-related scientific advisory bodies in Europe, paying particular attention to the internal and external contexts within which they operate. Design - Desk research based on two data collection strategies: a questionnaire completed by key informants in the field of micronutrient recommendations and a case study that focused on mandatory folic acid (FA) fortification. Setting - Questionnaire-based data were collected across thirty-five European countries. The FA fortification case study was conducted in the UK, Norway, Denmark, Germany, Spain, Czech Republic and Hungary. Results - Varied bodies are responsible for setting micronutrient recommendations, each with different statutory and legal models of operation. Transparency is highest where there are standing scientific advisory committees (SAC). Where the standing SAC is created, the range of expertise and the terms of reference for the SAC are determined by the government. Where there is no dedicated SAC, the impetus for the development of micronutrient recommendations and the associated policies comes from interested specialists in the area. This is typically linked with an ad hoc selection of a problem area to consider, lack of openness and transparency in the decisions and over-reliance on international recommendations. Conclusions - Even when there is consensus about the science behind micronutrient recommendations, there is a range of other influences that will affect decisions about the policy approaches to nutrition-related public health. This indicates the need to document the evidence that is drawn upon in the decisions about nutrition policy related to micronutrient intake
The preconception Mediterranean dietary pattern in couples undergoing in vitro fertilization/intracytoplasmic sperm injection treatment increases the chance of pregnancy
Vujkovic, M. ; Vries, J.H.M. de; Lindemans, J. ; Macklon, N.S. ; Spek, P.J. van der; Steegers, E.A.P. ; Steegers-Theunissen, R.P.M. - \ 2010
Fertility and Sterility 94 (2010)6. - ISSN 0015-0282 - p. 2096 - 2101.
life-style factors - folic-acid - energy-intake - homocysteine - fertility - folate - implantation - performance - population - impact
Objective: To investigate associations between preconception dietary patterns and IVF/intracytoplasmic sperm injection (ICSI) outcomes validated by biomarkers of the homocysteine pathway. Design: Observational prospective study. Setting: A tertiary referral fertility clinic at the Erasmus University Medical Centre, Rotterdam, The Netherlands. Patient(s): One hundred sixty-one couples undergoing IVF/ICSI treatment. Intervention(s): No interventions other than the Dutch governmental recommendation of folic acid. Main Outcome Measure(s): Dietary patterns, blood and follicular fluid concentrations of folate, vitamin B12, vitamin B6, homocysteine, and fertilization rate, embryo quality, and pregnancy. Result(s): In women, two dietary patterns were identified. The "health conscious-low processed" dietary pattern (variation explained 12.1%) was characterized by high intakes of fruits, vegetables, fish, and whole grains and low intakes of snacks, meats, and mayonnaise, and positively correlated with red blood cell folate (beta=0.07). The "Mediterranean" dietary pattern (variation explained 9.1%), that is, high intakes of vegetable oils, vegetables, fish, and legumes and low intakes of snacks, was positively correlated with red blood cell folate (beta=0.13), and vitamin B6 in blood (beta=0.09) and follicular fluid (beta=0.18). High adherence by the couple to the "Mediterranean" diet increased the probability of pregnancy, odds ratio 1.4 (95% confidence interval 1.0-1.9). Conclusion(s): A preconception "Mediterranean" diet by couples undergoing IVF/ICSI treatment contributes to the success of achieving pregnancy. (Fertil Steril (R) 2010; 94: 2096-101. (C) 2010 by American Society for Reproductive Medicine.)
The effects of iron fortification on the gut microbiota in African children: a randomized controlled trial in Côte d'Ivoire
Zimmermann, M.B. ; Chassard, C. ; Rohner, F. ; N'goran, E.K. ; Nindjin, C. ; Dostal, A. ; Utzinger, J. ; Ghattas, H. ; Lacroix, C. ; Hurrell, R.F. - \ 2010
American Journal of Clinical Nutrition 92 (2010)6. - ISSN 0002-9165 - p. 1406 - 1415.
gradient gel-electrophoresis - 16s ribosomal-rna - routine prophylactic supplementation - inflammatory-bowel-disease - placebo-controlled trial - lactic-acid bacteria - fecal microbiota - fermented milk - folic-acid - pcr
Background: Iron is essential for the growth and virulence of many pathogenic enterobacteria, whereas beneficial barrier bacteria, such as lactobacilli, do not require iron. Thus, increasing colonic iron could select gut microbiota for humans that are unfavorable to the host. Objective: The objective was to determine the effect of iron fortification on gut microbiota and gut inflammation in African children. Design: In a 6-mo, randomized, double-blind, controlled trial, 6–14-y-old Ivorian children (n = 139) received iron-fortified biscuits, which contained 20 mg Fe/d, 4 times/wk as electrolytic iron or nonfortified biscuits. We measured changes in hemoglobin concentrations, inflammation, iron status, helminths, diarrhea, fecal calprotectin concentrations, and microbiota diversity and composition (n = 60) and the prevalence of selected enteropathogens. Results: At baseline, there were greater numbers of fecal enterobacteria than of lactobacilli and bifidobacteria (P <0.02). Iron fortification was ineffective; there were no differences in iron status, anemia, or hookworm prevalence at 6 mo. The fecal microbiota was modified by iron fortification as shown by a significant increase in profile dissimilarity (P <0.0001) in the iron group as compared with the control group. There was a significant increase in the number of enterobacteria (P <0.005) and a decrease in lactobacilli (P <0.0001) in the iron group after 6 mo. In the iron group, there was an increase in the mean fecal calprotectin concentration (P <0.01), which is a marker of gut inflammation, that correlated with the increase in fecal enterobacteria (P <0.05). Conclusions: Anemic African children carry an unfavorable ratio of fecal enterobacteria to bifidobacteria and lactobacilli, which is increased by iron fortification. Thus, iron fortification in this population produces a potentially more pathogenic gut microbiota profile, and this profile is associated with increased gut inflammation. This trial was registered at controlled-trials.com as ISRCTN21782274.
Physiological responses to folate overproduction in Lactobacillus plantarum WCFS1
Wegkamp, A. ; Mars, A.E. ; Faijes, M. ; Molenaar, D. ; Vos, R.C.H. de; Klaus, M.J. ; Hanson, A.D. ; Vos, W.M. de; Smid, E.J. - \ 2010
Microbial Cell Factories 9 (2010). - ISSN 1475-2859 - 14 p.
lactic-acid bacteria - lactococcus-lactis - escherichia-coli - streptococcus-cremoris - growth-rate - folic-acid - expression - protein - biosynthesis - recombinant
Background Using a functional genomics approach we addressed the impact of folate overproduction on metabolite formation and gene expression in Lactobacillus plantarum WCFS1. We focused specifically on the mechanism that reduces growth rates in folate-overproducing cells. Results Metabolite formation and gene expression were determined in a folate-overproducing- and wild-type strain. Differential metabolomics analysis of intracellular metabolite pools indicated that the pool sizes of 18 metabolites differed significantly between these strains. The gene expression profile was determined for both strains in pH-regulated chemostat culture and batch culture. Apart from the expected overexpression of the 6 genes of the folate gene cluster, no other genes were found to be differentially expressed both in continuous and batch cultures. The discrepancy between the low transcriptome and metabolome response and the 25% growth rate reduction of the folate overproducing strain was further investigated. Folate production per se could be ruled out as a contributing factor, since in the absence of folate production the growth rate of the overproducer was also reduced by 25%. The higher metabolic costs for DNA and RNA biosynthesis in the folate overproducing strain were also ruled out. However, it was demonstrated that folate-specific mRNAs and proteins constitute 8% and 4% of the total mRNA and protein pool, respectively. Conclusion Folate overproduction leads to very little change in metabolite levels or overall transcript profile, while at the same time the growth rate is reduced drastically. This shows that Lactobacillus plantarum WCFS1 is unable to respond to this growth rate reduction, most likely because the growth-related transcripts and proteins are diluted by the enormous amount of gratuitous folate-related transcripts and proteins.
Supplementation with engineered Lactococcus lactis improves the folate status in deficient rats
LeBlanc, J.G. ; Sybesma, W.F.H. ; Starrenburg, M. ; Sesma, F. ; Vos, W.M. de; Giori, G.S. de; Hugenholtz, J. - \ 2010
Nutrition 26 (2010)7. - ISSN 0899-9007 - p. 835 - 841.
neural-tube defects - folic-acid - riboflavin status - plasma homocysteine - dietary-folate - bacteria - bioavailability - prevention - vitamin - propionibacteria
Objective: The aim of this study was to establish the bioavailability of different folates produced by engineered Lactococcus lactis strains using a rodent depletion-repletion bioassay. Methods: Rats were fed a folate-deficient diet, which produces a reversible subclinical folate deficiency, supplemented with different L lactis cultures that were added as the only source of folate. Three bacterial strains that overexpressed the folC, folKE, or folC + KE genes were used. These strains produce folates with different poly glutamyl tail lengths. The growth response of the rats and the concentration of folates in different organs and blood samples were monitored. Results: The folate produced by the engineered strains was able to compensate the folate depletion in the diet and showed similar bioavailability compared with commercial folic acid that is normally used for food fortification. Folate concentrations in organ and blood samples increased significantly in animals that received the folate-producing strains compared with those that did not receive bacterial supplementation. Hematologic studies also showed that administration of the L towns strains was able to revert a partial megaloblastic anemia caused by folate deficiency. No significant differences were observed in the bioavailability of folates containing different glutamyl tail lengths. Conclusion: To our knowledge, this is the first study that demonstrated that folates produced by engineered lactic acid bacteria represent a bioavailable source of this essential vitamin. (C) 2010 Elsevier Inc. All rights reserved.
Associations between dietary patterns and semen quality in men undergoing IVF/ICSI treatment
Vujkovic, M. ; Vries, J.H.M. de; Dohle, G.R. ; Bonsel, G.J. ; Lindemans, J. ; Macklon, N.S. ; Spek, P.J. van der; Steegers, E.A.P. ; Steegers-Theunissen, R.P.M. - \ 2009
Human Reproduction 24 (2009)6. - ISSN 0268-1161 - p. 1304 - 1312.
male factor subfertility - male-infertility - seminal plasma - double-blind - vitamin-e - fundamental principles - energy physiology - controlled-trial - zinc-sulfate - folic-acid
BACKGROUND: This study investigates whether dietary patterns, substantiated by biomarkers, are associated with semen quality. METHODS: In 161 men of subfertile couples undergoing in vitro fertilization treatment in a tertiary referral clinic in Rotterdam, the Netherlands, we assessed nutrient intakes and performed principal component factor analysis to identify dietary patterns. Total homocysteine (tHcy), folate, vitamin B12 and B6 were measured in blood and seminal plasma. Semen quality was assessed by sperm volume, concentration, motility, morphology and DNA fragmentation index (DFI). Linear regression models analyzed associations between dietary patterns, biomarkers and sperm parameters, adjusted for age, body mass index (BMI), smoking, vitamins and varicocele. RESULTS: The ‘Health Conscious’ dietary pattern shows high intakes of fruits, vegetables, fish and whole grains. The ‘Traditional Dutch’ dietary pattern is characterized by high intakes of meat, potatoes and whole grains and low intakes of beverages and sweets. The ‘Health Conscious’ diet was inversely correlated with tHcy in blood (ß = –0.07, P = 0.02) and seminal plasma (ß = –1.34, P = 0.02) and positively with vitamin B6 in blood (ß = 0.217, P = 0.01). An inverse association was demonstrated between the ‘Health Conscious’ diet and DFI (ß = –2.81, P = 0.05). The ‘Traditional Dutch’ diet was positively correlated with red blood cell folate (ß = 0.06, P = 0.04) and sperm concentration (ß = 13.25, P = 0.01). CONCLUSIONS: The ‘Health Conscious’ and ‘Traditional Dutch’ dietary pattern seem to be associated with semen quality in men of subfertile couples.
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