Anouk Geelen

Dietary Flavonol Intake May Lower Stroke Risk in Men and Women

Flavonols are strong antioxidants in plant foods and tea is a major dietary source. There is evidence from prospective cohort studies that tea and flavonols are inversely related to stroke incidence. We conducted a metaanalysis of prospective cohort studies to assess quantitatively the strength of the association between flavonol intake and stroke incidence. Prospective cohort studies with data from individuals free of cardiovascular diseases (CVD) or stroke at baseline were included in the metaanalysis. Persons were followed for between 6 and 28 y. Data from 6 cohorts involving 111,067 persons with at least 2155 nonfatal and fatal cases were pooled. A random effects model was used. In all studies included, adjustments were made for major CVD risk factors except for 2 that did not adjust for alcohol and energy intake. A high intake of flavonols compared with a low intake was inversely associated with nonfatal and fatal stroke with a pooled relative risk of 0.80 (95% CI: 0.65, 0.98). Visual inspection of Beggs funnel plot and Eggers test (P = 0.01) indicated potential publication bias. We conclude that flavonols may reduce stroke risk.

Intake of n-3 fatty acids from fish does not lower serum concentrations of C-reactive protein in healthy subjects

Objective: High-sensitivity C-reactive protein (CRP), a marker of systemic inflammation, is a powerful predictor of cardiovascular risk. We hypothesised that n-3 fatty acids reduce underlying inflammatory processes and consequently CRP concentrations in healthy middle-aged subjects.Design: Placebo-controlled, double-blind study.Subjects: A total of 43 men and 41 postmenopausal women aged 50–70 y. Before and after intervention, we measured serum CRP concentrations with an enzyme immunoassay.Interventions: Capsules with either 3.5 g/day fish oil (1.5 g/day n-3 fatty acids) or placebo for 12 weeks.Results: The median CRP change in the fish oil group did not significantly differ from that in the placebo group (0.01 vs −0.17 mg/l, P = 0.057).Conclusion: The currently available data —including ours— do not support that beneficial effects on CRP are involved in a mechanism explaining the protective effect on heart disease risk of n-3 fatty acids as present in fish.Sponsorship: Wageningen Centre for Food Sciences.

The Dutch Healthy Diet index (DHD-index): an instrument to measure adherence to the Dutch Guidelines for a Healthy Diet

BackgroundThe objective was to develop an index based on the Dutch Guidelines for a healthy Diet of 2006 that reflects dietary quality and to apply it to the Dutch National Food Consumption Survey (DNFCS) to examine the associations with micronutrient intakes.MethodsA total of 749 men and women, aged 19–30 years, contributed two 24-hour recalls and additional questionnaires in the DNFCS of 2003. The Dutch Healthy Diet index (DHD-index) includes ten components representing the ten Dutch Guidelines for a Healthy Diet. Per component the score ranges between zero and ten, resulting in a total score between zero (no adherence) and 100 (complete adherence).ResultsThe mean ± SD of the DHD-index was 60.4 ± 11.5 for women and 57.8 ± 10.8 for men (P for difference = 0.002). Each component score increased across the sex-specific quintiles of the DHD-index. An inverse association was observed between the sex-specific quintiles of the DHD-index and total energy intake. Calcium, riboflavin, and vitamin E intake decreased with increasing DHD-index, an inverse association which disappeared after energy adjustment. Vitamin C showed a positive association across quintiles, also when adjusted for energy. For folate, iron, magnesium, potassium, thiamin, and vitamin B6 a positive association emerged after adjustment for energy.ConclusionsThe DHD-index is capable of ranking participants according to their adherence to the Dutch Guidelines for a Healthy Diet by reflecting variation in nine out of ten components that constitute the index when based on two 24-hour recalls. Furthermore, the index showed to be a good measure of nutrient density of diets.

Identification of potential serum biomarkers of inflammation and lipid modulation that are altered by fish oil supplementation in healthy volunteers.

Long chain n‐3 polyunsaturated fatty acids (n‐3 LCPUFA) lower risk of coronary heart disease (CHD), but mechanisms are not well understood. We used proteomics to identify human serum proteins that are altered by n‐3 LCPUFA. Such proteins could identify pathways whereby they affect CHD. Eighty‐one healthy volunteers entered a double blind randomised trial to receive 3.5 g of fish oil or 3.5 g of high oleic sunflower oil daily. Serum was collected before and after 6 wk of intervention. Serum was analysed by proteomics using 2‐DE. Proteins that were differentially regulated were identified by MS. We also analysed serum apolipoprotein A1 (apo A1), high‐density lipoprotein (HDL) particle size and haptoglobin. Serum levels of apo A1, apo L1, zinc‐α‐2‐glycoprotein, haptoglobin precursor, α‐1‐antitrypsin precursor, antithrombin III‐like protein, serum amyloid P component and haemopexin were significantly downregulated (all p<0.05) by fish oil compared with high oleic sunflower oil supplementation. Fish oil supplementation caused a significant shift towards the larger, more cholesterol‐rich HDL2 particle. The alterations in serum proteins and HDL size imply that fish oil activates anti‐inflammatory and lipid modulating mechanisms believed to impede the early onset of CHD. These proteins are potential diagnostic biomarkers to assess the mechanisms whereby fish oil protects against CHD in humans.

No effect of fish oil supplementation on serum inflammatory markers and their interrelationships: a randomized controlled trial in healthy, middle-aged individuals.

Background:A high intake of n-3 polyunsaturated fatty acids (PUFAs), mainly present in fish, may be associated with decreased inflammation. Previous intervention studies on fish PUFA and inflammatory markers in healthy individuals did not analyze a broad spectrum of inflammatory cytokines, chemokines and cell adhesion molecules, or their interrelationships. Therefore, we determined the effects of fish oil supplementation on 19 serum inflammatory markers and their interrelationships in healthy, middle-aged individuals.Methods:Individuals (n=77) aged 50–70 years completed a randomized, double-blind placebo-controlled intervention study. Participants received 3.5 g/day fish oil (1.5 g/day total n-3 PUFA) (n=39) or placebo (high oleic sunflower oil) (n=38) for 12 weeks. Serum concentrations of 19 inflammatory markers were determined using a multiplex immunoassay before and after intervention. Changes in concentrations were analyzed using analysis of covariance and differences in patterns in inflammatory markers between the fish oil and placebo group were analyzed by principal component analysis.Results:Fish oil supplementation did not significantly affect serum concentrations of cytokines, chemokines or cell adhesion molecules as compared with placebo. However, there was a trend for all inflammatory markers to increase after fish oil supplementation. PCA did not result in markedly distinctive patterns of inflammatory markers for the fish oil and placebo group.Conclusion:In conclusion, this 12-week randomized, double-blind placebo-controlled intervention trial did not show that 1.5 g/day n-3 PUFA significantly affected the serum inflammatory response in healthy individuals, nor did patterns of inflammatory markers. Thus, a healthy middle-aged population may not benefit from fish oil as an anti-inflammatory agent.

Two non-consecutive 24 h recalls using EPIC-Soft software are sufficiently valid for comparing protein and potassium intake between five European centres – results from the European Food Consumption Validation (EFCOVAL) study

The use of two non-consecutive 24 h recalls using EPIC-Soft for standardised dietary monitoring in European countries has previously been proposed in the European Food Consumption Survey Method consortium. Whether this methodology is sufficiently valid to assess nutrient intake in a comparable way, among populations with different food patterns in Europe, is the subject of study in the European Food Consumption Validation consortium. The objective of the study was to compare the validity of usual protein and K intake estimated from two non-consecutive standardised 24 h recalls using EPIC-Soft between five selected centres in Europe. A total of 600 adults, aged 45-65 years, were recruited in Belgium, the Czech Republic, France, The Netherlands and Norway. From each participant, two 24 h recalls and two 24 h urines were collected. The mean and distribution of usual protein and K intake, as well as the ranking of intake, were compared with protein and K excretions within and between centres. Underestimation of protein (range 2-13%) and K (range 4-17%) intake was seen in all centres, except in the Czech Republic. We found a fair agreement between prevalences estimated based on the intake and excretion data at the lower end of the usual intake distribution (< 10% difference), but larger differences at other points. Protein and K intake was moderately correlated with excretion within the centres (ranges = 0·39-0·67 and 0·37-0·69, respectively). These were comparable across centres. In conclusion, two standardised 24 h recalls (EPIC-Soft) appear to be sufficiently valid for assessing and comparing the mean and distribution of protein and K intake across five centres in Europe as well as for ranking individuals.

Opposing associations of serum n‐3 and n‐6 polyunsaturated fatty acids with colorectal adenoma risk: An endoscopy‐based case–control study

Several human and animal studies have shown that n‐3 polyunsaturated fatty acids (PUFA) might be associated with a decreased risk, whereas other studies showed that n‐6 PUFA may be associated with an increased risk of colorectal cancer. However, results from these studies are not consistent. We evaluated the associations between serum n‐3 and n‐6 PUFA levels and colorectal adenoma risk in an endoscopy‐based case–control study, conducted in The Netherlands between 1997 and 2002. We included 363 cases of colorectal adenomas and 498 adenoma‐free controls. Serum fatty acids were measured in cholesteryl esters. Logistic regression models were used to calculate odds ratios (OR), which were adjusted for age, gender and alcohol intake. Total serum n‐3 PUFA levels were inversely associated with colorectal adenoma risk, the OR comparing the third tertile with the first tertile was 0.67 [95% confidence interval (CI) 0.46–0.96, p for trend = 0.03]. Serum eicosapentaenoic acid (EPA; C20:5n‐3) and docosahexaenoic acid (DHA; C22:6n‐3) and the n‐3/n‐6 ratio were inversely associated with colorectal adenoma risk, but these were not statistically significant. In contrast, the risk of colorectal adenomas was increased by total n‐6 PUFA with an OR of 1.68 (95% CI, 1.17–2.42, p for trend = 0.006) and by linoleic acid (LA; C18:2n‐6) with an OR of 1.65 (95% CI, 1.15–2.38, p for trend = 0.007). This is the first observational study that simultaneously finds an inverse association of serum n‐3 PUFA and a positive association of n‐6 PUFA with colorectal adenoma risk.

Adherence to a Healthy Diet According to the World Health Organization Guidelines and All-Cause Mortality in Elderly Adults From Europe and the United States

The World Health Organization (WHO) has formulated guidelines for a healthy diet to prevent chronic diseases and postpone death worldwide. Our objective was to investigate the association between the WHO guidelines, measured using the Healthy Diet Indicator (HDI), and all-cause mortality in elderly men and women from Europe and the United States. We analyzed data from 396,391 participants (42% women) in 11 prospective cohort studies who were 60 years of age or older at enrollment (in 1988-2005). HDI scores were based on 6 nutrients and 1 food group and ranged from 0 (least healthy diet) to 70 (healthiest diet). Adjusted cohort-specific hazard ratios were derived by using Cox proportional hazards regression and subsequently pooled using random-effects meta-analysis. During 4,497,957 person-years of follow-up, 84,978 deaths occurred. Median HDI scores ranged from 40 to 54 points across cohorts. For a 10-point increase in HDI score (representing adherence to an additional WHO guideline), the pooled adjusted hazard ratios were 0.90 (95% confidence interval (CI): 0.87, 0.93) for men and women combined, 0.89 (95% CI: 0.85, 0.92) for men, and 0.90 (95% CI: 0.85, 0.95) for women. These estimates translate to an increased life expectancy of 2 years at the age of 60 years. Greater adherence to the WHO guidelines is associated with greater longevity in elderly men and women in Europe and the United States.

Effect of n-3 fatty acids on heart rate variability and baroreflex sensitivity in middle-aged subjects.

BACKGROUND N-3 fatty acids may reduce the risk of sudden death by preventing life-threatening cardiac arrhythmias. Heart rate variability (HRV) and baroreflex sensitivity (BRS) reflect cardiac autonomic regulation; reduced values predict arrhythmic events and mortality. Effects of n-3 fatty acids on these risk indicators of arrhythmia have not been widely studied. We investigated the effect of supplemental intake of n-3 fatty acids on HRV and BRS in apparently healthy subjects aged 50 to 70 years. METHODS After a run-in period of 4 weeks, 84 subjects were randomized to receive capsules with either 3.5 g of fish oil or placebo oil daily for 12 weeks. Before and after intervention, electrocardiograms and blood pressure were recorded for 10 minutes with standardized respiration of 15 breaths/min. The SD of the duration of all normal RR intervals (SDNN10) and the root mean square successive differences (RMSSD10) were calculated from the 10-minute recordings. We also computed low frequency power (LF) and high frequency power (HF). BRS was computed by integrating the spectral systolic blood pressure to interbeat-interval transfer function in the 0.05- to 0.15-Hz band. RESULTS The different measures of HRV and BRS did not significantly improve with the intake of n-3 fatty acids. SDNN10 decreased by 3.05 ms or 7.7% (95% CI, -8.91-2.82 ms), and BRS decreased by 0.92 ms/mm Hg or 0.1% (95% CI, -2.66-0.81 ms/mm Hg) in the fish oil group compared with the placebo group. CONCLUSIONS N-3 fatty acids have no effect on HRV from short-term recordings and BRS in apparently healthy subjects.

Socio-economic determinants of micronutrient intake and status in Europe: a systematic review

OBJECTIVE To provide the evidence base for targeted nutrition policies to reduce the risk of micronutrient/diet-related diseases among disadvantaged populations in Europe, by focusing on: folate, vitamin B12, Fe, Zn and iodine for intake and status; and vitamin C, vitamin D, Ca, Se and Cu for intake. DESIGN MEDLINE and Embase databases were searched to collect original studies that: (i) were published from 1990 to 2011; (ii) involved >100 subjects; (iii) had assessed dietary intake at the individual level; and/or (iv) included best practice biomarkers reflecting micronutrient status. We estimated relative differences in mean micronutrient intake and/or status between the lowest and highest socio-economic groups to: (i) evaluate variation in intake and status between socio-economic groups; and (ii) report on data availability. SETTING Europe. SUBJECTS Children, adults and elderly. RESULTS Data from eighteen publications originating primarily from Western Europe showed that there is a positive association between indicators of socio-economic status and micronutrient intake and/or status. The largest differences were observed for intake of vitamin C in eleven out of twelve studies (5-47 %) and for vitamin D in total of four studies (4-31 %). CONCLUSIONS The positive association observed between micronutrient intake and socio-economic status should complement existing evidence on socio-economic inequalities in diet-related diseases among disadvantaged populations in Europe. These findings could provide clues for further research and have implications for public health policy aimed at improving the intake of micronutrients and diet-related diseases.