Legislation is described that impacts on the use of low-digestible carbohydrates in foods. This includes controls on the use of these carbohydrates, mandatory labelling concerned with gastrointestinal effects, nutrition labelling, and nutrition and other claims. Regional differences in approach to legislation have led to inconsistencies in the information that must be provided to consumers, even for the same food products. Also, within regions, different regulations apply to food carbohydrates that may be classified similarly from the physiological perspective. Consistency of food labelling globally and in application to similar carbohydrates would benefit from greater attention to the underpinning science.

The present study investigated the relative importance of glutamine as a transamination source in the ovine liver by examination of the labelling of amino acids (AA) in the hepatic free pool, mixed liver and plasma proteins of fed and fasted sheep, following infusion of isotopically-labelled glutamine. In a cross-over design four sheep were either fasted for 3 d or fed to 1·2×energy maintenance and finally euthanased. At each intake, the sheep were infused for 6 h with [2-15N]glutamine (150 μmol/h) and samples of total plasma protein isolated. Following the terminal infusion, liver tissue total proteins were prepared and hydrolysed and 15N-enrichments in seventeen AA were determined by GC–combustion–isotope-ratio mass spectrometry. All AA were enriched (relative to natural abundance) except lysine and threonine, with the lowest enrichments in phenylalanine and histidine. There was no effect of the fed v. fasted state, except for leucine and isoleucine in liver protein (P<0·05). Enrichments in liver protein were greater than in plasma protein (P<0·01, except proline) and probably reflect the faster turnover rate of hepatic constitutive proteins compared with export proteins. Amination to methionine was greater than that to phenylalanine (P<0·01), suggesting a mechanism for preferentially protecting the former. This factor could be important for ruminant production, as methionine is often considered to be the first limiting AA for animals offered certain silages and conserved forages. Enrichments in all AA (except for glutamine, alanine and aspartate) were less than that for glutamate (P<0·01), and thus transaminations may have occurred with glutamine directly or via glutamate, following the action of hepatic glutaminase.

Increased folate intake reduces the risk of neural tube defects, other malformations and also possibly, pregnancy complications. Increasing evidence suggests that the beneficial effect of folate may be related to improved function of methionine synthase, a vitamin B12-dependent enzyme that converts homocysteine to methionine. In India, the majority of the population adheres to a vegetarian diet known to be deficient in vitamin B12. In such a population, increased folate intake may offer minimal protection against birth defects, whereas vitamin B12 administration should be considered. In this review, is described the metabolism of and interrelations between folate, vitamin B12 and homocysteine. This is followed by a brief discussion of some of the proposed mechanisms for their biological effects in relation to birth defects and pregnancy outcome.

The effects of an exogenous enzyme preparation, the application method and feed type on ruminal fermentation and microbial protein synthesis were investigated using the rumen simulation technique (Rusitec). Steam-rolled barley grain and chopped alfalfa hay were sprayed with water (control, C), an enzyme preparation with a predominant xylanase activity (EF), or autoclaved enzyme (AEF) 24 h prior to feeding, or the enzyme was supplied in the buffer infused into the Rusitec (EI). Microbial N incorporation was measured using (15NH4)2SO4 in the buffer. Spent feed bags were pummelled mechanically in buffer to segregate the feed particle-associated (FPA) and feed particle-bound (FPB) bacterial fractions. Enzymes applied to feed reduced neutral-detergent fibre content, and increased the concentration of reducing sugars in barley grain, but not alfalfa hay. Ruminal cellulolytic bacteria were more numerous with EF than with C. Disappearance of DM from barley grain was higher with EF than with C, but alfalfa was unaffected by EF. Treatment EF increased incorporation of 15N into FPA and FPB fractions at 24 and 48 h. In contrast, AEF reduced the 24 h values, relative to C; AEF and C were similar at 48 h. Infused enzyme (EI) did not affect 15N incorporation. Xylanase activity in effluent was increased by EF and EI, compared to C, but not by AEF. Xylanase activity in FPA was higher at 48 h than at 24 h with all treatments; it was higher with EF than C at 24 and 48 h, but was not altered by AEF or EI. Applying enzymes onto feeds before feeding was more effective than dosing directly into the artificial rumen for increasing ruminal fibrolytic activity.

To clarify the bioavailability of vitamin B12 in lyophylized purple laver (nori; Porphyra yezoensis), total vitamin B12 and vitamin B12 analogue contents in the laver were determined, and the effects of feeding the laver to vitamin B12-deficient rats were investigated. The amount of total vitamin B12 in the dried purple laver was estimated to be 54.5 and 58.6 (SE 5.3 and 7.5 respectively) ΜG/100 g dry weight by lactobacillus bioassay and chemiluminescent assay with hog intrinsic factor respectively. the purple laver contained five types of biologically active vitamin b12 compounds (cyano-, hydroxo-, sulfito-, adenosyl- and methylcobalamin), in which the vitamin b12 coezymes (adenosyl- and methylcobalamin) comprised about 60 % of the total vitamin b12. when 9-week-old vitamin b12-deficient rats, which excreted substantial amounts of methylmalonic acid (71.7(se 20.2) μmol/d) in urine, were fed the diet supplemented with dried purple laver (10 μg/kg diet) for 20 d, urinary methylmalonic acid excretion (as an index of vitamin B12 deficiency) became undetectable and hepatic vitamin B12 (especially adenosylcobalamin) levels were significantly increased. These results indicate that vitamin B12 in dried purple laver is bioavailable to rats.

From a public health perspective, some of the new insights into folic acid nutrition are of significance. Folate intake recommendations vary under different conditions. Intake of 350 μg is required to maintain plasma homocysteine levels, 650 μg for those with elevated plasma homocysteine, about 400 μg for women planning to become pregnant and 4000 μg for those with history of neural tube defect affected pregnancy. This raises the question whether the folate intake is adequate for the general population, particularly in the vulnerable groups or whether there is a need for scientists to take a fresh view of the requirements, recommended dietary intakes, and consider intervention measures which will have impact on the folate nutritional status. The recommendations should provide a margin of safety to allow for decreased intake, increased requirements, individual variability and bioavailability of natural food folates. The folate intake and nutriture in relation to India and other developing countries needs careful consideration to reduce anemia, neural tube defects and possibly impact on the high incidence of cardiovascular diseases.

Infant formula based on pea (Pisum sativum)-protein isolate has been suggested as an alternative to soyabean formula in countries where soyabean is not a native crop, or when soyabean protein cannot be used due to allergic reactions or intolerances. In the present study, Fe absorption from experimental infant formulas based on pea-protein isolate was measured in healthy non-anaemic young women. The influence of phytic acid and ascorbic acid on Fe absorption was evaluated, using a stable-isotope technique based on incorporation of Fe stable-isotope labels into erythrocytes 14 d after administration. Geometric mean Fe absorption increased from 20·7 (+1SD 41·6, -1sd 10·3) % to 33·1 (+1sd 58·6, -1sd 18·7) %; (P<0·0001; n 10) after enzymic degradation of virtually all phytic acid. Doubling the molar ratio Fe : ascorbic acid from 1 : 2·1 to 1 : 4·2 in the infant formula with native phytic acid content also increased Fe absorption significantly (P<0·0001; n 10); geometric mean Fe absorption increased from 14·8 (+1sd 32·1, -1sd 6·8) % to 22·1 (+1sd 47·2, -1sd 10·4) %. These results confirm the inhibitory and enhancing effects of phytic acid and ascorbic acid respectively on Fe absorption, but also indicate relatively high fractional Fe absorption from the pea-protein-based formulas. After adjusting for differences in Fe status, our data indicate that Fe absorption from dephytinised pea protein might be less inhibitory than dephytinised soyabean protein as measured in a previous study ().

The objective of the present study was to describe the intake of dietary fatty acids among healthy 15-year-old boys and girls and to relate the intake of specific fatty acids and the fatty acid composition of the serum cholesterol esters to serum lipid, apolipoprotein (Apo) and insulin concentrations respectively. Fifty-two girls and forty-two boys were randomly selected from the official population register. Unexpectedly, significant inverse associations were found between the dietary content of saturated fatty acids with a chain length of four to fifteen C atoms, mainly derived from milk fat, as well as the corresponding fatty acids in the serum cholesterol esters, on the one hand and the serum concentrations of cholesterol and ApoB on the other. The estimated dietary intake of 4:0–10:0, 12:0 and 14:0 respectively, were all significantly inversely related to the serum cholesterol (r -0.32, r -0.31, r -0.30, all P<0.05) and ApoB (r -0.42, r -0.42, and r -0.40, all P<0.05) concentrations in girls and 12:0 to the ApoB concentration (r -0.55, P<0.01) in boys. The proportions of 12:0 and 15:0 in the serum cholesterol esters were negatively correlated with the serum cholesterol concentrations in both girls (r -0.34, r -0.32, P<0.05) and boys (r -0.53, P<0.01; r -0.32, P<0.05) and with the ApoB concentrations among boys (r -0.61, P<0.01; r -0.43, P<0.05). It is conceivable that milk fat contains or is associated with some component in the diet, or some other characteristics of the food intake, which counterbalances the expected positive relationships between saturated fat intake and lipid levels.

This experiment aimed to investigate the influence of folic acid supplements on the carry-over of folates from the sow to the fetus during late gestation and to the suckling piglet. Two groups of sixteen German Landrace sows received, during gestation and lactation, a diet supplemented with either 0 or 10 mg folic acid/kg. Increased folic acid concentrations in the serum of sows were detected only at the end of gestation (day 100) and at the end of lactation (day 28). The supplementation with folic acid to the sows' diet improved the folic acid supply of the fetus compared with unsupplemented controls; values were respectively 92.6 v. 56.2 nmol folates/l serum in newborn piglets and 171.9 v. 76.3 μmol folates/g fresh liver in stillborn piglets (P < 0.05). Folate concentrations in colostrum and milk (day 28) were 3.6- and 5.0-times higher in supplemented than unsupplemented sows. This treatment effect was also reflected in the serum of piglets until weaning. Therefore, the folic acid supply for the suckling piglet is dependent mainly upon the carry-over of maternal folates via colostrum and milk.

The trend towards an increased consumption of minimally processed plant food results in a higher intake of non-nutritive compounds such as lectins. Lectins are typically globular proteins that are resistant to digestion in the gastrointestinal tract. They affect the integrity of the intestinal epithelium and the absorption of dietary antigens, and induce the release of allergic mediators from mast cells in vitro. Based on this information we have studied whether dietary wheat germ agglutinin (WGA) could be involved in triggering food allergies. Brown Norway rats were immunized intraperitoneally using ovalbumin (OVA; 10 μg/rat) and 10 d later treated for five consecutive days with WGA (10 mg/rat per d) administered intragastrically. Rats were then orally challenged with OVA (100 μg/rat) 1 h after the last WGA application, and blood was collected 4 h later. Immunological responses (anti-OVA immunoglobulins E and G, rat mast cell protease II, interferon-γ and lymphocyte proliferation) were measured and lymphocyte subpopulations were determined. In immunized rats WGA treatment resulted in increased serum rat mast cell protease II concentrations (pre-challenge 0.26 (SE 0.08) ΜG/ML, POST-CHALLENGE 0.49 (se 0.09) μg/ml; P<0.01) 4 h after the OVA challenge. After 5 d serum concentrations of anti-OVA immunoglobulin E were significantly increased only in the immunized controls (absorbance at 405 nm on days 14 and 19 was 0.09 (se 0.008) and 0.24 (se 0.046) respectively; P=0.02), while in WGA-treated rats no significant increase was seen (0.08 (se 0.004) and 0.15 (se 0.037 respectively; P=0.14). CD4+ : CD8+ T lymphocytes in the spleen was significantly increased at this time (OVA 1.1 (sd 0.2), OVA+WGA 1.4 (sd 0.1), P<0.05). The treatment did not impair the proliferation and interferon-γ production of mesenteric lymphocytes. In conclusion, these data suggest that high dietary intake of lectins such as WGA may affect the allergic response towards oral antigens in the gut-associated lymphoid tissue.

Four donkeys and four ponies were fed molassed dehydrated alfalfa or oat straw, either ad libitum or restricted to about 70 % ad libitum intake in a Latin-square design for four periods of 21 d. Measurements of apparent digestibility and gastrointestinal transit time were made on the last 7 d of each period. When the forages were provided ad libitum, all animals ate significantly (P<0.01) more of the alfalfa than of the oat straw. Ponies consumed significantly (P = 0.007) more of both diets per unit live weight than donkeys. Higher apparent digestibilities of dietary DM, energy and fibre fractions were seen in donkeys, at both levels of feeding, compared with the ponies. This partly compensated for the lower intakes by the donkeys when fed ad libitum. When intake of alfalfa was restricted, the apparent digestibility of DM was higher compared with the corresponding values when fed ad libitum, but the reverse was true for straw. This may be because restriction of a low-quality diet reduced selection of the more digestible parts of the forage. Donkeys and ponies consumed more energy and protein than required when fed alfalfa ad libitum. Both oat straw treatments provided insufficient protein to meet the predicted requirements of ponies and donkeys. Straw intakes ad libitum exceeded the estimated energy requirement for ponies by 34–51 %, but donkey energy requirements were only just met. When the amount of straw offered was restricted, 78–90 % of the estimated energy requirement for donkeys was met compared with 90–105 % for the ponies.

The aim of the present work was to analyse the hypocholesterolaemic efficiency of a Vicia faba-protein isolate in relation to the intact legume. In addition, the mechanisms underlying the effects of this isolate were investigated. Hypercholesterolaemic rats were divided into three groups (n 10×3) and fed high-fat diets rich in cholesterol-containing casein, whole seeds of Vicia faba or the protein isolate of faba beans as protein source, for 2 weeks ad libitum. The protein isolate was prepared by isoelectric precipitation and spray dried. Analyses of serum, liver and faeces, as well as of the activity of hepatic 3-hydroxy-3-methylglutaryl (HMG)-CoA reductase, were assessed by enzymatic methods. The rats fed on Vicia faba diets showed significantly lower body weights and energy intakes than rats fed on casein diets. The whole-seed diet induced a significant reduction in plasma triacylglycerol. Feeding rats on diets containing faba bean seeds, or the protein isolate, induced a significant decrease in plasma (LDL+VLDL)-cholesterol but not in HDL-cholesterol. Hepatic cholesterol and triacylglycerol were also reduced. The hypocholesterolaemic effects of Vicia faba were not the result of a reduction in cholesterol synthesis as assessed from HMG-CoA reductase activity, but the result of an increase in steroid faecal excretion. The faba bean-protein isolate obtained under our experimental conditions was useful in improving the metabolic alterations induced by feeding with a hypercholesterolaemic diet compared with casein. The effectiveness of the whole seeds was higher than that of the protein isolate.

During atherogenesis, a pathological accumulation of lipids occurs within aortic intimal macrophages through uptake of oxidised LDL via scavenger receptors. Here we investigated whether some of the anti-atherosclerotic effects ascribed to an olive oil rich-diet are mediated through effects on macrophage scavenger receptors (MSR). Male C57 Bl6 mice aged 6 weeks were fed for 12 weeks on a low-fat diet (containing 25 g corn oil/kg) or on high-fat diets containing 200 g coconut oil, olive oil or safflower oil/kg. Thioglycollate-elicited peritoneal macrophages were analysed for fatty acid composition by GC and the levels of mRNA coding for three MSR (MSRA type I, MSRA type II and CD36) were measured by reverse-transcription polymerase chain reaction. Feeding mice diets enriched with different fats resulted in significant differences in the fatty acid profile of macrophages, which reflected the fatty acid compositions of the diets. These differences were accompanied by a lower level of mRNA for MSRA type I, MSRA type II and CD36 in macrophages from mice fed an olive-oil-enriched diet compared with the mice fed on the low-fat diet. These data suggest that part of the protective effect of olive oil against atherosclerosis might be via reducing macrophage uptake of oxidised LDL. Whether this effect is due to the downregulation of gene transcription directly by unsaturated fatty acids or is the result of the effect of monounsaturated fatty acids or other components of olive oil on LDL composition and oxidation remains to be ascertained.

Zinc is an essential mineral and deficiency results in abnormal immune function and higher rates of infectious diseases. Randomized controlled trials of zinc supplementation have been conducted in children in developing countries to determine effects on infectious disease morbidity and mortality. Zinc-supplemented children have been found to have lower rates of diarrhea, pneumonia and malaria in comparison with children not given zinc. Zinc used as an adjunct to fluid and dietary management of acute and persistent diarrhea has been found to reduce diarrheal duration and severity. Preliminary evidence suggests that zinc supplementation in children in poor developing country settings may also reduce infant mortality, but larger trials are needed to address this important issue. Preventive and therapeutic interventions should be implemented in developing countries where zinc deficiency is likely to be prevalent.

We investigated the gastrointestinal handling and post-absorptive metabolic handling of [1,1,1-13C]tripalmitin and [1-13C]glycocholate during recovery from severe childhood malnutrition. Eight children were studied on three occasions: at admission (phase 1), during rapid catch-up growth (phase 2) and when weight-for-height had reached 90 % of the reference (phase 3). Breath samples were obtained over a 24 h period and stools were collected over 3 d following the administration of each tracer. At admission, the lipid content of stool expressed as a percentage of ingested lipid was 6 (range 0.7–28.9) but less variation was shown between children at phase 2 (3.3 (range 0.9–4.1)) and phase 3 (1.4 (range 0.4–2.5)). The excretion of 13C in stool varied markedly between children at admission (11.1 (SD 5.4) % administered dose) and during rehabilitation (phase 2, 15.4 (sd 16.5) % administered dose; phase 3, 6.2 (sd 10.2) % administered dose). About 5 % of the absorbed label was recovered on breath at each stage (% absorbed dose; phase 1, 5.1 (sd 6.0); phase 2, 5.2 (sd 3.1); phase 3, 6.4 (sd 6.6)). None of the children exhibited significant bile salt malabsorption as a consequence of small intestinal overgrowth. Of the 13C measured in stool, more label was recovered in fatty acids than triacylglycerols during each of the three phases and this was interpreted to reflect a failure to absorb the products of digestion. The results show that not all the children had problems associated with the digestion and absorption of 13C-labelled tripalmitin in severe malnutrition and during recovery, which was not reflected in gross lipid balance across the gastrointestinal tract. Absorbed lipid was more likely to be deposited as adipose tissue than to satisfy the immediate needs for energy.

The effect of dietary fibre on the gastric emptying rate of solids is controversial. Similarly, the mechanisms by which it modulates food intake are partially unknown. Gastric emptying and proximal v. distal stomach filling were evaluated in triplicate on four conscious pigs using scintigraphic imaging. Each animal received in an isoenergetic manner a concentrate low-fibre diet enriched in starch (S) and two high-fibre diets based on sugar beet pulp (BP) or wheat bran (WB). All meals had the same viscosity before ingestion (100.0–100.5 Pa.s). Viscosity of the gastric contents was measured in four additional animals fitted with a gastric cannula. The gastric emptying rate of BP diet was significantly slower than S and WB diets (t1/2 78.4 (SEM 5.68), 62.8 (sem 10.01) and 111.6 (sem 10.82) min for S, WB and BP diets respectively, P<0.05). For BP diet only, rate of distal stomach filling was steady during the first 120 min after the meal whereas that of S and WB diets decreased in an exponential manner. Numerous backflow episodes from the distal into the proximal stomach were observed for BP diet that generated the larger intragastric viscosity (0.26 (sem 0.03), 0.3 (sem 0.02) and 0.52 (sem 0.002) Pa.s for S, WB and BP respectively). In conclusion, viscosity of the meal or the percentage total fibre, unlike viscosity of the gastric contents, are poor predictors for emptying. The reduced emptying rate observed with BP is associated with major changes in intragastric distribution of the meal absent with WB and S diets.

This cross-sectional study compared body fat percentage (BF%) obtained from a four-compartment (4C) model with BF% from hydrometry (using 2H2O), dual-energy X-ray absorptiometry (DXA) and densitometry among the three main ethnic groups (Chinese, Malays and Indians) in Singapore, and determined the suitability of two-compartment (2C) models as surrogate methods for assessing BF% among different ethnic groups. A total of 291 subjects (108 Chinese, seventy-six Malays, 107 Indians) were selected to ensure an adequate representation of age range (18–75 years) and BMI range (16–40 kg/m2) of the general adult population, with almost equal numbers from each gender group. Body weight was measured, together with body height, total body water by 2H2O dilution, densitometry with Bodpod® and bone mineral content with Hologic® QDR-4500. BF% measurements with a 4C model for the subgroups were: Chinese females 33.5 (SD 7.5), CHINESE MALES 24.4 (sd 6.1), Malay females 37.8 (sd 6.3), Malay males 26.0 (sd 7.6), Indian females 38.2 (sd 7.0), Indian males 28.1 (sd 5.5). Differences between BF% measured by the 4C and 2C models (hydrometry, DXA and densitometry) were found, with underestimation of BF% in all the ethnic-gender groups by DXA of 2.1–4.2 BF% and by densitometry of 0.5–3.2 BF%). On a group level, the differences in BF% between the 4C model and 2H2O were the lowest (0.0–1.4 BF% in the different groups), while differences between the 4C model and DXA were the highest. Differences between the 4C model and 2H2O and between the 4C model and DXA were positively correlated with the 4C model, water fraction (fwater) of fat-free mass (FFM) and the mineral fraction (fmineral) of FFM, and negatively correlated with density of the FFM (DFFM), while the difference between 4C model and densitometry correlated with these variables negatively and positively respectively (i.e. the correlations were opposite). The largest contributors to the observed differences were fwater and DFFM. When validated against the reference 4C model, 2C models were found to be unsuitable for accurate measurements of BF% at the individual level, owing to the high errors and violation of assumptions of constant hydration of FFM and DFFM among the ethnic groups. On a group level, the best 2C model for measuring BF% among Singaporeans was found to be 2H2O.