1. Sixteen Indian schoolboys, aged 12–14 years resident in Singapore, were tested for the determination of energy cost, pulmonary ventilation (PV) and oxygen consumption at rest and at various daily activities; their height, body-weight, pulse and blood pressure were also measured. An energy balance study was made by estimating from a diary of measured activities the 24 h energy intake and output.

2. PV and O2 consumption during running showed positive correlations(r = 0.4 and r =0.3 respectively) with mean post-exercise recovery pulse, O2 consumption and PV.

3. The daily mean calorie intake and output of the subjects were found to be 2108 kcal (8.85 MJ) and 1811 kcal (7.60 MJ) respectively.

4. The boys gained an average of 2.2 kg in weight and 0.7 cm in height in 2 months. They did not suffer from any mental retardation, they were physically fit, free from disease and did their daily routine work satisfactorily.

1. Yudkin's (1967) questionnaire on the dietary intake of sugar was given to 415 businessmen for self-administration.

1. The results showed an inverse relationship between sugar intake and relative weight (actual weight as a percentage of expected weight for height and age) and additional evidence suggests a direct relationship between sugar intake and adequate exercise.

2. The statement that ‘sugar was restricted’ was shown to be a factor of considerable importance affecting the reported level of sugar intake and should be taken into account when comparing different series.

3. The positive association between cigarette smoking and mean sugar consumption in this series was due to the low-sugar intake of ex-smokers.

4. In future studies on the role of sucrose in the aetiology of ischaemic disease, both smoking habits and levels of activity should be recorded.

1. The amounts of available cystine and tyrosine in the protein of different animal tissues showed a close correlation with the level of hydroxyproline, and may be estimated from hydroxyproline values by regression equations.

2. Estimates of ‘chemical score’ have been calculated from the content of hydroxyproline determined in a series of samples for which net protein utilization (NPU) for rats had also been determined. Chemical scores calculated as percentages of the total ‘essential+semiessential’ amino acid content of each material correlated closely with NPU, whereas scores calculated as percentages of total amino acids did not. ‘Methionine+cystine’ were calculated to be first limiting amino acids in every sample.

1. Liver composition and hepatic nutrient stores in foetuses born to mothers belonging to a low socio-economic group of the population were determined.

2. The contribution by the liver to body-weight and the concentration of water and nitrogen in liver at different gestational ages were relatively constant.

3. Total iron and copper contents of the liver were in the normal reported range but the ferritin content was considerably lower in the present investigation.

4. Hepatic stores of vitamin A, vitamin B12 and folate were lower than the values that have been reported elsewhere.

5. It is suggested that inadequate stores of iron, vitamin A, vitamin B12 and folate in these infants may predispose them to the early development of some deficiency diesease.

1. The body composition was determined of forty-one fetuses of different gestational ages born to mothers belonging to a low socio-economic group of the population.

2. With increasing gestational age the water content fell from 88% at 28 weeks to 76% at term; the fat content increased from 2.1% to 11.2% and the protein content increased from 6.9 to 9.3%.

3. The changes in body composition were more closely related to body-weight than to gestational age.

4. The calcium, Phosphorus and magnesium contents of the body per unit fat-free weight progressively increased with gestational age, and at term the values appeared to be considerably lower than those reported in the literature. The Ca:P ratio was constant at different body-weights.

5. The body iron content per unit of fat-free weight increased marginally with increasing gestational age. The value was almost 30% lower than the values reported from elsewhere.

6. It is suggested that chemical composition and nutrient stores of the developing foetus can be considerably influenced by the state of maternal nutrition.

1. Measurements of the concentrations of amino acids in the plasma of blood from the portal vein and hepatic vein in the livers of rats made diabetic with streptozotocin or alloxan and starved for 1 d were compared with similar measurements from normal rats starved for 1 d.

2. The concentrations of many of the amino acids in the blood plasma were lower in the streptozotocin diabetic rats than in the normal animal while the liver concentrations tended to be increased. This suggests that there is enhanced concentration of these amino acids by the liver in diabetics, as is also found in starvation, which is probably due to factors other than the direct absence of insulin.

3. The direction of flow of the groups of amino acids into and out of the liver was unchanged in the diabetic compared with the normal rat except that the output of tryptophan was abolished, and that of the branched-chain group was abolished in alloxan diabetes though apparently enhanced in streptozotocin diabetes. The rates of movement of amino acids in both directions appeared to be increased in the streptozotocin diabetic animals.

4. The changed amino acid pattern in the alloxan diabetic rats was to some extent similar to that of the streptozotocin diabetic rats but the changes were more difficult to interpret, perhaps because of side-effects of alloxan on tissues including liver.

1. Energy, protein, fat and iron have been determined by chemical analysis in a number of meals and whole days' diets prepared by large-scale catering methods. The results have been compared with the results of calculation from food composition tables.

2. There were wide differencesbetween calculated and analytical values for all the constituents, especially for fat and iron. For energy and fat, calculation from food tables gave constantly higher results than did analysis.

3. Large differences in calculated and analysed fat and energy intakes occurred especially when there was frequent use of certain foods that are generally prepared in a non-standard way.

4. The range of differences between average calculated and analytical results depended on the duration of surveys. We have estimated that in a 7 d survey, calculated 7 d protein and energy intakes would fall within ± 20% of the analytical value in 90% of individuals; for iron and probably for other minerals, the range would be ± 50% of the analytical value.

1. Energy expenditure determinations have been made on thirty-two soldiers newly arrived in the warm humid climate of southern Malaya. Ergometer cycling was investigated as well as everyday activities such as lying, sitting, riding in a trunck, abultions, buildings a jungle camp and walking with loads over four different routes.

2. The inter-individual variation in the gross energy expenditure (kcal/min and kJ/min) of each activity has been compared with the variation in energy expenditure standardized for body-weight, surface area and lean body mass. Standardization for body size did not consistently or effectively reduce the coefficients of variation of energy expenditure.

3. The gross energy expenditure of most activities was significantly correlated with bodyweight, surface area or lean body mass but the correlation coefficients were not of a high order, suggesting that less than 41% of the inter-individual variation in energy expenditure was accounted for by variation in body size.

4. The energy expenditure of walking at various speeds over both firm and uneven terrain was related to the square of the walking speed and the total weight of the man and his equipment (correlation coefficients 0.89–0.92, P < 0.001).

1. Rats were given stock chow diets containing several levels of calcium cyclamate to study the effects on growth and on some metabolites in liver and blood.

2. Levels up to 1% in the diet produced diarrhoea without affecting body-weight. At a level of 3% in the diet, body-weight was decreased by 12% in 8 weeks.

3. No changes were noted in liver protein, lipid and RNA-P and serum protein and lipid. 14CO2 excretion during the 1st hour after [14C]glucose administration also remained unchanged.

4. Adult rats weighing 500 g were given, at a restricted intake, a diet with variations in its fat and cyclamate contents.

5. During 15 weeks, the animals given the fat-supplemented diet plus cyclamate lost twice as much weight as controls without cyclamate and also excreted 20% more 14CO2. When the food intake was further restricted for 15 weeks weight losses in all groups were the same.

6. Serum lipid and free cholesterol concentrations were lowered in the cyclamate group. 14CO2 excretion for this group was 35% higher than for controls, indicating increased metabolic activity.

7. Concentrations of aspartate, glutamate, lactate, succinate, malate and glycerol-I-phosphate in liver were within normal limits. There were indications of decreased levels of lactate and succinate in cyclamate-fed rats which could be associated with aerobiosis and increased metabolic activity.

1. Fatty acid levels were studied in the tissues of 1-week-old calves receiving maize oil (in filled milk) with and without supplementary α-tocopherol. The calves that were not given vitamin E developed muscular dystrophy.

2. Decreased amounts of linoleic acid and increased amounts of arachidonic acid were found in nearly all the lipid fractions of skeletal muscles, hearts, livers and kidneys of vitamin E-deficient calves. The concentration of the polyunsaturated fatty acids beyond arachidonic acid remained about the same in both groups. There was a significant decrease of 20:2Ω6 fatty acid in the phosphatidy1 choline, phosphatidy1 ethanolamine and free fatty acid fractions in the livers and kidneys of vitamin E-deficient calves.

3. It is suggested that vitamin E has an inhibitory effect on the desaturating but not on the chain-elongation enzymes of microsomes in the liver and kidney.

4. Maize-oil feeding had only a slight effect on erythrocyte fatty acid composition, and the erythrocyte haemolysis test was negative even in the vitamin E-deficient animals.

1. Pre- and post-prandial metabolic rates were measured in twelve malnourished Jamaican infants.

2. On admission to hospital, minimal increase in postprandial metabolic rate were found, whereas during the recovery phase when growth was rapid, inreases in postprandial metabolic rate of up to 38% occurred.

3. After recovery only the five children who were still gaining weight at a rate of more than 4 g/kg body-weigh. d continued to show a substantial increase in postprandial metabolism.

4. A highly significant correlation was found between growth rate and the increase in postprandial metabolic rate.

5. Marked differences existed in the respiratory quotient measured 4 h after the last meal, the values being low on admission and high during the phase of rapid growth.

6. After a test meal, the respiratory quotient rose sharply both innewly admitted and in recovered children, but fell slightly when the children were studied during the phase of rapid growth.

1. The effect of methionine supplementation upon pancreatic trypsin, chymotrypsin, pancreatopeptidase E and amylase of chicks given raw and heated soya-bean diets (RSD and HSD) was studied before and after fasting.

2. Statistical analysis of the ratios of amylase to pancreatopeptidase E, trypsin and chymotrypsin in each individual chick revealed that methionine supplementation consistently increased the ratio of amylolytic to proteolytic enzymes. This phenomenon was most marked in the fasted RSD group, less in the fed RSD and fasted HSD groups and least in the fed HSD group.

3. The results are discussed in relation to methionine metabolism in chicks given RSD and HSD supplemented with trypsin inhibitors.

1. Groups of newborn calves were fed on liquid diets which had fat contents ranging from 0.2 to 17% (dry- weight basis) and which provided linoleic acid in amounts ranging from 0.01 to 0.7% of the calorie intake. Two commercial milk replacers, high in fat (17–18%) and linoleic acid (3.4 and 5.0% of calories) were also given. All diets were given for at least 65 d.

2. Except for reduced feed utilization associated with the two diets lowest in fat (0.2 and 0.4%), the calves developed normally, without signs of essential fatty acid deficiency.

3. The polyunsaturated fatty acid content of erthrocytes and plasma phospholipids and cholesteryl esters rose rapidly during the first few days on all diets. At 65 d, these concentrations were higher than at birth and appeared generally to be related to the linoleic acid intake. However, in the low dietary linoleic acid range, the fat content of the diet also seemed to exert some influnce. In no instance was there any indication of the appearance of 20:3ω9, which is observed in other species under conditions of essential fatty acid deficiency.

4. Some of the experimental diets were given to weanling rats. There was a rapid fall in the polyunsaturated fatty acid content of erythrocyte lipids and plasma phospholipids and cholesteryl esters, accompanied by the appearance of 20:3ω9.

5. These results suggest that calves on liquid diets have apparently a very low requirement for essential fatty acids.

1. Concentrations of the amino acids in the plasma of blood from the portal vein and hepatic vein and in the liver of fed rats and rats starved for 1 d or 3 d were measured. The 1 d values were compared with the equilibrium concentrations of the amino acids found in the perfusion medium during perfusion of livers from rats starved for 1 d.

2. The measurements of portal–venous differences in amino acid concentrations confirmed the idea that postprandially and during starvation most of the amino acids flow from extrahepatic tissues to the liver but also showed that during starvation tryptophan, cystine, ornithine, valine, leucinc and isoleucine flow in the opposite direction, from liver to extrahepatic tissues.

3. The blood levels of the non-essential amino acids fell markedly during starvation while those of the essential ones tended to be maintained. This contrasts with the pattern of changes known to take place in rats and man given low-protein diets. In the liver, changes in amino acid concentrations were generally related to those in the blood but not strictly parallel. The relative changes in amino acid concentrations in blood and liver indicate that as starvation progresses the concentrative ability of the liver is enhanced for most of the amino acids which are taken up and that the increased output of those which are released is also due to changed membrane transport.

4. The changes in plasma amino acid concentrations in the blood passing through livers of rats starved for 1 d were, except for tryptophan and perhaps cystine, consistent with the extracellular changes found during perfusion of livers form rats straved for 1 d, indicating that the perfused liver influences concentrations of extracellular amino acids substantially as it does in vivo.

5. The results suggest of mechanism wherby the liver may control the maintenance of the essential amino acids during starvation.

1. In the wild, red grouse live largely on heather, a high-fibre (25%), low-protein (7%) food. Digestibility trials were carried out under semi-natural conditions, with magnesium as a digestibility marker. Two trials were done, one in autumn and one in spring.

2. Digestibility of the dry matter varied from 21 to 30% and metabolizable energy from 1.1 to 1.6 kcal/g. These variations were inversely related to intake and could partly be accounted for by facultative variations in holocellulose and lignin digestion.

3. Digestion of soluble carbohydrates, protein (measured as α-amino-nitrogen) and holocellulose varied between trials according to the initial concentration in the food. The digestibility of soluble carbohydrate was high (78–83%) in autumn (16% in food) and low (61–66%) in spring (11% in food) and that of protein was relatively low (24–31%) in autumn (6% in food) and high (42–48%) in spring (7% in food). Digestibility of crude fat was 30–33% for four birds and 20% for one bird.

4. By comparison with poultry, voluntary intake of dry matter was very high relative to body-weight and intake of energy appeared to be adequate. None the less, all birds lost weight during the trials, presumably for reasons other than energy shortage.

5. Urate excretion increased in parallel with body-weight losses, but formed only 2% of the total N output at low weight losses, in which event the main nitrogenous compounds in the droppings were α-amino N (presumably largely from undigested protein), ammonium salts and ornithuric acid.

6. The ornithuric acid was presumably a detoxication product of prolignins and possibly tannins and other polyphenols. Its excretion by grouse corresponds to the excretion of hippuric acid by ruminants.

1. Diets containing varying levels of crude protein (CP) in the range 9.5–18.5% with and without supplements of diammonium citrate (DAC) as a source of non-protein nitrogen (NPN) were given to 160 growing chicks from 2 to 4 weeks of age, and their livers were assayed for glumate dehydrogenase (GDH) activity.

2. Growth rate and total liver protein were increased by raising the protein level from 9.5 to 18.5% CP. Chicks receiving 9.5 or 12.5% CP were heavier when they had also received 1.94% DAC. At 18.5% CP the addition of 3.88% DAC depressed growth.

3. GDH activity per unit liver weight and total GDH activity increased with dietary protein level but there were no consistent responses to DAC supplements. It was concluded that liver GDH activity did not provide a useful index of the utilization of NPN.

1. The intestinal absorption of [11,12 3H2] retinyl acetate was studied in five apparently normal children, eight children with respiratory infection and three with gastroenteritis.

2. The absorption of vitamin A was significantly lower in children with respiratory infection or gastroenteritis than in normal children.

3. In the light of these observations, it is suggested that repeated attacks of infections may significantly contribute to the prevalence of vitamin A deficiency in children of poor communities.