The present study investigates the prevalence and type of anaemia in Chinese female cotton mill workers. The prevalence of anaemia is reported in 447 non-pregnant female workers aged between 19 and 45 years. The mean value for haemoglobin (Hb) was 123 (SD 15) g/l and 150 of the total 447 subjects had Hb values below 120 g/l; thus 34% of the population was anaemic according to World Health Organization (WHO, 1975) criteria. The mean value for free erythrocyte protoporphyrin (FEP) was 419 (SD 215) μg/l; 55% of the total population had FEP values higher than 350 μg/l and 72% among the anaemic subjects. Serum ferritin (SF) was tested in all the women with a Hb value less than 120 g/l and 71 % of them had SF values below 12·0 μg/ls. Eighty women diagnosed as either Fe deficient or with Fe-deficient anaemia were selected for a diagnostic supplementation trial. They were randomly assigned to FeSO4 (60 or 120 mg Fe/d) or placebo treatment for 12 weeks. Fe supplementation increased mean Hb values from 114 to 127 g/l (P < 0·001) and SF levels from 9·7 to 30·0 μg/l (P < 0·001), and decreased mean FEP values from 570 to 277 μg/l (P < 0·001). The response rate of Hb in the whole Fe-treated group or Fe-treated subjects with an Hb level less than 120 g/1 was 90 % or 92 % respectively. These findings indicate that the type of anaemia in this population was mainly Fe deficiency. It was also found that in this population the severity of anaemia, not the prevalence, was significantly related to the use of intra-uterine devices (IUD).

Adult male pigs were fed on a diet containing (% of energy) fat 25 starch 55 from white rice and providing 20 g fibre/pig per d (diet WR). In two other groups rice bran was added to the diet to provide 43 g fibre/d. One group received the diet unmodified (diet RB), but in another (diet RO) heat-stabilized unrefined rice oil replaced the palm oil. In a further group brown rice replaced white rice and provided 37 g fibre/pig per d (diet BR). Plasma cholesterol concentrations were similar with diets WR, RB and BR. With diet RO the concentration was significantly lower than with diets WR and BR but was not different from diet RB. Plasma high-density-lipoprotein-cholesterol and plasma triacylglycerols were unaffected by diet. In all groups, digesta mass rose from the caecum to the proximal colon but fell in the distal colon. Diet WR gave the lowest digesta mass while diet BR gave a significantly higher mass along the large bowel length. RB- and RO-fed pigs had equal masses of digesta which were intermediate between BR- and WR-fed pigs at all sampling sites. Pools of individual and total volatile fatty acids (VFA) in the proximal large bowel were unaffected by diet. Pools of total and individual VFA in the median and distal colon were lowest with diets WR and RB and significantly higher with diet BR. In these regions of the colon pools of acetate in RO-fed pigs did not differ from those in the BR-fed group but were higher than in other groups. However, pools of propionate and butyrate with the RO diet were significantly lower than with diet BR and the same as with diets WR and RB. Portal venous VFA concentrations were unaffected by diet. The higher large bowel digesta masses and VFA with diet BR may reflect the escape of starch from the smallintestine.

The aim of the present study was to measure the effect of graded inclusion of baked beans (Phaseolus vulgaris) on plasma and liver lipids in hypercholesterolaemic pigs fed on a Western-type diet. Twenty- four Large White × Landrace pigs of about 30 kg body weight were made hypercholesterolaemic by feeding a semi-purified diet, high in saturated fat and supplemented with 10 g cholesterol/kg, for 14 d. After that, six pigs were randomly assigned to one of the four experimental groups. They received their respective diets, containing 0, 100, 200 or 300 g baked beans/kg, on a dry-matter basis, for a further 28 d. Fasting blood samples were taken and analysed for total plasma cholesterol, lipoproteins and triacylglycerols. After the pigs were slaughtered at the end of the study, livers were analysed for their cholesterol content. Consumption of baked beans at 100, 200 and 300 g/kg reduced plasma total cholesterol by 5·3, 20·2 and 35·6 % respectively. However, only the diet with 300 g baked beans/kg showed a significant reduction (P < 0·05) compared with the control (without baked beans)- The level of low-density-Hpoprotein-cholesterol was also significantly (P < 0·05) reduced by 48% at 300 g baked beans/kg. Plasma very-low-density-lipoprotein-cholesterol, high-density-lipoprotein-cholesterol and triacylgiycerol contents were not affected by bean consumption. The supplements of 200 and 300 g baked beans/kg promoted a significant (P < 0·05) reduction of about 50% in cholesterol deposition in the liver, compared with the control.

The tripeptide glutathione is proposed to be protective against a number of chronic diseases including cardiovascular disease and cancer. However, there have been few studies of plasma glutathione levels in humans and in those studies the numbers of participants have been very small. In an exploratory analysis the determinants of plasma total glutathione (GSHt) were investigated in a group of 100 volunteers aged 18–61 years in Atlanta, Georgia, USA during June and July 1989. Data on demographic and health-related factors were collected by interview and plasma GSHt was measured using a recently modified laboratory method. The mean concentration of plasma GSHt for all 100 participants was 761 μg/l, with a standard deviation of 451 μg/l, a range of 86–2889 μg/1 and a median of 649 μg/l. Men had significantly higher levels of plasma GSHt than women (924 v. 692 μg/l; P = 0·006). Seventh-day Adventists participating in the present study had higher plasma GSHt levels than other subgroups defined by race and/or religion. Among Seventh-day Adventists consumption of a vegetarian diet was associated with increased plasma GSHt concentration (P = 0·002). Plasma GSHt levels also appeared to vary by race, but relationships with race could not be clearly disassociated from relationships with religion. Among white participants plasma GSHt concentration decreased with age in women but increased with age in men (P = 0·05). Few other factors were associated with plasma GSHt concentration, although use of oral contraceptives (P = 0·10) was somewhat associated with decreased plasma GSHt levels. These findings suggest that plasma GSHt levels may vary with several demographic and health-related attributes and support the need for further research on this potentially important disease-preventive compound.

The purpose of the study was to assess the prevalence of Fe deficiency and Fe-deficiency anaemia in a group of apparently healthy adolescents, and to assess the value of a food frequency and amount questionnaire as a screening tool to identify children at risk of Fe deficiency. White schoolchildren (399) aged 12–14 years living in a Southwest London suburb completed a food frequency and amount questionnaire to assess usual Fe and vitamin C intake, and provided a thumb-prick blood sample for analysis of haemoglobin (Hb), packed cell volume (PCV), and serum ferritin (SF). Children were classified as ‘anaemic’ if Hb was below the Dallman 3rd percentile (girls: < 120 g/l; boys: < 122, < 124 and < 126 g/l at ages 12, 13 and 14 years respectively); and ‘low’ or ‘borderline’ in Fe stores if SF was < 12 μg/l, or between 12 and 20 μg/l respectively. Of the boys and girls 3·5 and 10·5% respectively were anaemic; 1% of boys and 4% of girls had low ferritin values, and 14% of boys and 16% of girls were borderline. Fe intakes were significantly higher in boys than in girls (12·3 v. 9·6 mg/d, P < 0·001). Prevalence of anaemia was 14·5% in the group with both low Fe intakes (< lower reference nutrient intake) and low vitamin C intakes (< median), compared with 2·3% in the group with both high Fe intakes (> reference nutrient intake) and high vitamin C intakes (> median). Anaemia was three times more common in vegetarians than omnivores (25 v. 9%), and in girls who had tried to lose weight in the last year compared with those who had not (23 v. 7%). The questionnaire did not prove satisfactory as a screening tool for risk of Fe deficiency. The higher-than-expected prevalence of Fe deficiency in apparently healthy white girls suggests that other groups should also be investigated.

The effects of bran and starchy endosperm fractions of oat and rye on faecal weight and on biliary and faecal bile acids were studied in Syrian golden hamsters (Mesocricetus auratus). The animals fed on diets supplemented with steam-flaked oat bran, oat bran or rye bran had higher wet and dry weights of faeces compared with the animals fed on the fibre-free or low-fibre endosperm diets. A higher mean percentage of biliary cholic acid and a lower mean percentage of chenodeoxycholie and lithocholic (LCA) acids was observed in the bran-supplemented dietary groups. Animals fed on the bran-supplemented diets had increased daily faecal excretion of both total saponifiable and total free bile acids compared with the animals fed on fibre-free or endosperm-supplemented diets. The mean percentage of total saponifiable bile acids in the faeces was higher, and that of free bile acids lower in the animals fed on bran-supplemented diets. A significantly lower concentration of faecal free LCA was observed in the animals fed on the rye-bran diet. Both bran and endosperm diets reduced the faecal LCA: deoxycholic acid compared with the fibre-free diet, but the bran diets had a more pronounced effect than endosperm diets.

The stability of iron ascorbate solutions was investigated, under both anaerobic and aerobic conditions, with the Fe2+ and Fe3+ indicators, respectively ferrozine and mimosine, at different pH values. The species present under the differing conditions were investigated by electron paramagnetic resonance (EPR) and Mössbauer spectroscopy and by gel-filtration chromatography. At physiological pH (6·8–7·4) iron ascorbate solutions rapidly form mononuclear chelatable Fe3+ species as reflected by indicator studies and EPR. Mössbauer spectroscopy fails to detect any Fe2+ species. EPR studies show a time-dependent decrease in rhombic Fe3+, particularly in oxygenated buffers, consistent with a conversion to polynuclear Fe. O2 uptake studies show that the conversion of Fe2+ to Fe3+ in Fe–ascorbate solutions at pH > 7·0 was accompanied by rapid O2 consumption but preceded depletion of ascorbate. Addition of high concentrations of mannitol (50–200 mM) reduces the O2 consumption and partly stabilizes the rapidly chelatable Fe form. Gel filtration studies show that the oxidation of Fe–ascorbate solutions at pH 7·4 is accompanied by an increase in the apparent relative molecular mass of the Fe, presumably due to Fe polymer formation. These studies indicate the inherent instability of Fe–ascorbate solutions above neutral pH and clearly have important implications in the use of ascorbate in studies of Fe physiology.

The effect of dietary fructose v. glucose on Fe solubility in the small intestine and apparent Fe absorption was studied in rats. Female rats were fed for 4 weeks on low-Fe (10 mg Fe/kg) or normal-Fe (40 mg Fe/kg) diets containing either fructose or glucose (709·4 g monosaccharide/kg). Fe was added to the diets in the form of FeSO4. The low-Fe diets did not lower levels of haemoglobin and packed cell volume, but significantly lowered Fe concentration and Fe mass in the liver, kidney and spleen. Fructose v. glucose also lowered Fe concentrations in these organs, but did not alter absolute Fe contents. Low Fe intake reduced the amount of Fe in the intestinal lumen. The total amount of Fe and Fe concentration in the liquid phase of the proximal intestinal lumen were depressed by fructose irrespective of Fe intake. Fructose also lowered the amount of Fe in the liquid phase of the distal intestine. In keeping with these observations, dietary fructose significantly lowered apparent absorption of Fe at the two levels of Fe intake. Decreasing the intake of Fe raised the percentage of apparent Fe absorption.

The digestibility of polysaccharides and other major components and the metabolic response of the microflora in the small and large intestines to oat diets varying in mixed linked (β(l →3; 1 →4)-D-glucan β-glucan) were studied in experiments with ileum-cannulated pigs. The oat fractions for diets were prepared in a dry milling process in which oat groats were milled into two endosperm fractions (oat flour 1 and oat flour 2) and oat bran. The digestibility of polysaccharides and the metabolic response of the microflora were followed for the two contrasting diets, oat flour 1 and oat bran, from ingestion to excretion while the digestibility of oat groats and oat flour 2 were estimated only at the ileum and in faeces. There was no degradation of β-glucan from either oat flour 1 or bran in the stomach and the first, middle and distal thirds of the small intestine (average digestibility approximately 0), while in the terminal ileum digestibility increased to 0·30 to 0·17 respectively. The digestion of starch in the first third of the small intestine was lower for the high-β-glucan oat-bran diet (0·49) than for the low-β-glucan flour diet (0·64). However, digestibility differences between the two diets levelled out as the digesta moved aborally in the small intestine and the digestibility at the terminal ileum was almost complete (0·970–0·995) for all diets. Oat non-starch polysaccharides (NSP) were an easily digestible energy source for the microflora in the large intestine less than 13% of dietary NSP being recovered in faeces. The bulk of β-glucan which survived the small intestine was degraded in the caecum and proximal colon while arabinoxylan was more slowly degraded. The amount of residues passing the ileo-caecal junction has little impact on the density of micro-organisms in the large intestine, which on the flour and bran diets were in the range of 1010–1011 viable counts/g digesta, but a high impact on the activity of the flora in colon. Oat bran resulted in a higher proportion of butyric acid in large intestinal content compared with the flour diet. The faecal bulking effect of oat bran was mainly caused by an increased excretion of protein and fat, presumably of bacterial origin. Of all the diets tested the oat-bran diets had the lowest digestibilities of protein and fat at the terminal ileum and in the faeces.

Physico-chemical properties of dietary fibres might be involved in metabolic control, particularly of the postprandial blood glucose response. The aim of the present study was to look at the effects of the content of soluble fibres and of the particle size of solid fibres on in vitro and in vivo starch hydrolysis and on the subsequent glucose absorption as well as the triacylglycerolaemia. Two sources of dietary fibres, one, with soluble fibres (beet pulp), the other with mostly insoluble fibres (wheat bran), were added at the rate of 60 g/kg to a meal simulating human food. The fibre sources were ground in order to obtain two different particle sizes (250 and 500 μm). Beet pulp decreased significantly (P < 0·05) initial in vitro hydrolysis whereas wheat bran increased starch hydrolysis in the first 10 min. Wheat bran and beet pulp, whatever its particle size, lowered the post-prandial triacylglycerol response. No significant effect was found with dietary fibre-supplemented diets on postprandial glycaemic and insulinaemic values. High correlation was found between initial in vitro starch hydrolysis and mean areas under the insulinaemic curves. This in vitro model can be used to predict initial in vivo digestion of carbohydrates from complex foods.

Pigs (25–45 kg) were fed on either cereal or semi-purified basal diets supplemented with either high or low levels of sugar-beet pulp or wood cellulose (Solka-floc). The apparent digestibility and retention of N and apparent digestibility and metabolizability of energy (GE) and the apparent digestibility of non-starch polysaccharides (NSP) and their constituent monomers were measured during weeks 2, 4 and 6 of the trial. N and GE were less well-digested, retained or metabolized from cereal basal diets than from the corresponding semi-purified diets during all three periods. NSP from sugar-beet pulp was highly digestible, unlike that from Soka-floc which was relatively poorly digested. These differences of NSP digestibility were seen more clearly when incorporated in semi-purified diets. There was no significant increase in the digestibility or retention of N, or digestibility or metabolizability of GE, or in the digestibility of sugar-beet pulp NSP with increasing time-period on the diets. In contrast, the digestibility of Solka-floc NSP tended to increase with the time-period. The digestibility of NSP from the semi-purified diet with the high level of Solka-floc inclusion was much lower than that for the low level of inclusion, indicating that microbial activity had been reduced. In conclusion, adaptation to the diets in terms of N and GE balance may be complete after 1 week, but 3–5 weeks may be necessary before stability of measurements of the digestibility of resistant NSP monomers can be obtained.

The present experiment was designed to test the hypothesis that ageing modifies the gastrointestinal responses to a change in diet composition. Rats of the Wag/Rij strain, either young adult (4 months of age) or elderly (27 months of age), were given a basal semi-purified diet or a diet of similar major nutrient composition containing 500 g oatmeal/kg for 17–18 d. Elderly rats digested the dry matter (DM) and organic matter (OM) of both diets less well than did their young adult counterparts, with more of this digestion occurring in the distal intestine. The greater flow of OM to the caecum of oats-fed animals was accompanied by significant reductions in caecal pH and increases in caecal total short-chain fatty acids (SCFA) concentration which appeared to be independent of age. However, young adults responded to feeding on oats by showing a much larger increase in the molar proportion of butyrate (332%) than did elderly animals (79%). Elderly rats had longer duodenal villi than did young adults but effects of age or diet were not detectable at other sites. With both age-groups oats consumption was associated with significant stimulation of crypt cell proliferation rate (CCPR) in the small intestine and caecum, but for the colon there was a significant reduction in CCPR with oats feeding. A reduced ability of the aged large bowel (LB) to produce butyrate may contribute to the prevelance of LB disorders in the elderly.

The aim of the present study was to assess the relationship between the disappearance of dietary fibre sugars and the production of individual short-chain fatty acids (SCFA). The bacterial degradation of five dietary fibres whose sugars were quantified was investigated in vitro using a human faecal inoculum. Involvement of the main fibre sugars in SCFA production was evaluated by a stepwise multiple linear regression. The results show first that the nature and chiefly the associations between the fibre sugars were key variables in the fermentability. Second, the nature and the amounts of SCFA produced were closely related to the in vitro fermentation of the main sugars available: uronic acids seemed to be principally involved in the production of acetic acid whereas the production of propionic acid could be promoted by the fermentation of glucose and, to a lesser extent, by that of xylose and arabinose. Xylose tended to have a greater impact than uronic acids and glucose on the production of butyric acid. Thus, it would be possible to predict which SCFA could be specifically produced during the fermentation of a fibre, as far as the chemical composition and structure of this fibre are known.

The hypothesis tested was that Zn deficiency aggravates impaired thyroid function as induced by I deficiency. In two separate experiments male rats were fed on diets either deficient in Zn or in I, or deficient in both. An identical, restricted amount of food was given to each rat so that body-weight gain of the experimental groups was comparable. Zn deficiency was evidenced by reduced tibial Zn concentrations. I deficiency was evidenced by goitre, reduced urinary I excretion, reduced plasma thyroxine concentrations and reduced absolute amounts and concentrations of thyroxine in the thyroid. Zn deficiency had no effect on the raised thyroid weight as induced by I deficiency. Zn restriction from 184 μmol Zn/kg diet to 31 μmol Zn/kg diet, hut not to 92 μmol Zn/kg diet, significantly lowered plasma thyroxine concentration. There were no interrelated effects of Zn and I deficiencies on thyroid hormone levels. These results indicate that marginal Zn deficiency does not influence thyroid hormone metabolism in I deficiency.

Sucrose feeding over a long period has been reported to induce glomerular basement membrane (GBM) thickening and insulin resistance in normal rats. These effects are attributed to the fructose moiety of the sucrose molecule, to Cu deprivation or both. Consequently, our aim was to evaluate the long-term effects of fructose feeding with normal or high amounts of Cu on body weight, plasma lipids, blood glucose regulation, GBM thickening and insulin binding to adipocytes. Four groups of eight Sprague–Dawley rats were fed for 10 weeks on a diet containing 570 g carbohydrate/kg supplied either as starch (S), dextrose (D), fructose (F) or fructose–starch (1:1, w/w; FS), and an adequate amount of Cu (12 μg Cu/g diet). A fifth group was fed on diet F supplemented with 24 μg Cu/g diet (FCu). After 10 weeks the epididymal adipose tissue and kidney weights expressed per 100 g body weight (relative weight) were heaviest in the F and FCu groups (P < 0·0001, ANOVA). The GBM thickness was within the normal range in the five groups but significantly higher in group D (1·95 (SE 0·04)) nm and lower in group FS (1·79 (SE 0·02)) nm when compared with group S (1·85 (SE 0·03) nm; P < 0·05). Insulin binding to adipocytes (expressed per cell) was lowest in the F and FCu groups, intermediate in groups D and FS and highest in group S (P < 0·05). Fasting plasma insulin level was higher in group F than in the FCu and FS groups (P < 0·05), whereas fasting plasma glucose, total cholesterol and triacylglycerol levels remained within the normal range in all groups. We conclude that in normal rats a 10-week fructose-rich diet with an adequate amount of Cu produced deleterious metabolic effects on adipose tissue, insulin binding to adipocytes, and plasma insulin, but not on GBM thickening even though kidney weight was significantly increased. However, a moderate fructose intake mixed with other sugars did not have adverse effects.