Flaxseed is the richest source of the lignan secoisolariciresinol diglucoside (SDG). After ingestion, SDG is converted to secoisolariciresinol, which is further metabolised to the mammalian lignans enterodiol and enterolactone. A growing body of evidence suggests that SDG metabolites may provide health benefits due to their weak oestrogenic or anti-oestrogenic effects, antioxidant activity, ability to induce phase 2 proteins and/or inhibit the activity of certain enzymes, or by mechanisms yet unidentified. Human and animal studies identify the benefits of SDG consumption. SDG metabolites may protect against CVD and the metabolic syndrome by reducing lipid and glucose concentrations, lowering blood pressure, and decreasing oxidative stress and inflammation. Flax lignans may also reduce cancer risk by preventing pre-cancerous cellular changes and by reducing angiogenesis and metastasis. Thus, dietary SDG has the potential to decrease the incidence of several chronic diseases that result in significant morbidity and mortality in industrialised countries. The available literature, though, makes it difficult to clearly identify SDG health effects because of the wide variability in study methods. However, the current evidence suggests that a dose of at least 500 mg SDG/d for approximately 8 weeks is needed to observe positive effects on cardiovascular risk factors in human patients. Flaxseed and its lignan extracts appear to be safe for most adult populations, though animal studies suggest that pregnant women should limit their exposure. The present review discusses the potential health benefits of SDG in humans, with supporting evidence from animal studies, and offers suggestions for future research.

Consumption of simple carbohydrates has markedly increased over the past decades, and may be involved in the increased prevalence in metabolic diseases. Whether an increased intake of fructose is specifically related to a dysregulation of glucose and lipid metabolism remains controversial. We therefore compared the effects of hypercaloric diets enriched with fructose (HFrD) or glucose (HGlcD) in healthy men. Eleven subjects were studied in a randomised order after 7 d of the following diets: (1) weight maintenance, control diet; (2) HFrD (3·5 g fructose/kg fat-free mass (ffm) per d, +35 % energy intake); (3) HGlcD (3·5 g glucose/kg ffm per d, +35 % energy intake). Fasting hepatic glucose output (HGO) was measured with 6,6-2H2-glucose. Intrahepatocellular lipids (IHCL) and intramyocellular lipids (IMCL) were measured by 1H magnetic resonance spectroscopy. Both fructose and glucose increased fasting VLDL-TAG (HFrD: +59 %, P < 0·05; HGlcD: +31 %, P = 0·11) and IHCL (HFrD: +52 %, P < 0·05; HGlcD: +58 %, P = 0·06). HGO increased after both diets (HFrD: +5 %, P < 0·05; HGlcD: +5 %, P = 0·05). No change was observed in fasting glycaemia, insulin and alanine aminotransferase concentrations. IMCL increased significantly only after the HGlcD (HFrD: +24 %, NS; HGlcD: +59 %, P < 0·05). IHCL and VLDL-TAG were not different between hypercaloric HFrD and HGlcD, but were increased compared to values observed with a weight maintenance diet. However, glucose led to a higher increase in IMCL than fructose.

Among procyanidins (PC), monomers, such as catechin and epicatechin, have been widely studied, whereas dimer and trimer oligomers have received much less attention, despite their abundance in our diet. Recent studies have showed that as dimers and trimers could be important in determining the biological effects of procyanidin-rich food, understanding their bioavailability and metabolism is fundamental. The purpose of the present work is to study the stability of PC under digestion conditions, the metabolism and the bioavailability by using a combination of in vitro and in vivo models. Simultaneously, the matrix effect of a carbohydrate-rich food on the digestibility and bioavailability of PC is investigated. The results show a high level of stability of PC under gastric and duodenal digestion conditions. However, the pharmacokinetic study revealed limited absorption. Free forms of dimers and trimers have been detected in rat plasma, reaching the maximum concentration 1 h after oral intake of a grape seed extract.

Adipocyte differentiation is probably controlled by transcriptional and post-transcriptional regulation. Longissimus lumborum from Angus steers (aged 155 d; seven animals per diet) fed high-starch or low-starch diets for 112 d (growing phase) followed by a common high-starch diet for an additional 112 d (finishing phase) was biopsied at 0, 56, 112 and 224 d for transcript profiling via quantitative PCR of twenty genes associated with adipogenesis and energy metabolism. At 56 d steers fed high starch had greater expression of PPARγ as well as the lipogenic enzymes ATP citrate lyase (ACLY), glucose-6-phosphate dehydrogenase (G6PD), fatty acid synthase (FASN), fatty acid binding protein 4 (FABP4), stearoyl-CoA desaturase (SCD), glycerol-3-phosphate acyltransferase, mitochondrial (GPAM), and diacylglycerol O-acyltransferase homologue 2 (DGAT2), and the adipokine adiponectin (ADIPOQ). Expression of insulin-induced gene 1 (INSIG1) was also greater with high starch at 56 d. Steers fed low starch experienced a marked increase in FASN, FABP4, SCD, DGAT2 and thyroid hormone-responsive (SPOT14 homologue, rat) (THRSP) between 56 and 112 d of feeding. A greater expression of the transcription factors sterol regulatory element-binding transcription factor 1 (SREBF1) and MLX interacting protein-like (MLXIPL) was observed at 224 d in steers fed high starch, suggesting a nutritional imprinting effect. Carryover effects of low starch feeding were discerned by greater expression at 224 d of THRSP, FABP4, SCD and DGAT2. These steers also had greater PPARγ at 224 d. Despite these responses, low starch led to greater expression at 224 d of nuclear receptor subfamily 2, group F, member 2 (NR2F2), a known repressor of rodent adipocyte differentiation through its negative effects on PPARγ, ADIPOQ and FABP4. Results suggested that early exposure to high starch induced precocious intramuscular adipocyte proliferation and metabolic imprinting of lipogenic transcription regulators. Low starch might have blunted the PPARγ-driven adipogenic response through up-regulation of NR2F2 but the endogenous ligand for this nuclear receptor remains unknown.

The impact of excess dietary leucine (Leu) was studied in two growth assays with pigs (8–25 kg). In each trial, forty-eight pigs were allotted to one of six dietary groups. The dietary Leu supply increased from treatment L100 to L200 (three increments). To guarantee that interactions between the branched-chain amino acids (BCAA) were not cushioned either surpluses of isoleucine (Ile, expt 1) or valine (Val; expt 2) were avoided. In the fifth treatment, the effects of a simultaneous excess of Leu and Val (expt 1), or of Leu and Ile (expt 2) were investigated. The sixth treatment was a positive control. An increase in dietary Leu decreased growth performance, and increased plasma Leu and serum α-keto-isocaproate levels in a linear, dose-dependent manner. Levels of plasma Ile and Val, and of serum α-keto-β-methylvalerate and α-keto-isovalerate, indicated increased catabolism. Linear increases in the activity of basal branched-chain α-keto acid dehydrogenase in the liver confirmed these findings. No major alterations occurred in the mRNA of branched-chain amino acid catabolism genes. In liver tissue from expt 2, however, the mRNA levels of growth hormone receptor, insulin-like growth factor acid labile subunit and insulin-like growth factor 1 decreased significantly with increasing dietary Leu. In conclusion, excess dietary Leu increased the catabolism of BCAA mainly through posttranscriptional mechanisms. The impact of excess Leu on the growth hormone–insulin-like growth factor-1 axis requires further investigation.

High dietary intake of fats has been thought to be one of the major risk factors for the development of CVD. Less is known about the possible influence of fats from various sources on haemorheological abnormalities, which are considered an important factor in the pathogenesis of these diseases. The goal of the present study was to investigate effects of high-fat diets enriched in unsaturated fatty acids (USFA), SFA or trans-fatty acids (TFA), respectively, on haemorheological parameters in rats. Wistar female rats were divided into four groups and fed diets based on the AIN-93M formulation containing approximately 10 % energy from soyabean oil (control group) or 40 % energy from soyabean oil (USFA), palm oil (SFA) and vegetable shortening (TFA) for 8 weeks. The results showed that rats fed high-fat diets exhibited significant increases in serum TAG levels (P < 0·01), plasma viscosity (P < 0·01), whole blood viscosity (P < 0·01) and internal viscosity (P < 0·01) compared to the controls. The TFA group showed a significant decrease in erythrocyte deformability (P < 0·01) and increase in internal viscosity (P < 0·01) compared with the other groups. In addition, a significant increase in blood levels of free radicals (P < 0·01) was found in the TFA group, suggesting that the attack of oxygen-free radicals could be responsible for the impaired erythrocyte deformability. These impairments could be partly responsible for the development of various circulatory disorders. The present haemorheological study provides additional insights into the potential adverse effects of trans-fat and high-fat diets on haemorheological parameters.

We used a factorial approach to distinguish maintenance from growth requirements for protein, lysine and methionine in the black tiger shrimp, Penaeus monodon. Juvenile P. monodon (initial weight 2·4 g) were fed during 6 weeks one of ten semi-purified diets based on casein and purified amino acids (AA) as N source. The diets contained four levels of crude protein (CP, from 5 to 54 % DM diet) with two levels (% CP) of lysine or methionine (normal or 30 % deficient). Requirements were determined using linear and non-linear regression models. We could thus obtain the first ever data on maintenance (N equilibrium) requirements for CP and AA in P. monodon. CP requirements for maintenance (4·5 g/kg body weight (BW) per d) represented approximately 19 % of the CP requirement for maximal N gain (23·9 g/kg BW per d). The marginal efficiency of utilisation reached a maximum of 38 % for N, 0·77 for lysine and 1·62 for methionine using N gain as response. Lysine requirements were 0·20 g/kg BW per d for N maintenance and 1·40 g/kg BW per d for maximal N gain. Methionine requirements were 0·11 g/kg BW per d for N maintenance and 0·70 g/kg BW per d for maximal N gain. The lysine (5·8 %) and methionine (2·9 %) requirements for maximal N gain, expressed as percentage of protein requirement, agree with literature data using a dose–response technique with smaller P. monodon. The observed interaction between dietary CP and methionine for N gain demonstrates that requirements for indispensable AA (expressed as % CP) cannot be evaluated separately from CP requirements.

Maternal protein restriction in rat pregnancy is associated with altered feeding behaviour in later life. When allowed to self-select their diet, rats subject to prenatal undernutrition show an increased preference for fatty foods. The main aim of the present study was to evaluate the contribution of folic acid in the maternal diet to programming of appetite, since disturbances of the folate and methionine–homocysteine cycles have been suggested to impact upon epigenetic regulation of gene expression and hence programme long-term physiology and metabolism. Pregnant rats were fed diets containing either 9 or 18 % casein by weight, with folate provided at either 1 or 5 mg/kg diet. Adult male animals exposed to low protein (LP) in fetal life exhibited increased preference for high-fat food. Providing the higher level of folate in the maternal diet prevented this effect of LP, but offspring of rats fed 18 % casein diet with additional folate behaved in a similar manner to LP-exposed animals. Among day 20 gestation fetuses, it was apparent that both protein restriction and maternal folate supplementation could have adverse effects upon placental growth. Examination of methionine–homocysteine and folate cycle intermediates, tissue glutathione concentrations and expression of mRNA for methionine synthase, DNA methyltransferase 1 and methyltetrahydrofolate reductase revealed no gross disturbances of folate and one-carbon metabolism in either maternal or fetal tissue. The present findings indicated that any role for DNA methylation in programming of physiology is not related to major perturbations of folate metabolism, and is likely to be gene-specific rather than genome-wide.

Dark chocolate (DC) may be cardioprotective by antioxidant properties of flavonoids. We investigated the effect of DC (860 mg polyphenols, of which 58 mg epicatechin) compared with white chocolate (WC; 5 mg polyphenols, undetectable epicatechin) on plasma epicatechin levels, mononuclear blood cells (MNBC) DNA damage and plasma total antioxidant activity (TAA). Twenty healthy subjects followed a balanced diet (55 % of energy from carbohydrates, 30 % from fat and 1 g protein/kg body weight) for 4 weeks. Since the 14th day until the 27th day, they introduced daily 45 g of either WC (n 10) or DC (n 10). Whole experimental period was standardised in antioxidant intake. Blood samples were collected at T0, after 2 weeks (T14), 2 h and 22 h after the first chocolate intake (T14+2 h and T14+22 h), and at 27th day, before chocolate intake (T27), 2 h and 22 h after (T27+2 h and T27+22 h). Samples, except for T14+2 h and T27+2 h, were fasting collected. Detectable epicatechin levels were observed exclusively 2 h after DC intake (T14+2 h = 0·362 (se 0·052) μmol/l and T27+2 h = 0·369 (se 0·041) μmol/l); at the same times corresponded lower MNBC DNA damages (T14+2 h = − 19·4 (se 3·4) % v. T14, P < 0·05; T27+2 h = − 24 (se 7·4) % v. T27, P < 0·05; T14+2 hv. T27+2 h, P = 0·7). Both effects were no longer evident after 22 h. No effect was observed on TAA. WC did not affect any variable. DC may transiently improve DNA resistance to oxidative stress, probably for flavonoid kinetics.

The Thriposha programme is a community-level nutrition intervention in Sri Lanka that provides a combination of energy, protein and micronutrients as a ‘ready-to-eat’ cereal-based food. We measured the bioavailability of Fe and Zn from Thriposha formula at two different molar ratios of Zn:Fe in order to determine the effect on Fe and Zn absorption. Children 4–7 years (n 53) were given a meal prepared with 50 g Thriposha containing 1·5 mg Zn as zinc sulphate and either 9 mg (high Fe concentration (HiFe)) or 4·5 mg (low Fe concentration (LoFe)) Fe as ferrous fumarate. Zn and Fe percent absorption were measured using stable isotopes by tracer:tracee ratio and by incorporation of erythrocytes, respectively. Percent Fe absorption from the two meals was similar (6·6 % (4·8) v. 4·8 % (2·6); P = 0·15), but total Fe absorption was significantly higher from the HiFe meal (0·59 (0·43) mg) than the LoFe meal (0·20 (0·12) mg; P = 0·01). There was no significant difference between the two groups in Zn absorption (10·7 % (0·9) v. 8·8 % (1·4), P = 0·13, respectively). Decreasing the amount of Fe in Thriposha did not cause a significant change in the percent absorption of Fe and Zn, but significantly lowered the total amount of absorbed Fe. These results demonstrate the utility of maintaining a higher Fe content in this supplement. Further studies to increase Zn content are warranted while maintaining a HiFe.

Honey is an established traditional medicine with a variety of putative nutritional and health effects, including antibacterial, antioxidant, anti-inflammatory and prebiotic. The aim of the present study was to investigate the safety of consuming manuka honey, UMF® 20+, on healthy individuals by establishing whether UMF® 20+caused an allergic response (as measured by IgE levels), changed major commensal and beneficial microbial groups in the gut and/or affected levels of one of the most common advanced glycation endpoints, Nɛ-(carboxymethyl)-lysine (CML). The study had a randomised, double-blind cross-over design. A total of twenty healthy individuals aged 42–64 years were recruited. We tested two different honeys– a multiflora honey and UMF® 20+, both produced by Comvita New Zealand Ltd (Te Puke, New Zealand). Multiflora honey or UMF® 20+(20 g) was consumed daily for 4 weeks, with a 2-week ‘washout’ period in between. Blood samples were collected every week for each intervention period and used to measure total IgE levels in serum and advanced glycation endproducts – a consequence of methyglyoxal accumulation. Faecal samples were collected at the beginning and end of each 4-week period. DNA was extracted from faecal samples and the levels of a number of microbial groups in the gut, both beneficial and commensal, were analysed. Neither product changed the levels of IgE or CML or altered gut microbial profiles during the trial, confirming that UMF® 20+is safe for healthy individuals to consume. Despite anecdotal evidence suggesting that manuka honey is good for digestive health, we observed no beneficial effects on lower gut bacterial levels with either honey in this healthy population.

Consumption of resistant starch (RS)-enriched foods is associated with decrease in the postprandial glycaemic and insulinaemic responses, accompanied by the production of fermentation-related gases in the large bowel. The present study aimed to determine the postprandial glycaemic and insulinaemic responses to the GM RS-enriched rice and the fermentation-related production of H2 in young and healthy Chinese adults. A total of sixteen young adults (nine men and seven women) were recruited and divided into three groups. Their postprandial glycaemic and insulinaemic responses to 40 g glucose, carbohydrates of RS or wild-type (WT) rice were tested by a crossover model with a washout period of 7 d. The concentrations of blood glucose and insulin as well as breath H2 were measured before and after food intake. Although the mean concentrations of fasting blood glucose, insulin and breath H2 were similar, consumption of the RS rice significantly decreased the values of glycaemic index (GI) and insulin index (II), as compared with the intake of WT rice (48·4 (sem 21·8) v. 77·4 (sem 34·9) for GI, 34·2 (sem 18·9) v. 54·4 (sem 22·4) for II, P < 0·05), respectively. Conversely, intake of the RS rice meal significantly elevated the concentrations of breath H2, as compared with WT rice (38·9 (sem 17·6) v. 10·5 (sem 3·7) parts per million for peak levels of breath H2, P < 0·05) through a period of 16-h tests. Consumption of the GM RS-enriched rice meal decreased the postprandial glycaemic and insulinaemic responses and promoted RS fermentation-related production of H2 in the large bowel of young and healthy Chinese adults.

Two independent cross-sectional dietary surveys (the Individual and National Food Consumption Surveys, INCA), performed in 1998–99 (INCA1) and in 2006–07 (INCA2) on nationally representative samples of French people, were used to analyse trends in the dietary habits and nutritional intake of French adults. Food consumption was recorded through 7-d dietary records, and nutritional intakes were assessed using the French food composition database. After exclusion of under-reporters, analyses were performed on 3267 adults, aged 18–79 years: 1345 from INCA1 and 1922 from INCA2. The trends highlighted over the 8-year period showed a decrease in consumption of dairy products, meat, bread, potatoes, pastries/croissant-like pastries/cakes/biscuits and sugar/confectionery. In contrast, the consumption of fruits and vegetables, rice, ice cream and chocolate increased. Other food groups, like fish and snacking foods, remained stable. Food choices were mostly age specific. These age differences remained consistent over the years and underlined two opposite dietary trends: a ‘traditional’ one mainly followed by the elderly, and a ‘snacking and convenience’ one mainly adopted by young adults. The overall trends in food consumption did not influence the mean energy intake, but did slightly modify the contribution of each macronutrient to energy intake. These repeated surveys highlighted the fact that trends in French food habits have moved towards an average European diet at the crossroads between Mediterranean and Northern diets, and that food consumption changes impacted, to a lesser extent, nutritional intake.

The association of dietary glycaemic index (GI) and glycaemic load (GL) with CVD has been examined in several populations with varying results. We tested the hypothesis that women with diets high in GI or GL would have higher rates of myocardial infarction (MI), and the associations would be stronger in overweight women. We measured dietary GI and GL in 36 234 Swedish Mammography Cohort participants aged 48–83 years using FFQ. Cox models were used to calculate incidence rate ratios (RR) and 95 % CI for hospitalisation or death due to MI assessed using the Swedish inpatient and cause-of-death registers from 1 January 1998 until 31 December 2006. Over 9 years of follow-up, 1138 women were hospitalised or died due to a first MI. In multivariable-adjusted models, the RR comparing top to bottom quartile of dietary GI were 1·12 (95 % CI 0·92, 1·35, P-trend = 0·24), and the RR comparing top to bottom quartile of dietary GL were 1·22 (95 % CI 0·90, 1·65, P-trend = 0·23). Among overweight women, the RR comparing top to bottom quartile of dietary GI were 1·20 (95 % CI 0·91, 1·58, P-trend = 0·22), and the RR comparing top to bottom quartile of dietary GL were 1·45 (95 % CI 0·93, 2·25, P-trend = 0·16). There were no statistically significant associations of dietary GI or GL with MI in this population.

While undernutrition and anaemia have previously been linked to poor development of children, relatively little is known about the role of B-vitamins and fatty acids on cognition. The present study aims to explore the associations between indicators of body size, fatty acid and micronutrient status on cognitive performance in 598 Indian school children aged 6–10 years. Baseline data of a clinical study were used to assess these associations by analyses of variance adjusting for age, sex, school, maternal education and cognitive tester. The Kaufman Assessment Battery for Children II was used to measure four cognitive domains, including fluid reasoning, short-term memory, retrieval ability and cognitive speediness. Scores were combined into an overall measure, named mental processing index (MPI). Body size indicators and Hb concentrations were significantly positively related to cognitive domains and MPI, such that increases of 1 sd in height-for-age and weight-for-age z-scores would each translate into a 0·09 sd increase in MPI, P = 0·0006 and 0·002, respectively. A 10 g/l increase in Hb concentrations would translate into a 0·08 sd increase in MPI, P = 0·0008. Log-transformed vitamin B12 concentrations were significantly inversely associated with short-term memory, retrieval ability and MPI (β (95 % CI) = − 0·124 ( − 0·224, − 0·023), P = 0·02). Other indicators of Fe, iodine, folate and fatty acid status were not significantly related to cognition. Our findings for body size, fatty acids and micronutrients were in agreement with previous observational studies. The inverse association of vitamin B12 with mental development was unexpected and needed further study.

The aim of the present study was to compare body fat percent (BF %) using single-site near-IR reactance (NIR) and dual-energy X-ray absorptiometry (DXA) in a cohort of normal-weight (BMI < 25 kg/m2) black (n 102) and white (n 71); and obese (BMI ≥ 30 kg/m2) black (n 117) and white (n 41) South African women (18–45 years). NIR-derived BF % was significantly correlated with DXA-derived BF % in all groups: normal-weight black (r 0·55, 95 % CI: 0·40, 0·67, P < 0·001) and white (r 0·69, 95 % CI: 0·53, 0·79, P < 0·001) women; obese black (r 0·59, 95 % CI: 0·46, 0·70, P < 0·001) and white (r 0·56, 95 % CI: 0·30, 0·74, P < 0·001) women. NIR under-predicted BF% compared to DXA in black women (normal-weight, − 4·36 (sd 4·13) % and obese, − 3·41 (sd 3·72) %), while smaller mean differences were observed in white women (normal-weight, − 0·29 (sd 4·19) % and obese, − 0·81 (sd 3·09) %), irrespective of normal-weight or obese status (P < 0·001). In obese subjects, NIR-derived BF % did not measure values greater than approximately 45 %, while the maximum DXA-derived measure was 58 %. In conclusion, although there was a significant relationship between NIR- and DXA-derived BF %, NIR under-predicted BF % in normal-weight and obese black South African women compared to DXA, but to a greater extent in subjects with very high levels of adiposity (>45 %). The results of single-site NIR as a measure of BF % should therefore be interpreted with caution, particularly in women of African descent and in those with very high levels of adiposity.

A cross-sectional study was carried out in order to compare intestinal microbiological and immunological biomarkers with blood glucose and lipids, satiety-related hormones and inflammatory biomarkers characterising differences between obese and normal weight subjects. Faecal and blood samples were obtained from twenty obese subjects with an average BMI of 32·9 kg/m2 and twenty normal weight subjects with an average BMI of 23·3 kg/m2. Blood insulin, TAG and leptin were significantly elevated, whereas concentrations of HDL and ghrelin were significantly decreased in the obese subjects. Inflammatory status in the obese subjects was characterised by a trend for elevated blood C-reactive protein (CRP; P = 0·06) and IL-6 (P = 0·02). The faecal microbial composition differed between the groups; less sulphate-reducing bacteria (P = 0·05) and a trend for less Bacteroides (P = 0·07) were measured for overweight subjects. Furthermore, an inverse correlation was demonstrated between faecal Bacteroides levels and waist circumference (P = 0·05). The faecal microbial metabolites differed between the groups; increased concentrations of branched-chain fatty acids, phenolics, valeric acid, di- and hydroxy acids were described in the obese subjects. No differences between the measured intestinal inflammatory biomarkers were detected. However, systemic inflammation (CRP and IL-6) was correlated with the faecal concentrations of phenolics and lactic acid (P < 0·05 and 0·05, and P < 0·01 and 0·05, respectively). In summary, weight-related differences were observed both in the intestinal microbial composition and its activity. The role of intestinal signals, such as phenolics and lactic acid in the development of weight-related problems, needs to be studied further.