1. The fermentative breakdown of dietary fibre from various sources in the intestinal tract was studied using rat balance experiments and gas–liquid chromatrographic analysis of dietary fibre monomers in feed and faeces.

2. On a basal diet with 690 g maize starch/kg but no added fibre, small but detectableamounts of polymeric glucose, rhamnose, arabinose, xylose, galactose, mannose and uronic acids, i.e. sugars occurring in dietary fibre, were excreted in faeces.

3. Dietary fibre in wheat bran was rather resistant to fermentation; 63% was recoveredin the faeces. Guar gum, on the other hand, was almost completely fermented, whereas 19 and 25% of the uronic acids in low and high methoxylated pectin respectively, were excreted in faeces. The various constituents of sugar-beet dietary fibre (approximately equal amounts of arabinose-based hemicellulose, pectin and non-starch glucan (cellulose)) showedquite variable availability for micro-organisms in that 6–12% of the arabinose, 17–25% of the uronic acids, and 52–58% of the cellulose were recovered in the faeces.

4. Faecal nitrogen excretion increased on addition of any one of the dietary fibre preparations studied, resulting in decreased true and apparent protein digestibility values.

5. The faecal dry weight increment was most pronounced when feeding bran and could then almost be accounted for by the remaining fibre and by protein. The less-prominent bulking effect ot guar gum and pectins, that were much more extensively fermented, could be only partly explained by dietary fibre and protein.

1. An unsupplemented 4200 kJ (1000 kcal) diet emphasizing large quantities of relatively unrefined complex carbohydrates was evaluated among sixty obese adults for its effectiveness and nutritional adequacy in a long-term weight-control programme. Patients were followed individually as outpatients by a physician and dietician–an average of thirteen visits over 26 weeks. Assessment of health indices included anthropometric measurements, blood pressure, lipid levels and assays for seven vitamins, β–carotene and iron.

2. Weight loss averaged 8.2 kg or 24% of excess weight during the 6 months of active treatment. Over an average of 17 months of post-treatment follow-up, 44% of patients continued to lose weight and 92% remained below pretreatment levels.

3. Average skinfold thickness fell 7mm (p < 0·001) whereas muscle mass was maintained (arm muscle circumference+10mm, not significant; creatinine-height index + 3% of standard (Bistrian et al. 1975; not significant). Systolic and diastolic bleed pressure fell 7 and 5 mmHg respectively (P < 0·01). Total serum cholesterol and triglyceridesfell 200 and 660 mg/1 respectively (P < 0·01), while high-density-lipoprotein-cholesterol remained statistically unchanged. Mean serum levels of retinol, β-carotene, folate, vitamin B12, ascorbic acid, Fe and transferrin saturation, and activity coefficients for thiamin, riboflavin and pyridoxine were within normal limits after periods of treatment ranging from 5 to 84 weeks.

4. An earlier age of onset of obesity tended to be associated with greater weight lossduring treatment and lesser weight rebound during follow-up.

5. The results indicate that the experimental diet, without supplementation, was nutritionally adequate as well as effective for long-term weight control.

1. The amounts of iodine in nationally representative samples of prepared and cooked groups of foods and in a wide variety of individual foods and food products were determined colorimetrically. The amounts of erythrosine, a red food colour containing 577 mg I/g were also determined in selected foods and diets by high-performance liquid chromalography.

2. The average British diet was calculated to provide 323 μg I/d but only 255 μg if two fruit samples containing large amounts of glacé cherries were discounted. Of the total, 92 μg was derived from liquid milk. Meat and meat products provided 36 μgand cereal products 31 μg, but fresh fruitsand sugars, vegetables and beverages provided little I. Fish and fish products, though rich in I, contributed only 5% to the total intake.

3. Milk was the most variable as well as the most important individual source of I. Summer milk samples contained 70 μg/kg and winter milk 370 μkg on average. Milk products, including butter and cheese, and eggs were also rich in I.

4. Some processed foods contained erythrosine, particularly glacé cherries and some pink or red confectionery items, biscuits, cherry cake, canned strawberries and luncheon meat. However, none of these are major foods in the average household diet and erythrosine would therefore contribute little more than 10 μg I/d to most diets.

5. The average daily intake of I was lower than in similar studies in the USA, but wastwice the provisional UK recommended intake. This study provides no evidence that I intakes in the UK could be too low or loo high for health.

1. The hepatic uptake of indocyanine green (ICG) has been measured in rats receiving a 50 g protein/kg diet for 6, 12 or 20 d or a choline-deficient diet for 2 or 6 d.

2. There was no effect on ICG uptake on the choline-deficient diet, although all the rats developed an intense fatty infiltration of the liver by 6 d.

3. The rats on the 50 g protein/kg diet showed impaired uptake of ICG at 6, 12 and 20 d, which appeared to be related to the extent of fatty infiltration.

4. It is concluded that ICG uptake is predominantly a function of the periportal zone of the liver lobule, and therefore likely to be sensitive to insults that exert their predominant effect in this zone.

1. People with an ileostomy experience digestive problems with some foods. Why these foods are avoided is not known nor is it certain whether this interferes with the nutritional adequacy of their diet.

2. A detailed dietary assessment has therefore been made of thirty-seven subjects with ileostomies and a similar number of age-and sex-matched healthy controls. All food and drink eaten over 1 week was weighed and recorded. In addition, a larger group of seventy-nine ileostomy subjects and seventy matched controls answered a questionnaire designed to identify foods which upset them and which they avoided.

3. Total nutrient and energy intakes were similar in the two groups but the subjects with an ileostomy ate less dietary fibre (g/d; mean ± SD: ileostomy subjects 18·0±5·9, controls 20·9±5·5; P < 0·05) mainly due to lower fruit and vegetable intakes. Iron and vitamins A and C intakes were also less.

4. A majority of ileostomy subjects had a pattern of food intake different from the controls, taking more of their energy in the morning and less at night. A variety of food items upset more than half of them including nuts, pips, seeds, skins, onions, beetroot, lettuce, raw cabbage and carrot, peas, sweetcorn, mushrooms and dried fruit.

5. On the basis of the results it is possible to formulate general dietary advice for people with an ileostomy.

1. Most subjects who have their large intestine removed and an ileostomy formed lead a healthy life after operation, although they are prone to a variety of metabolic problems. In order to determine the factors likely to lead to these metabolic disturbances a detailed assessment of ileostomy output and composition and of dietary intake in relation to nutritional and metabolic status has been made in a group of ileostomy patients living at home.

2. Thirty-six volunteers with established ileostomies (twenty-six ulcerative colitis (UC) patients and ten, Crohn's colitis (CC) patients) made a 24 h collection of urine and ileostomy effluent and kept a 7 d record of dietary intake and the frequency with which they emptied their ileostomy bag. Blood was collected for haematological and biochemical indices of nutritional status and height, weight and skinfold thickness were measured.

3. Effluent output for the whole group was 760±322 g/day (range 273–1612) and was very closely related to effluent sodium output (R 0·98). Stepwise multiple regression analysis of dietary and other variables identified the amount of ileum resected as the main determinant of both effluent output and effluent sodium. The CC group had significantly greater effluent output (1084±340 g/d) compared with the UC patients (635±215g/d) (P < 0·001); and excreted significantly more nitrogen, carbohydrate and sodium than the UC group.

4. The CC patients particularly showed evidence of salt depletion. The mean (±SD) 24 h urine Na loss for CC patients was 31±30 mmol and for UC patients 67±34 mmol (P < 0·01) with five of the ten CC patients v. four of the twenty-six patients with UC having raised urinary or plasma aldosterone levels.

5. All subjects had normal haematological and biochemical indices of nutritional status in the blood. Height and percentage body fat were also within the normal range when compared with a control population matched for age, sex and occupation, but patients with an ileostomy weighed on average 4·1 kg less than the controls.

6. These studies show that patients with an ileostomy come within the range of the normal population for most nutritional indices although are at increased risk of salt depletion. Effluent volume, which is probably the determining factor in most metabolic complications of ileostomy, is related more to the extent of the small bowel resection than to diet.

1. Male rats were undernourished either during the geslational and suckling periods or for a period of time immediately following weaning. Some rats were killed at the end of the period of undernutrition; others were nutritionally rehabilitated for lengthy periods of time before examination. Two muscles, the extensor digitorum longus (EDL) and soleus (SOL) were studied from each rat. Histochemically-stained transverse sections of these muscles were used to determine total number of fibres, the fibre cross-sectional areas and the relative frequency of the various fibre types.

2. All rats killed immediately following undernutrition showed significant deficit sin body-weight, muscle weight and fibre cross-sectional area compared to age-matched controls.

3. Animals undernourished during gestation and suckling and then fed normally for 5 months showed persistent and significant deficits in body-weight, muscle weight and total fibre number. There were also significant deficits in mean fibre cross-sectional area of each fibre type except for red fibres in the EDL. No difference in the volume proportion of connective tissue was found.

4. Rats undernourished after weaning and then fed ad lib. for approximately 7 months had normal body-and muscle weights. Their muscles showed no significant differences in total fibre number, relative frequency of the various fibre types, fibre size or volume proportion of connective lissue.

5. These results indicate that, although the effects on rat skeletal muscle of a period of undernutrition after weaning can be rectified, undernutrition before weaning causes lasting deficits.

1. The contractile properties of soleus and extensor digitorum longus muscles from animals at 12 months of age whose mothers had been undernourished during pregnancy and lactation (PU rats) have been compared with those of muscles from age-matched controls.

2. Body-weight and muscle wet weight of PU rats was significantly reduced. Muscle: body-weight values were, however, no different from controls.

3. No significant alterations in whole muscle speeds of contraction or relaxation could be delected when compared with those of age-matched controls.

4. Twitch and tetanic forces of both SOL and EDL were greater per unit weight of muscle in PU rats. Apart from SOL twitch these differences were significant. The tetanus:twitch values were, however, not different.

1. A detailed investigation was made of the motor performance of rats which had impaired cerebellar and muscular growth resulting from early-life undernutrition.

2. Developing rats were growth-retarded by underfeeding their mothers during pregnancy and lactation. They were fed ad lib. from 25 d of age.

3. Adult male previously-undernourished (PU) and well-fed control rats were given tests of motor behaviour commencing at 5 months of age. They were required to run backwards to maintain their position on a revolving drum. Aspects of the test situation were varied systematically: visual environment, interval between trials, test duration and drum speed.

4. PU rats had a 29% body-weight deficit compared with controls at 5 months.

5. There was no evidence of impaired motor performance by the PU rats under any of the test conditions.

1. Utilizing the bromodeoxyuridine differential-chromatid labelling technique the in vitro proliferation of lymphocytes from children with kwashiorkor was followed in phytohaemagglutinin-stimulated cultures and compared with controls.

2. Analyses of first, second and third or subsequent division cells as a function of culture time between 40 and 96 h showed that cell-cycle duration was prolonged in kwashiorkor cultures. The extent of this increase was approximately 4.5 h for the first-division cells and 1.5 h for third-division cells.

3. The peak for second-division cells was depressed in kwashiorkor cultures.

4. A decreased number of third or subsequent-division cells was observed in kwashiorkor cultures at all time points studied.

5. These findings suggest that the loss in lymphocyte activity to PHA in malnourished children in general could be due to an increase in cell-cycle duration of responding lymphocytes.

1. Twelve young adult male volunteers were given a low-fibre white bread diet (9 g neutral-detergent fibre (NDF)/d) and a medium-fibre coarse-bran bread diet (22 g NDF/d), each lasting 20 d. In a third period of 20 d the volunteers were subdivided in groups of four, consuming a high-fibre coarse-bran bread diet (35 g NDF/d). a medium-fibre fine-bran bread diet (22 g NDF/d, bran particle size < 0.35 mm) or a wholemeal bread diet (22 g NDF/d), Retention of calcium, magnesium, iron, zinc and copper were determined during each 20 d period.

2. An increase of the amount of dietary fibre (through bran in bread) from 9 g to 22 g NDF/d resulted in a significantly increased mineral intake, but also faecal excretion increased significantly; mineral retention remained almost constant.

3. Both intake and faecal excretion of all minerals studied, except faecal Ca. increased further (P < 0.05) on the diet providing 35 g NDF/d: only Fe balance decreased significantly. No significant differences with respect to intake, excretion (except urinary Ca) and balance of the minerals could be detected between the coarse-bran bread and fine-bran bread diets providing 22 g NDF/d. Faecal Fe, Cu balance and Mg balance increased significantly during the wholemeal bread period compared to the coarse-bran bread diet providing 22 g NDF.

4. Serum cholesterol increased significantly, i.e. by 0.3 mmol/1, during the coarse-bran bread diet providing 22 g NDF, compared to the white-bread diet.

5. It is concluded that increasing the amount of bran in bread does not appear to affect mineral balance considerably but there seems to be an influence on mineral availability. The increased intake was accompanied by increased faecal excretion.

1. The effects of feeding a palatable and varied ‘cafeteria’ diet on energy balance were studied in young (5·5 week) and adult (5·5 month) lean male Zucker (+/?) rats.

2. Estimates of metabolizable energy (ME) intake derived from food composition tables were almost identical to values obtained from bomb calorimetry of foods, urine and faeces, and ME intake was elevated by approximately 73% in all ‘cafeteria’ animals compared to stock-fed controls.

3. ‘Cafeteria’ feeding had no effect on the body-weight of young rats but induced excess weight gains in the older animals and resulted in increased deposition of fat and energy in both groups. Energy expenditure, calculated from ME intake and body-energy gain, was elevated by 77 and 57% in young and adult cafeteria rats respectively. The energy cost of fat deposition could account for only a small proportion of this increased expenditure.

4. The present results confirm previous findings in another strain of rat and show that the increased energy expenditure (i.e. diet-induced thermogenesis, DIT) which occurs in response to hyperphagia is not restricted to young animals but is also seen in older rats. Measurements of resting oxygen consumption after injections of noradrenaline or a β-adrenergic antagonist (propranolol), and changes in brown adipose tissue mass are consistent with the suggestion that the DIT of ‘cafeteria’-fed rats results from sympathetic activation of brown fat.

1. A study was undertaken to investigate the distribution of ascorbic acid between various cellular components of blood, in normal individuals, and its relation to the plasma concentration. Forty-one unsupplemented individuals and sixteen supplemented (2 g/d for 5 d) individuals were studied.

2. Granulocytes, mononuclear leucocytes, platelets and erythrocytes were separated by differential sedimentation and centrifugation. Ascorbic acid contents were measured by the dinitrophenylhydrazine method.

3. Ascorbic acid content per cel was higher in mononuclear leucocytes and granulocytes than in platelets and erythrocytes. Intracellular ascorbic acid concentrations, calculated from published values for cell volumes, when compared with the plasma concentration showed a marked ability to concentrate ascorbic acid in mononuclear leucocytes (80 times), platelets (40 times) and granulocytes (25 times).

4. Erythrocytes showed little ability to concentrate ascorbic acid over the normal range of plasma concentration but because of their relative numbers they and the plasma fraction accounted for most of the blood-borne ascorbic acid (> 70%).

5. The ascorbic acid content of granulocytes, platelets and erylhrocytes showed a significant positive correlation with the plasma concentration and supplementation with ascorbic acid significantly increased the content of these cell types. Mononuclear leucocytes in contrast did not show any such relationship.

6. The ability of the mononuclear leucocytes to maintain the highest levels of ascorbic acid in the cell types studied, despite variation in plasma availability, warrants further study, particularly in view of the importance of these cells in immunocompetence.

1. Patients with cataract were classified into undernourished (twenty-eight subjects) and well-nourished (twenty-seven subjects) groups based on the anthropomtric index, weight (kg)/height (m)2. Those with a value for the index of less than 18 were considered as undernourished.

2. Lenses were classified into four groups on the basis of nuclear colour as proposed by Pirie (1968). Lenses of pale uniform colour or yellow colour were included in group 1, those with brownish-yellow nucleus in group 2, those with a yellowish-brown nucleus in group 3 and those with brown nucleus in group 4.

3. Irrespective of group, the wet weight, dry weight, percentage moisture and total protein content of cataractous lenses from undernourished patients were similar, as were the corresponding values for well-nourished patients. On the other hand, the percentage of soluble proteins in lenses tended to decrease with deepening of nuclear colour in both groups of patients. Further, soluble protein concentrations in lenses from undernourished patients were significantly lower as compared to those from well-nourished patients.

4. The results suggest that nutritional factors could influence the composition of cataractous lenses.

1. Plasma total cholesterol, high-density-lipoprotein (HDL)-cholesterol total protein, albumin and globulin levels were estimated in blood samples from thirty children with kwashiorkor, thirty-five with marasmus, twenty-eight with marasmic-kwashiorkor and twenty-seven control children.

2. HDL-cholesterol was estimated after the very-low-density and low-density lipoproteins were precipitated from the plasma with heparin and manganese chloride.

3. The distribution of HDL-cholesterol in the control and in the children with PEM was skewed and the range of values was wide. The values were independent of age and sex.

4. After logarithmic transformation of the HDL-cholesterol and HDL-cholesterol: total cholesterol values, the geometric mean values for the three groups of children with PEM were significantly decreased when compared with values for the control children.

5. The decrease in the mean HDL-cholesterol value for the children with kwashiorkor was more than for children with marasmus and marasmic-kwashiorkor.

1. Although disrupted parturition and high foetal losses have previously been reported in pregnant rats maintained on zinc-deficient diets this is the first report to differentiate between the effects of reduced Zn intake and the effects of reduced food intake on theoutcome of pregnancy in the rat.

2. Rats maintained on a 0·5 mg Zn/kg diet for the last 7 d of gestation or on a 5 mg Zn/kg diet throughout gestation did not consume significantly less food than rats given 10 or 20 mg Zn/kg diets except during the last 2 d of gestation. Pair-feeding of Zn-adequate rats (20 mg/kg) to those given low-Zn diets for the last 2 d of gestation did not affect the outcome of pregnancy in these rats.

3. In the rats maintained throughout gestation on 5 mg Zn/kg or on 0·5 mg Zn/kg in the last 7 d of gestation, parturition onset and duration were not significantly altered. Foetal rvival was very significantly reduced but only from day 22 onwards; before the onset of parturition, foetal survival was not significantly affected by Zn deficiency during gestation.

4. Subcutaneous injection of evening primrose (Oenothera biennis) oil into rats throughout gestation enhanced foetal and neonatal survival in rats given 5 mg Zn/kg but reduced foetal survival in rats given 0·5 mg Zn/kg in the last 7 d of gestation.

5. The results suggest three points: (1) subtotal Zn deficiency during gestation in the rat jeopardises foetal survival at parturition without affecting the onset or duration of parturition, (2) foetal death in rats maintained on Zn-deficient diets occurs only in relation to parturition itself, (3) provided that Zn intake near term is at least 5 mg/kg, supplemental essential fatty acids (evening primrose oil) will reduce foetal mortality during parturition and in the neonatal period.

1. Rats were given a purified folate-deficient diet containing 5 g succinylsulphathiazole/kg for 4–5 months in two experiments. Control rats were supplemented with folic acid in the drinking-water.

2. Weight gain was much below normal in the folate-deprived rats after the first month. Very low folate levels were recorded in blood, liver and peripheral nerve (12–33% of control). In Ihe central nervous system, including the cerebrospinal fluid, the folate depletion was less conspicuous (50–80% of control). Only marginal signs of anaemia were found and no signs of neurological dysfunction were detected, using nerve conduction velocity measurement and co-ordination tests.

3. Light and electron microscopy of the folate deficient liver revealed fatty infiltration, and enlargement of liver parenchymal cells, nuclei and nucleoli. There was often a considerable amount of bile ductular cells in the lobuli but no cirrhosis. The morphological changes resembled those observed in choline deficiency.

4. Phospholipid N-methylation in liver was depressed in folate deficiency. This was probably due to a decreased availability of S-adenosylmethionine caused by the low concentrations of methylated folate in liver. Intraperitoneal administration of methionine did not normalize phospholipid methylation.

5. In folate deficiency the proportion of ethanolamine phosphoglyceride in liver was increased at the expense of choline phosphoglyceride, which is consistent with a decreased phospholipid methylation. Also an increase in liver triacylglycerol was noted, in accordance with the morphological observations. Brain lipid composition was unchanged.

6. After the injection of labelled ethanolamine, isotope accumulated in liver phosphoethanolamine in folate deficiency, probably due to an impairment of the CTP: ethanolaminephosphate cytidylyltransferase(EC 2.7.7.14) reaction. The mechanism of this impairment is discussed.

7. Although the low concentrations of folate was the main nutritional change in the deprived animals, changes with respect to vitamin B12 and maybe also choline cannot be excluded. We conclude that some of the changes in folate deficiency, i.e. fatty liver and decreased biosynthesis of liver phospholipids may be due to a precipitated deficiency of lipotropic agents, whereas other differences may be specific for deficiency of folate per se, such as changes in liver phospholipid fatty acids and some of the morphological aberrations.

1. Three diets of barley–canula-seed (Brassica campestiris), lucerne (Medicago sativa) or chopped brome-grass (Bromus inermis) were given at intervals of 3 h to closely-shorn Suffolk wethers held at a temperature of 1–5° (cold) or 22–24° (warm). Apparent digestibility of organic matter (OM) and nitrogen was reduced by 0·08–0·05 and 0·04 units respectively for lucerne and brome-grass diets given to cold-exposed sheep, but no treatment effects on digestibility were observed for the barley–CSM diet. Measurements achieved using infusion of the digesta markers 58Co-EDTA and 103Ru-phenanthroline (103Ru-P) showed that cold exposure depressed apparent OM digestion in the stomach and intestines by 33 and 42 g/d for the lucerne diet, and 13 and 35 g/d for the brome-grass diet respectively.

2. The turnover time (h) of the l03Ru-P marker in the rumen of warm sheep was 38·9 for barley–CSM, 18·4 for lucerne, and 15·6 for brome-grass. In cold-exposed sheep, 103Ru-P turnover time (h) tended to be reduced to 32·3, 12·3 and 15·3 for the three diets, respectively. OM fermentation in the stomach was highly related to 103Ru-P turnover time for lucerne and brome-grass diets.

3. Cold exposure increased the escape of dietary N from the abomasum by 0·04 and 0·09 of dietary N intake for sheep given lucerne and brome-grass diets respectively. Dietary N degradation was closely related to 103Ru-P turnover time for lucerne, and to the proportion of large particles in rumen digesta for the brome-grass diet. Estimates of feed N degradation made by use of information on the rate of fermentation of the diet in nylon bags and 103Ru-P turnover time were consistently lower than those observed in vivo for barley–CSM and lucerne diets. Intestinal digestibility of non-ammonia N was not significantly changed by cold exposure.

4. Transfer of urea from plasma to the rumen was 1·4–2·5 g N/d for the barley–CSM and lucerne diets, but the value for brome-grass was 4·5–4·9 g N/d. Cold exposure did not affect urea transfer. The production of ammonia from feed and endogenous protein was approximately 0·66 and 0·47 g N/g N intake of barley–CSM and lucerne diets, with no effect of cold exposure. Cold exposure reduced the value from 0·57 to 0·38 for brome-grass.

5. The results are compared with those obtained previously with pelleted hay, and the importance of large particle breakdown in the prediction of OM and N fermentation using nylon bags is discussed.

1. A‘new’carbon radioisotope, 11C, for use in nutritional studies is presented. It has a 20 min half-life, and decays by positron emission giving annihilation photons of 511 keV energy (Wolf & Redvanly. 1977). Thus repeated studies can be made with short time intervals and the distribution of radioactivity in the experimental animal can be detected externally.

2. 11C was produced with a tandem Van de Graaff accelerator and L-[Me-11C]methionine was synthesized and used in model experiments in the pig. The tracer wasadministered intravenously through a catheter in the jugular vein of pigs weighing between 40 and 100 kg. In a series of experiments, one pig received a low-melhionine diet supplemented with DL-methionine to give three different levels of methioninc intake.

3. The radioactivity distribution between liver and muscle was measured as a function of time by external detectors for 2–3 h after administration. Blood and exhaled CO2 were sampled and measured for radioactivity.

4. The results indicate that 11C is a useful radionuclide in nutritional studies in intact large domestic animals.