Vitamin D deficiency has been implicated in the aetiology of infectious diseases and metabolic syndrome. These diseases are prevalent in the African and Asian-Indian populations of South Africa; however, there is limited data on 25-hydroxyvitamin D (25(OH)D) concentrations in these populations. The aim of the present study was to assess the vitamin D status and its predictors in healthy adults in Johannesburg. We assessed the vitamin D status of 730 adult African and Asian-Indian subjects residing in Johannesburg. The contributions of sun exposure, season, dietary intake of Ca and vitamin D, total body fat and body fat distribution to 25(OH)D concentrations were assessed. The concentrations of 25(OH)D were measured by HPLC. The contribution of 25(OH)D3 to total 25(OH)D concentrations was assessed. The mean age of the subjects was 42·6 (sd 13·1) years (range: 18–65). Concentrations of 25(OH)D < 30 nmol/l were found in 28·6 % of the Asian-Indian subjects in comparison with 5·1 % of the African subjects (P< 0·0001). Parathyroid hormone (PTH) concentrations were negatively associated with 25(OH)D concentrations, while season and sun exposure were positive predictors explaining 16 % of the variance in 25(OH)D concentrations (P< 0·0001) in the African subjects. In the Asian-Indian subjects, PTH concentrations were negatively associated with 25(OH)D concentrations, while male sex, season and Ca supplementation were positive predictors and explained 17 % of the variance in 25(OH)D concentrations (P< 0·0001). In the multivariate regression analysis, neither total body fat nor body fat distribution was predictive of 25(OH)D concentrations in either group. In conclusion, factors such as sun exposure, dietary supplement use and ethnicity are important determinants of plasma 25(OH)D concentrations.

A number of studies have demonstrated that consuming almonds increases satiety but does not result in weight gain, despite their high energy and lipid content. To understand the mechanism of almond digestion, in the present study, we investigated the bioaccessibility of lipids from masticated almonds during in vitro simulated human digestion, and determined the associated changes in cell-wall composition and cellular microstructure. The influence of processing on lipid release was assessed by using natural raw almonds (NA) and roasted almonds (RA). Masticated samples from four healthy adults (two females, two males) were exposed to a dynamic gastric model of digestion followed by simulated duodenal digestion. Between 7·8 and 11·1 % of the total lipid was released as a result of mastication, with no significant differences between the NA and RA samples. Significant digestion occurred during the in vitro gastric phase (16·4 and 15·9 %) and the in vitro duodenal phase (32·2 and 32·7 %) for the NA and RA samples, respectively. Roasting produced a smaller average particle size distribution post-mastication; however, this was not significant in terms of lipid release. Light microscopy showed major changes that occurred in the distribution of lipid in all cells after the roasting process. Further changes were observed in the surface cells of almond fragments and in fractured cells after exposure to the duodenal environment. Almond cell walls prevented lipid release from intact cells, providing a mechanism for incomplete nutrient absorption in the gut. The composition of almond cell walls was not affected by processing or simulated digestion.

Despite the importance of skeletal growth during adolescence, there is limited research reporting vitamin D status and its predictors in adolescents. Using prospective data from the Western Australian Pregnancy Cohort (Raine) Study, we investigated vitamin D status and predictors of serum 25-hydroxyvitamin D (25(OH)D) concentrations in adolescents. Serum 25(OH)D concentrations were measured in the same participants at 14 and 17 years (n 1045 at both time points). The percentage of adolescents with serum 25(OH)D concentrations < 50, 50–74·9 and ≥ 75 nmol/l was reported year-round and by month of blood collection. We examined the predictors of serum 25(OH)D concentrations, including sex, race, month of blood collection, physical activity, BMI, family income, and Ca and vitamin D intakes (n 919 at 14 years; n 570 at 17 years), using a general linear mixed model. At 14 years, 31 % of adolescents had serum 25(OH)D concentrations between 50 and 74·9 nmol/l and a further 4 % had concentrations < 50 nmol/l. At 17 years, 40 % of adolescents had serum 25(OH)D concentrations between 50 and 74·9 nmol/l and 12 % had concentrations < 50 nmol/l. Caucasian ethnicity, being sampled at the end of summer, exercising more, having a lower BMI, a higher Ca intake and a higher family income were significantly associated with higher serum 25(OH)D concentrations. The proportion of adolescents with serum 25(OH)D concentrations < 50 nmol/l was low in this Western Australian cohort. There is a need for international consensus on defining adequate vitamin D status in order to determine whether strategies to increase vitamin D status in adolescents are warranted.

In the present study, salmon products available from UK retailers were analysed to determine the levels of n-3 long-chain PUFA (LC-PUFA), a key determinant of nutritional quality. There was a wide variation in the proportions and absolute contents of EPA and DHA in the products. Relatively high contents of 18 : 1n-9, 18 : 2n-6 and 18 : 3n-3, characteristic of vegetable oils (VO), were found in several farmed salmon products, which also had generally lower proportions of EPA and DHA. In contrast, farmed salmon products with higher levels of 16 : 0 and 22 : 1, characteristic of fish oil (FO), had higher proportions of EPA and DHA. Therefore, there was a clear correlation between the levels of VO and FO in feeds and the proportions of n-3 LC-PUFA in products. Although wild salmon products were characterised by higher proportions of n-3 LC-PUFA (20–40 %) compared with farmed fish (9–26 %), they contained lower total lipid contents (1–6 % compared with 7–17 % in farmed salmon products). As a result, farmed salmon products invariably had higher levels of n-3 LC-PUFA in absolute terms (g/100 g fillet) and, therefore, delivered a higher ‘dose’ of EPA and DHA per portion. Overall, despite the finite and limiting supply of FO and increasing use of VO, farmed salmon continue to be an excellent source of and delivery system for n-3 LC-PUFA to consumers.

Lactobacilli are indigenous microbes of the stomach of rodents, with much lower numbers being present in mice fed a purified diet than in those fed a non-purified diet. We postulated that gastric emptying (GE) is responsible for the different colonisation levels of lactobacilli and tested this hypothesis in the present study. BALB/cCr Slc mice were fed either a non-purified diet or a purified diet for 2 weeks. The number of gastric tissue-associated lactobacilli was lower in mice fed the purified diet than in those fed the non-purified diet. GE, estimated by measuring the food recovered from the stomach, was higher in mice fed the purified diet than in those fed the non-purified diet and correlated negatively with the number of lactobacilli. Mice fed the non-purified diet exhibited lower GE rates even when lactobacilli were eliminated by ampicillin administration through the drinking-water, suggesting that GE is the cause but not the consequence of different Lactobacillus colonisation levels. The plasma concentrations of acylated ghrelin, a gastric hormone that promotes GE, were higher in mice fed the purified diet than in those fed the non-purified diet. There was a negative correlation between GE and the number of lactobacilli in mice fed the non-purified diet, the purified diet, and the purified diet supplemented with sugarbeet fibre (200 g/kg diet) or carboxymethyl cellulose (40 g/kg diet). We propose that a higher GE rate contributes, at least in part, to lower gastric colonisation levels of lactobacilli in mice fed a purified diet.

Consumption of a Mediterranean diet (MD) and genetic variation in the glucokinase regulatory protein (GCKR) gene have been reported to be associated with TAG and glucose metabolism. It is uncertain whether there is any interaction between these factors. Therefore, the aims of the present study were to test the association of adherence to a MD and rs780094 (G>A) SNP in the GCKR gene with the markers of cardiometabolic risk, and to investigate the interaction between genetic variation and MD adherence. We studied 20 986 individuals from the European Prospective Investigation into Cancer (EPIC)-Norfolk study. The relative Mediterranean Diet Score (rMED: range 0–18) was used to assess MD adherence. Linear regression was used to estimate the association between the rMED, genotype and cardiometabolic continuous traits, adjusting for potential confounders. In adjusted analyses, we observed independent associations of MD adherence and genotype with cardiometabolic risk, with the highest risk group (AA genotype; lowest rMED) having higher concentrations of TAG, total cholesterol and apoB (12·5, 2·3 and 3·1 %, respectively) v. those at the lowest risk (GG genotype; highest rMED). However, the associations of MD adherence with metabolic markers did not differ by genotype, with no significant gene–diet interactions for lipids or for glycated Hb. In conclusion, we found independent associations of the rMED and of the GCKR genotype with cardiometabolic profile, but found no evidence of interaction between them.

Diets with a high glycaemic index (GI) or glycaemic load (GL) have been hypothesised to increase the risk of diabetes, CVD and some cancers. In the present study, the associations of dietary GI and GL with the risk of all-cause and cause-specific mortality were prospectively examined in a general population in Japan, where white rice is the main contributor of dietary GI and GL. A total of 28 356 residents of Takayama City, Japan, who responded to a self-administered questionnaire in 1992 were included in the present analyses. Dietary intake was assessed using a validated FFQ. Mortality was ascertained over 16 years. In men, dietary GI was found to be significantly inversely associated with the risk of all-cause and non-cancer, non-cardiovascular mortality; the hazard ratios (HR) for the highest v. lowest quartile were 0·80 (95 % CI 0·68, 0·95) and 0·64 (95 % CI 0·49, 0·84), respectively. Dietary GL was found to be significantly inversely associated with the risk of all-cause, cancer, and non-cancer, non-cardiovascular mortality; the HR for the highest v. lowest quartile were 0·71 (95 % CI 0·59, 0·86), 0·71 (95 % CI 0·52, 0·99) and 0·64 (95 % CI 0·48, 0·87), respectively. The results obtained for the GL derived from white rice, but not from other foods, closely mirrored those obtained for overall GL. In women, dietary GI was found to be significantly positively associated with the risk of cardiovascular mortality; the HR for the highest v. lowest quartile was 1·56 (95 % CI 1·15, 2·13). The results of the present study suggest potential favourable effects of dietary GI and GL on mortality in men, but an association between high GI and an increased risk of cardiovascular mortality in women.

Findings from research that has assessed the influence of dietary factors on child obesity have been equivocal. In the present study, we aimed to test the hypothesis that a positive change in diet quality is associated with favourable changes in BMI z-scores (zBMI) in schoolchildren from low socio-economic backgrounds and to examine whether this effect is modified by BMI category at baseline. The present study utilised data from a subsample (n 216) of the Resilience for Eating and Activity Despite Inequality study, a longitudinal cohort study with data collected in 2007–8 (T1) and 2010–11 (T2) in socio-economically disadvantaged women and children (5–12 years at T1). Dietary data were collected using a FFQ and diet quality index (DQI) scores derived at both time points. The objective measures of weight, height and physical activity (accelerometers) were included. The other variables were reported in the questionnaires. We examined the association between change in DQI and change in zBMI, using linear regression analyses adjusted for physical activity, screen sedentary behaviour and maternal education level both in the whole sample and in the sample stratified by overweight status at baseline. After accounting for potential covariates, change in diet quality was found to be inversely associated with change in zBMI only in children who were overweight at baseline (P= 0·035), thus supporting the hypothesis that improvement in diet quality is associated with a concurrent improvement in zBMI among already overweight children, but not among those with a normal BMI status. The identification of modifiable behaviours such as diet quality that affect zBMI longitudinally is valuable to inform future weight gain prevention interventions in vulnerable groups.

The present study examined whether exposure to vitamin D from fortified margarine and milk during prenatal life influenced mean birth weight and the risk of high or low birth weight. The study was based on the Danish vitamin D fortification programme, which was a societal intervention with mandatory fortification of margarine during 1961–1985 and voluntary fortification of low-fat milk between 1972 and 1976. The influence of prenatal vitamin D exposure on birth weight was investigated among 51 883 Danish children, by comparing birth weight among individuals born during 2 years before or after the initiation and termination of vitamin D fortification programmes. In total, four sets of analyses were performed. Information on birth weight was available in the Copenhagen School Health Record Register for all school children in Copenhagen. The mean birth weight was lower among the exposed than non-exposed children during all study periods (milk initiation − 20·3 (95 % CI − 39·2, − 1·4) g; milk termination − 25·9 (95 % CI − 46·0, − 5·7) g; margarine termination − 45·7 (95 % CI − 66·6, − 24·8) g), except during the period around the initiation of margarine fortification, where exposed children were heavier than non-exposed children (margarine initiation 27·4 (95 % CI 10·8, 44·0) g). No differences in the odds of high (>4000 g) or low ( < 2500 g) birth weight were observed between the children exposed and non-exposed to vitamin D fortification prenatally. Prenatal exposure to vitamin D from fortified margarine and milk altered birth weight, but the effect was small and inconsistent, reaching the conclusion that vitamin D fortification seems to be clinically irrelevant in relation to fetal growth.

Diet is related to many chronic disease conditions such as the metabolic syndrome (MetS). We set out to compare behaviour-related with disease-related patterns and their association with the MetS in a German cross-sectional study. A total of 905 participants of a Northern German cohort (aged 25–82 years) completed a FFQ, underwent anthropometric assessments and provided a blood sample. Dietary patterns were derived by principal component analysis (PCA) and reduced-rank regression (RRR) from forty-two food groups. Components of the MetS were used as response variables for the RRR analysis. Simplified patterns comprising ten food groups were generated. Logistic regression analysis was performed to evaluate the likelihood of having the MetS across the quartiles of simplified pattern scores. We identified two similar dietary patterns derived by PCA and RRR characterised by high intakes of potatoes, various vegetables, red and processed meat, fats, sauce and bouillon. Comparing simplified patterns, an increased RRR pattern score was associated with a higher OR (2·18, 95 % CI 1·25, 3·81) of having the MetS than an increased PCA pattern score (OR 1·92, 95 % CI 1·21, 3·03). Comparing concordant food groups by both dietary pattern methods, a diet high in legumes, beef, processed meat and bouillon was also positively associated with the prevalence of the MetS after adjustment for potential confounders (OR 1·71, 95 % CI 1·04, 2·79). We identified a behaviour-related pattern that was positively associated with the MetS. The application of both dietary pattern methods may be advantageous to obtain information for designing and realising dietary guidelines. Prospective studies are needed to confirm the results.

Nutrient profiling systems are powerful tools for public health initiatives, as they aim at categorising foods according to their nutritional quality. The British Food Standards Agency (FSA) nutrient profiling system (FSA score) has been validated in a British food database, but the application of the model in other contexts has not yet been evaluated. The objective of the present study was to assess the application of the British FSA score in a French food composition database. Foods from the French NutriNet-Santé study food composition table were categorised according to their FSA score using the Office of Communication (OfCom) cut-off value (‘healthier’ ≤ 4 for foods and ≤ 1 for beverages; ‘less healthy’ >4 for foods and >1 for beverages) and distribution cut-offs (quintiles for foods, quartiles for beverages). Foods were also categorised according to the food groups used for the French Programme National Nutrition Santé (PNNS) recommendations. Foods were weighted according to their relative consumption in a sample drawn from the NutriNet-Santé study (n 4225), representative of the French population. Classification of foods according to the OfCom cut-offs was consistent with food groups described in the PNNS: 97·8 % of fruit and vegetables, 90·4 % of cereals and potatoes and only 3·8 % of sugary snacks were considered as ‘healthier’. Moreover, variability in the FSA score allowed for a discrimination between subcategories in the same food group, confirming the possibility of using the FSA score as a multiple category system, for example as a basis for front-of-pack nutrition labelling. Application of the FSA score in the French context would adequately complement current public health recommendations.

Although epidemiological findings support a role for vitamin K status in the improvement of bone indices in adult patients with Crohn's disease (CD), this needs to be confirmed in double-blind, randomised controlled trials (RCT) with phylloquinone (vitamin K1). By conducting two RCT, the present study aimed to first establish whether supplementation with 1000 μg of phylloquinone daily near-maximally suppresses the percentage of undercarboxylated osteocalcin in serum (%ucOC; marker of vitamin K status) in adult patients with CD currently in remission as it does in healthy adults and second determine the effect of supplementation with phylloquinone at this dose for 12 months on the indices of bone turnover and bone mass. The initial dose-ranging RCT was conducted in adult patients with CD (n 10 per group) using 0 (placebo), 1000 or 2000 μg of phylloquinone daily for 2 weeks. In the main RCT, the effect of placebo v. 1000 μg vitamin K/d (both co-administered with Ca (500 mg/d) and vitamin D3 (10 μg/d)) for 12 months (n 43 per group) on the biochemical indices of bone turnover (determined by enzyme immunoassay) and bone mass (determined by dual-energy X-ray absorptiometry) were investigated. At baseline, the mean %ucOC was 47 %, and this was suppressed upon supplementation with 1000 μg of phylloquinone daily ( − 81 %; P< 0·01) and not suppressed further by 2000 μg of phylloquinone daily. Compared with the placebo, supplementation with 1000 μg of phylloquinone daily for 12 months had no significant effect (P>0·1) on bone turnover markers or on the bone mass of the lumbar spine or femur, but modestly increased (P< 0·05) the bone mass of the total radius. Despite near maximal suppression of serum %ucOC, supplementation with 1000 μg of phylloquinone daily (with Ca and vitamin D3) had no effect on the indices of bone health in adult CD patients with likely vitamin K insufficiency.

Diet composition may affect blood pressure (BP), but the mechanisms are unclear. The aim of the present study was to compare postprandial BP-related responses to the ingestion of pea protein, milk protein and egg-white protein. In addition, postprandial BP-related responses to the ingestion of maltodextrin were compared with those to the ingestion of sucrose and a protein mix. We hypothesised that lower postprandial total peripheral resistance (TPR) and BP levels would be accompanied by higher plasma concentrations of nitric oxide, insulin, glucagon-like peptide 1 (GLP-1) and glucagon. On separate occasions, six meals were tested in a randomised order in forty-eight overweight or obese adults with untreated elevated BP. Postprandial responses of TPR, BP and plasma concentrations of insulin, glucagon, GLP-1 and nitrite, nitroso compounds (RXNO) and S-nitrosothiols (NOx) were measured for 4 h. No differences were observed in TPR responses. Postprandial BP levels were higher after the ingestion of the egg-white-protein meal than after that of meals containing the other two proteins (P≤ 0·01). The ingestion of the pea-protein meal induced the highest NOx response (P≤ 0·006). Insulin and glucagon concentrations were lowest after the ingestion of the egg-white-protein meal (P≤ 0·009). Postprandial BP levels were lower after the ingestion of the maltodextrin meal than after that of the protein mix and sucrose meals (P≤ 0·004), while postprandial insulin concentrations were higher after the ingestion of the maltodextrin meal than after that of the sucrose and protein mix meals after 1–2 h (P≤ 0·0001). Postprandial NOx, GLP-1 and glucagon concentrations were lower after the ingestion of the maltodextrin meal than after that of the protein mix meal (P≤ 0·008). In conclusion, different protein and carbohydrate sources induce different postprandial BP-related responses, which may be important for BP management. Lower postprandial BP levels are not necessarily accompanied by higher NOx, insulin, glucagon or GLP-1 responses.

The main objective of the present study was to examine the association between dietary Fe intake and dietary predictors of Fe status and Hb concentration among lactating women in Bhaktapur, Nepal. We included 500 randomly selected lactating women in a cross-sectional survey. Dietary information was obtained through three interactive 24 h recall interviews including personal recipes. Concentrations of Hb and plasma ferritin and soluble transferrin receptors were measured. The daily median Fe intake from food was 17·5 mg, and 70 % of the women were found to be at the risk of inadequate dietary Fe intake. Approximately 90 % of the women had taken Fe supplements in pregnancy. The prevalence of anaemia was 20 % (Hb levels < 123 g/l) and that of Fe deficiency was 5 % (plasma ferritin levels < 15 μg/l). In multiple regression analyses, there was a weak positive association between dietary Fe intake and body Fe (β 0·03, 95 % CI 0·014, 0·045). Among the women with children aged < 6 months, but not those with older infants, intake of Fe supplements in pregnancy for at least 6 months was positively associated with body Fe (P for interaction < 0·01). Due to a relatively high dietary intake of non-haem Fe combined with low bioavailability, a high proportion of the women in the present study were at the risk of inadequate intake of Fe. The low prevalence of anaemia and Fe deficiency may be explained by the majority of the women consuming Fe supplements in pregnancy.

Maternal nutritional status during pregnancy has been reported to be associated with childhood asthma and atopic disease. The Avon Longitudinal Study of Parents and Children has reported associations between reduced umbilical cord Fe status and childhood wheeze and eczema; however, follow-up was short and lung function was not measured. In the present study, the associations between maternal Fe status during pregnancy and childhood outcomes in the first 10 years of life were investigated in a subgroup of 157 mother–child pairs from a birth cohort with complete maternal, fetal ultrasound, blood and child follow-up data. Maternal Fe intake was assessed using FFQ at 32 weeks of gestation and Hb concentrations and serum Fe status (ferritin, soluble transferrin receptor and TfR-F (transferrin receptor:ferritin) index) were measured at 11 weeks of gestation and at delivery. Maternal Fe intake, Hb concentrations and serum Fe status were found to be not associated with fetal or birth measurements. Unit increases in first-trimester maternal serum TfR concentrations (OR 1·44, 95 % CI 1·05, 1·99) and TfR-F index (OR 1·42, 95 % CI 1·10, 1·82) (i.e. decreasing Fe status) were found to be associated with an increased risk of wheeze, while unit increases in serum ferritin concentrations (i.e. increasing Fe status) were found to be associated with increases in standardised mean peak expiratory flow (PEF) (β 0·25, 95 % CI 0·09, 0·42) and forced expiratory volume in the first second (FEV1) (β 0·20, 95 % CI 0·08, 0·32) up to 10 years of age. Increasing maternal serum TfR-F index at delivery was found to be associated with an increased risk of atopic sensitisation (OR 1·35, 95 % CI 1·02, 1·79). The results of the present study suggest that reduced maternal Fe status during pregnancy is adversely associated with childhood wheeze, lung function and atopic sensitisation, justifying further studies on maternal Fe status and childhood asthma and atopic disease.

The present narrative review compares evidence from experimental, epidemiological and clinical studies of the health benefits of rapeseed oil (RO) (known as canola oil) and olive oil (OO) in order to assess whether rapeseed oil is suitable as a sustainable alternative to OO as part of a Mediterranean-style diet in countries where olive trees do not grow. From epidemiological studies, the evidence for cardiovascular protection afforded by extra-virgin OO is ‘convincing’, and for cancers ‘limited-suggestive’, especially oestrogen receptor-negative breast cancer, but more studies are required in relation to cognitive impairment. Evidence for RO is limited to short-term studies on the biomarkers of risk factors for CVD. Any benefits of RO are likely to be due to α-linolenic acid; however, it is prone to oxidation during frying. We conclude that due to a lack of evidence from observational or intervention studies indicating that RO has comparable health benefits to extra-virgin OO, RO cannot currently be recommended as a suitable substitute for extra-virgin OO as part of a Mediterranean-style diet.

The effect of high-grain (HG) feeding on caecal bacterial microbiota composition and fermentation and mucosa health is largely unknown. In the present study, ten male goats were randomly assigned to either a group fed a hay diet (0 % grain; n 5) or a group fed a HG diet (65 % grain; n 5) to characterise the changes in the composition of the bacterial community and mucosal morphology in the caecum. After 7 weeks of feeding, the HG diet decreased the caecal pH (P< 0·001) and increased (P< 0·001 to P< 0·004) the caecal digesta concentrations of total volatile fatty acids and lipopolysaccharide (LPS). Pyrosequencing of the 16S ribosomal RNA gene revealed that HG feeding increased (P= 0·001 to P= 0·009) the abundance of predominant genera Turicibacter and Clostridium in the caecal lumen and in the caecal mucosa and decreased (P< 0·001 to P< 0·009) the proportion of Bacteroides in the lumen and Mucispirillum in the mucosa compared with the hay diet. Furthermore, the HG diet-fed goats exhibited intense epithelial damage and up-regulation (P< 0·001 to P< 0·025) of the relative mRNA expression of IL-1β, IL-6, IL-12 and interferon-γ (IFN-γ) in the caecal mucosa. The correlation analysis revealed that alterations in caecal pH, LPS concentration and mucosa-associated microbiota abundance during HG feeding might partly contribute to local inflammation. Collectively, these results provide insight into the adaptive response of caecal bacterial populations to HG feeding in goats and reveal that the fermentable substrates that flow into the caecum may cause dramatic alterations in microbial compositions and play a significant role in caecal dysfunction.

Intakes of saturated fat (SF) and dietary fibre, body mass and physical activity are all associated with the incidence of type 2 diabetes mellitus. Their relative importance for the maintenance of normal glucose metabolism is not fully known. In a population-based sample of 1114 individuals, aged 58–78 years, dietary intakes were assessed by 4 d food records and cardiorespiratory fitness as maximal oxygen uptake. Insulin secretion, insulin sensitivity, the early-phase disposition index (DI30) and the total disposition index (DI120) were assessed based on an oral glucose tolerance test. Linear associations were modelled using linear regression. Combined effects were studied by introducing SF and fibre intakes, as well as cardiorespiratory fitness and waist circumference (WC) as dichotomised variables in general linear models. Intakes of dietary fibre and whole-grain bread were positively associated with insulin sensitivity, independent of physical fitness and WC. In women, dietary fibre intake was also positively associated with DI30. The negative association of high WC with DI30 was attenuated by a combination of low SF intake and high cardiorespiratory fitness. In conclusion, dietary fibre and a combination of low SF intake and high cardiorespiratory fitness may contribute to the maintenance of normal glucose metabolism, independent of WC.

Few studies have investigated the relative validity of FFQ in young children and no study has investigated the relative validity of changes in children's food intake in a longitudinal context. The aim of the present study was to compare the FFQ of the longitudinal Family Influences on Food Intake study, assessing children's food intake in the previous 3 months, with a 3 d online food record when children were 3 and 7 years old, as well as to investigate the relative validity of changes in food group intake over a 4-year period. Parents (n 89) completed the FFQ and an online food record over three non-consecutive days on two separate occasions (January–April 2008 and 2012). Wilcoxon signed-rank tests and Spearman's correlations were used to compare food group intake and changes in intake assessed using both methods. In 2008, the intake of eleven of the twenty-two food groups was overestimated and that of four food groups underestimated in the FFQ in comparison with the online tool; in 2012, the intake of four food groups was overestimated and that of seven food groups underestimated. Nevertheless, changes in intake did not differ significantly between the two methods for eighteen food groups. Correlations in 2008 and 2012 were, on average, 0·47; correlations between the changes in dietary intake were, on average, 0·26. The results suggest that despite the significant differences between the two methods for a number of food groups at both baseline and/or follow-up, the FFQ can be used to monitor changes in dietary intake for groups of young children.

Given the high intake levels of soya and low incidence rates of breast cancer in Asian countries, isoflavones, substances with an oestrogen-like structure occurring principally in soyabeans, are postulated to be cancer protective. In the present study, we examined the association of dietary isoflavone intake with breast cancer risk in 84 450 women (896 in situ and 3873 invasive cases) who were part of the Multiethnic Cohort (Japanese Americans, whites, Latinos, African Americans and Native Hawaiians) with a wide range of soya intake levels. The absolute levels of dietary isoflavone intake estimated from a baseline FFQ were categorised into quartiles, with the highest quartile being further subdivided to assess high dietary intake. The respective intake values for the quartiles (Q1, Q2, Q3, and lower and upper Q4) were 0– < 3·2, 3·2– < 6·7, 6·7– < 12·9, 12·9– < 20·3, and 20·3–178·7 mg/d. After a mean follow-up period of 13 years, hazard ratios (HR) and 95 % CI were calculated using Cox regression models stratified by age and adjusted for known confounders. Linear trends were tested by modelling continuous variables of interest assigned the median value within the corresponding quartile. No statistically significant association was observed between dietary isoflavone intake and overall breast cancer risk (HR for upper Q4 v. Q1: 0·96 (95 % CI 0·85, 1·08); P trend = 0·40). While the test for interaction was not significant (P= 0·14), stratified analyses suggested possible ethnic/racial differences in risk estimates, indicating that higher isoflavone intakes may be protective in Latina, African American and Japanese American women. These results are in agreement with those of previous meta-analyses showing no protection of isoflavones at low intake levels, but suggesting inverse associations in populations consuming high amounts of soya.