Amy Jennings

Intakes of Anthocyanins and Flavones Are Associated with Biomarkers of Insulin Resistance and Inflammation in Women

Although laboratory data suggest that several flavonoid subclasses are involved in glucose metabolism, limited clinical and epidemiologic data are available. The current study examined associations between habitual intake of flavonoid subclasses, insulin resistance, and related inflammatory biomarkers. In a cross-sectional study of 1997 females aged 18-76 y, intakes of total flavonoids and their subclasses (flavanones, anthocyanins, flavan-3-ols, polymeric flavonoids, flavonols, flavones) were calculated from food frequency questionnaires using an extended USDA database. Fasting serum glucose, insulin, high-sensitivity C-reactive protein (hs-CRP; n = 1432), plasminogen activator inhibitor-1 (n = 843), and adiponectin (n = 1452) concentrations were measured. In multivariable analyses, higher anthocyanin and flavone intake were associated with significantly lower peripheral insulin resistance [homeostasis model assessment of insulin resistance; quintile 5 (Q5) to Q1 = -0.1, P-trend = 0.04 for anthocyanins and flavones] as a result of a decrease in insulin concentrations (Q5-Q1 = -0.7 μU/mL, P-trend = 0.02 anthocyanins; Q5-Q1 = -0.5 μU/mL, P-trend = 0.02 flavones). Higher anthocyanin intake was also associated with lower hs-CRP concentrations (Q5-Q1 = -0.3 mg/L, P-trend = 0.04), whereas those in the highest quintile of flavone intake had improved adiponectin concentrations (Q5-Q1 = 0.7 μg/L, P-trend = 0.01). Anthocyanin-rich foods were also associated with lower insulin and inflammation levels. No significant associations were observed for total or other flavonoid subclasses. Higher intakes of both anthocyanins and flavones were associated with improvements in insulin resistance and hs-CRP. These associations were found with intakes readily achieved in the diet. The observed reduction in insulin concentrations was similar to that reported previously for other lifestyle factors. Dose-response trials are needed to ascertain optimal intakes for the potential reduction of type 2 diabetes risk.

Diet Quality Is Independently Associated with Weight Status in Children Aged 9–10 Years

Although energy imbalance is key to the development of childhood obesity, the association between different dietary components, reflected in diet quality scores, and childrens weight status has not been extensively studied. The current study determined if diet quality, characterized according to 3 predefined scores, was associated with weight status in a population-based sample of 9- to 10-y-old British children, independently of factors previously associated with weight status. In a cross-sectional study of 1700 children (56% girls), data from 4-d food diaries were used to calculate 3 diet quality scores modified to be reflective of childrens diets: the Diet Quality Index (DQI), Healthy Diet Indicator (HDI), and Mediterranean Diet Score (MDS). Physical activity was measured with 7-d accelerometery, and height, weight, waist, and bio-impedance were objectively measured and used to calculate weight status variables. After multiple adjustments, including physical activity and overall energy density, higher DQI and HDI scores were significantly associated with improved weight status. Comparing extreme quintiles of the scores revealed the DQI and HDI were associated with lower waist circumference (-3.0%, P = 0.005 and -2.5%, P = 0.033, respectively), and lower body fat (-5.1%, P = 0.023 and -4.9%, P = 0.026, respectively). The DQI was also associated with lower weight (-5.9%; P = 0.002) and BMI (-4.2%; P = 0.004). No significant associations were observed with the MDS. These findings suggest that diet quality is independently associated with childrens weight status. Future work should consider if diet quality scores could be key components of interventions designed to reduce obesity in children.

Habitual flavonoid intakes are positively associated with bone mineral density in women

Dietary flavonoids exert bone‐protective effects in animal models, but there is limited information on the effect of different flavonoid subclasses on bone health in humans. The aim of this observational study was to examine the association between habitual intake of flavonoid subclasses with bone mineral density (BMD) in a cohort of female twins. A total of 3160 women from the TwinsUK adult twin registry participated in the study. Habitual intakes of flavonoids and subclasses (flavanones, anthocyanins, flavan‐3‐ols, polymers, flavonols, and flavones) were calculated from semiquantitative food frequency questionnaires using an updated and extended U.S. Department of Agriculture (USDA) database. Bone density was measured using dual‐energy X‐ray absorptiometry. In multivariate analyses, total flavonoid intake was positively associated with higher BMD at the spine but not at the hip. For the subclasses, the magnitude of effect was greatest for anthocyanins, with a 0.034 g/cm2 (3.4%) and 0.029 g/cm2 (3.1%) higher BMD at the spine and hip, respectively, for women in the highest intake quintile compared to those in the lowest. Participants in the top quintile of flavone intake had a higher BMD at both sites; 0.021 g/cm2 (spine) and 0.026 g/cm2 (hip). At the spine, a greater intake of flavonols and polymers was associated with a higher BMD (0.021 and 0.024 g/cm2, respectively), whereas a higher flavanone intake was positively associated with hip BMD (0.008 g/cm2). In conclusion, total flavonoid intake was positively associated with BMD, with effects observed for anthocyanins and flavones at both the hip and spine, supporting a role for flavonoids present in plant‐based foods on bone health.

Associations between eating frequency, adiposity, diet, and activity in 9-10 year old healthy-weight and centrally obese children.

The rising prevalence of childhood obesity is a key public health issue worldwide. Increased eating frequency (EF) is one aspect of diet that has been beneficially associated with obesity, although the mechanisms are unclear. The aims of the current study were to determine whether increased EF was associated with improved adiposity in children, and if this was due to differences in dietary and activity behaviors. Cross‐sectional data from 1,700 children aged 9–10 year were analyzed to examine the associations between EF, as estimated from diet diaries, measures of adiposity, and activity measured by accelerometer. Analyses were stratified by obesity status using waist‐to‐height ratio to define obesity as it has been shown to be a good predictor of adverse health outcomes. Mean EF was 4.3 occasions/day and after adjustment for underreporting, energy intake (EI), and activity significant relative mean differences of −2.4% for body weight (P = 0.001), −1.0% for BMI (P = 0.020), −33% for BMI z‐score (P = 0.014), and −0.6% for waist circumference (P = 0.031) per increase in eating occasion were found in healthy‐weight but not centrally obese children. Differences between the extreme quartiles of EF were observed for total fat intake at breakfast (−18%, P < 0.001), fruit and vegetables from snacks (201% healthy‐weight and 209% centrally obese children, P < 0.01), and for healthy‐weight children, vigorous activity (4%, P = 0.003). Increased EF was favorably associated with adiposity, diet quality, and activity behaviors in healthy‐weight but not centrally obese children. Future obesity interventions should consider the mediating role of diet quality and activity in the relationship between EF and adiposity in children.

Iron status in the elderly

Highlights • Iron-deficiency anaemia is relatively common in old age.• It is mainly caused by an inadequate diet and the presence of inflammation.• It leads to a decline in physical performance, increased risk of falling, and depression.• High dose iron supplements may have adverse effects.• Iron status is difficult to measure in elderly people and there are no universally agreed ‘cut-off’ values.

Dietary fibre, fluids and physical activity in relation to constipation symptoms in pre-adolescent children.

Children with constipation are advised frequently to increase their activity levels, fluids and fibre intake. The aim of this study was to examine the prevalence of constipation symptoms in a group of schoolchildren while concurrently assessing their activity levels and fluid and fibre intakes. Eighty-four pre-adolescent children aged 7—10 years were recruited. All children completed a bowel function diary, an activity diary and a weighed food inventory for seven consecutive days. Of the children, 33 percent were found to experience constipation symptoms. Fluid and fibre intakes were higher in the children who did not experience constipation symptoms, but the results were not significant. Physical activity levels were found to be significantly higher in the children reporting constipation symptoms, with the most active children reporting low water intakes. This study has highlighted that constipation symptoms are a prevalent problem in children not seeking medical treatment.

Food and drink consumption at school lunchtime: the impact of lunch type and contribution to overall intake in British 9–10-year-old children

OBJECTIVE To examine the differences in dietary intakes of children consuming school meals and packed lunches, the contribution of lunchtime intake to overall dietary intake, and how lunchtime intake relates to current food-based recommendations for school meals. DESIGN Cross-sectional analysis of overall intake of macronutrients and food choice from 4 d food diaries and school lunchtime intake from the two diary days completed while at school. SETTING Norfolk, UK. SUBJECTS One thousand six hundred and twenty-six children (aged 9-10 years) attending ninety Norfolk primary schools. RESULTS At school, lunchtime school meal eaters consumed more vegetables, sweet snacks, chips, starchy foods and milk, and less squash/cordial, fruit, bread, confectionery and savoury snacks than packed lunch eaters. These differences were also reflected in the overall diet. On average school meal eaters met the School Food Trust (SFT) food-based standards, while food choices among packed lunch eaters were less healthy. The contribution of food consumed at school lunchtime to overall diet varied by food and lunch type, ranging from 0.8 % (milk intake in packed lunches) to 74.4 % (savoury snack intake in packed lunches). CONCLUSIONS There were significant differences in the foods consumed by school meal and packed lunch eaters, with food choices among school meal eaters generally in line with SFT standards. The food choices made at school lunchtime make a significant contribution to overall diet.

Breakfast consumption and daily physical activity in 9–10-year-old British children

OBJECTIVE To examine the association between breakfast consumption and physical activity in a well-characterised sample of English children. DESIGN Cross-sectional study using food diaries to record breakfast consumption and accelerometry to assess physical activity. SETTING Norfolk county, England. SUBJECTS Children (n 1697) aged 9–10 years from the SPEEDY (Sport, Physical Activity and Eating behaviour: Environmental Determinants in Young people) study. RESULTS Boyswho consumed a poor-quality breakfast based on dairy product, cereal and fruit intakes spent approximately 7 min more time in moderate-to-vigorous physical activity (MVPA) during weekday afternoons and evenings compared with those who did not consume breakfast (P,0?05). On weekend days, boys who consumed a poor- or good-quality breakfast spent approximately 6 and 5min less time respectively being sedentary during the mornings compared with breakfast nonconsumers (P,0?05). Boys who consumed a good-quality breakfast spent almost 3min more in MVPA during the morning on weekend days compared with nonconsumers, and boys who consumed a poor- or good-quality breakfast were 22% and 16% more active overall respectively than breakfast non-consumers (P,0?05). During the rest of the day, boys who consumed a good-quality breakfast spent about 11 min less time being sedentary (P,0?05) and 7minmore time in MVPA (P,0?01). CONCLUSIONS Although some associations between breakfast consumption and physical activity were detected for boys, the present study does not provide strong evidence that failing to consume breakfast, or having a low energy intake at breakfast time, is detrimental to children’s physical activity levels.

Characterizing blood metabolomics profiles associated with self-reported food intakes in female twins

Using dietary biomarkers in nutritional epidemiological studies may better capture exposure and improve the level at which diet-disease associations can be established and explored. Here, we aimed to identify and evaluate reproducibility of novel biomarkers of reported habitual food intake using targeted and non-targeted metabolomic blood profiling in a large twin cohort. Reported intakes of 71 food groups, determined by FFQ, were assessed against 601 fasting blood metabolites in over 3500 adult female twins from the TwinsUK cohort. For each metabolite, linear regression analysis was undertaken in the discovery group (excluding MZ twin pairs discordant [≥1 SD apart] for food group intake) with each food group as a predictor adjusting for age, batch effects, BMI, family relatedness and multiple testing (1.17x10-6 = 0.05/[71 food groups x 601 detected metabolites]). Significant results were then replicated (non-targeted: P<0.05; targeted: same direction) in the MZ discordant twin group and results from both analyses meta-analyzed. We identified and replicated 180 significant associations with 39 food groups (P<1.17x10-6), overall consisting of 106 different metabolites (74 known and 32 unknown), including 73 novel associations. In particular we identified trans-4-hydroxyproline as a potential marker of red meat intake (0.075[0.009]; P = 1.08x10-17), ergothioneine as a marker of mushroom consumption (0.181[0.019]; P = 5.93x10-22), and three potential markers of fruit consumption (top association: apple and pears): including metabolites derived from gut bacterial transformation of phenolic compounds, 3-phenylpropionate (0.024[0.004]; P = 1.24x10-8) and indolepropionate (0.026[0.004]; P = 2.39x10-9), and threitol (0.033[0.003]; P = 1.69x10-21). With the largest nutritional metabolomics dataset to date, we have identified 73 novel candidate biomarkers of food intake for potential use in nutritional epidemiological studies. We compiled our findings into the DietMetab database (http://www.twinsuk.ac.uk/dietmetab-data/), an online tool to investigate our top associations.

The relationship between dietary magnesium intake, stroke and its major risk factors, blood pressure and cholesterol, in the EPIC-Norfolk cohort

BACKGROUND Dietary magnesium could modify the major stroke risk factors, high blood pressure (BP) and cholesterol, but has been understudied in both sexes in a single population. This study aimed to investigate if dietary magnesium intake was associated with BP, total cholesterol (TC) and incident stroke risk in an adult population. METHODS We conducted cross-sectional analyses in a case-cohort study of 4443, men and women aged 40-75, representative of 25,639 participants years of the EPIC (European Prospective Investigation into Cancer)-Norfolk cohort. The cohort included 928 stroke cases (42,556.5 person years). Dietary data from 7 day food diaries were analysed using multivariate regression to assess associations between quintiles or data-derived categories of dietary magnesium intake and BP, TC and stroke risk, adjusted for relevant confounders. RESULTS We observed differences of -7 mmHg systolic BP (P trend ≤ 0.01) and -3.8 mmHg diastolic BP (P trend=0.01) between extreme intakes of magnesium in men, a significant inverse association with TC was observed (P trend=0.02 men and 0.04 women). Compared to the bottom 10%, the top 30% of magnesium intake was associated with a 41% relative reduction in stroke risk (HR 0.59; 95% CI 0.38-0.93) in men. CONCLUSIONS Lower dietary magnesium intake was associated with higher BP and stroke risk, which may have implications for primary prevention.