Maternal diet influences breast milk nutritional profile; however, it is unclear which nutrients and contaminants are particularly responsive to short- and long-term changes in maternal intake, and the impact of specific exclusion diets, such as vegan or vegetarian. This study systematically reviewed the literature on the effects of maternal nutrient intake, including exclusion diets, on both the nutrient and contaminant content of breast milk. The electronic databases, PubMed, CENTRAL, Web of Science and CINALH were systematically searched until 4 June 2023, with additionally searches of reference lists (PROSPERO, CRD42020221577). The quality of the studies was examined using Cochrane Risk of Bias tool and Newcastle–Ottawa scale. Eighty-eight studies (n 6577) met the search criteria. Due to high heterogeneity, meta-analysis was not possible. There was strong evidence of response to maternal intakes for DHA and EPA, vitamins A, E and K, iodine and Se in breast milk composition, some evidence of response for α-linolenic acid, B vitamins, vitamin C and D, ovalbumin, tyrosine and contaminants, and insufficient evidence to identify the effects arachidonic acid, Cu, Fe, Zn and choline. The paucity of evidence and high heterogeneity among studies reflects the need for more high-quality trials. However, this review identified the importance of maternal intake in the nutritional content of breast milk for a wide range of nutrients and supports the recommendation for supplementation of DHA and vitamin B12 for those on restrictive diets.

The peptide hormone hepcidin functions as a negative regulator of intestinal Fe absorption and Fe recycling. Since its discovery as a systemic negative regulator of Fe metabolism, hepcidin has attracted enormous interest as a potential drug for the treatment and/or prevention of several forms of Fe overload. We therefore tested whether multiple doses of intraperitoneally administered synthetic renatured hepcidin can prevent hepatic Fe loading in mice concurrently fed an Fe-rich diet, and whether the same treatment affects hepatic Fe stores in mice fed a normal diet. Cohorts of male mice were fed either a normal defined diet (180 parts per million Fe) or an Fe-rich diet (the same diet supplemented with 2 % carbonyl iron for 2 weeks). Concurrently, half of the animals in each diet group received 100 μg of renatured hepcidin intraperitoneally every 12 h, for the same 2-week period. The second half of the animals received PBS only. The renatured synthetic hepcidin demonstrated biological activity by significantly decreasing transferrin saturation, which lasted for up to 24 h after a single hepcidin dose. However, the 14 d intraperitoneal hepcidin therapy did not prevent hepatic Fe overload in mice fed the Fe-rich diet, nor did it affect hepatic Fe stores in mice fed the normal diet. Both hepcidin agonists and antagonists are expected to have broad therapeutic potential. The absence of an effect of biologically active hepcidin on hepatic Fe loading shows the need for thorough future studies on the hepcidin regulation of Fe absorption and tissue distribution.

We have previously reported that dietary fructose rapidly induces jejunal sucrase–isomaltase (SI) gene expression in rats. In this study, we confirmed in mice that SI mRNA was induced 6 h after force-feeding fructose, but not glucose. Using the chromatin immunoprecipitation assay, we revealed that histones H3 and H4 on the promoter/enhancer regions of the SI gene in mice given fructose were highly acetylated, compared with those given glucose or water. These results suggest that acute induction of SI gene expression by dietary fructose is associated with acetylation of histones H3 and H4 on the SI gene.

1. Twelve young men were given for periods of 20 d, each of three mixed diets, namely a low-protein (LP) diet (9% total energy as protein, 67% of animal origin), a high-animal-protein (HA) diet (16% total energy as protein, 67% of animal origin) and a high-vegetable-protein (HV) diet (16% total energy as protein, 67% of vegetable origin). Retention of calcium, magnesium, iron, zinc and copper as well as various bowel function indices were investigated during each dietary period.

2. Neither the HA diet nor the HV diet changed the retention of the minerals considerably. Only Fe balance decreased significantly on the HV diet.

3. Substituting the HV diet for the HA diet resulted in significant increases in faecal wet weight (17 g/d), defaecation frequency (0.12 stools/d), faecal volatile fatty acids (2.6 mmol/d) and a decrease in faecal bile acids (128 μmol/d).

4. It is concluded that a HV diet, rather than a HA diet is to be recommended with respect to bowel function, whereas the HV diet does not necessarily have a significant influence on mineral retention.

Prisoners experience a higher burden of poor health, aggressive behaviours and worsening mental health than the general population. This systematic review aimed to identify research that used nutrition-based interventions in prisons, focusing on outcomes of mental health and behaviours. The systematic review was registered with Prospective Register of Systematic Reviews on 26 January 2022: CRD42022293370. Inclusion criteria comprised of current prisoners with no limit on time, location, age, sex or ethnicity. Only quantitative research in the English language was included. PubMed/Medline, Web of Science, EMBASE, PsycINFO and CINAHL were searched, retrieving 933 results, with 11 included for qualitative synthesis. Studies were checked for quality using the revised tool to assess risk of bias in randomised trials or risk of bias in non-randomised studies of interventions tool. Of the included studies, seven used nutritional supplements, three included diet changes, and one used education. Of the seven supplement-based studies, six included rule violations as an outcome, and only three demonstrated significant improvements. One study included mental health as an outcome; however, results did not reach significance. Of the three diet change studies, two investigated cognitive function as an outcome, with both reaching significance. Anxiety was included in one diet change study, which found a significant improvement through consuming oily fish. One study using diet education did not find a significant improvement in overall mental resilience. Overall, results are mixed, with the included studies presenting several limitations and heterogeneity. Future research should aim to consider increased homogeneity in research design, allowing for a higher quality of evidence to assess the role nutrition can play in improving the health of prisoners.

1. Male, adult guinea-pigs received a scorbutogenic diet and a daily supplement of 1.0 mg ascorbic acid/100 g body-weight.

2. Restriction of food intake for a period of 17 d resulted in a 25 % loss in body-weight and a significant reduction in the retention of ascorbic acid by the spleen, liver and adrenal glands.

1. Nutritional factors affecting the urinary excretion of acid-soluble peptides (ASP) were studied in rats. The ratio, total urinary nitrogen: ASP-form leucine + valine was lowest in the rats fed on a protein-free diet and increased as retained N: absorbed N decreased. The ratio was not affected by dietary protein level when the level was below the National Research Council (1978) recommended requirement, but increased greatly when it exceeded the recommended requirement.

2. The excretion of ASP-form leucine + valine per kg body-weight was significantly lower in the protein- deficient rats than in those fed on protein-adequate diets. This variable decreased during the stage of rapid growth, but did not change as markedly after the onset of adolescence. It increased again when the rats became older. The patterns of change in the rate of excretion of ASP-form amino acids during growth and that of Nr-methylhistidine were different.

3. When labelled amino acids were injected into rats, the largest amount of the ASP-form label was excreted on the 1st day of injection. From the 2nd day the excretion of ASP-form label decreased exponentially.

4. The findings suggest that the rate of urinary excretion of ASP-form amino acids can be employed as an index of protein metabolism, particularly as a simple index of the assessment of the status of protein nutrition.

1. To study the efficiency of rehabilitation after different periods of protein–energy malnutrition, we used as a model preweaning malnourished rats. After weaning, male Wistar rats were fed on a protein-deficient diet (50 g casein/kg) ad lib. for the whole study (DR group) or rehabilitated with normal diet (180 g casein/kg; RR group) from weaning, week 0, or weeks 1, 3, 5, 8 and 16 thereafter.

2. Twelve animals from the DR group were killed at the beginning of each rehabilitation period. The twelve rehabilitated rats were killed after 2 weeks. Body-weight and epididymal adipose tissue weight, blood glucose, plasma immunoreactive insulin (IRI) and immunoreactive glucagon (IRG), and pancreatic contents of IRI and IRG were determined.

3. Food intake of RR rats rose significantly except during the last period where body-weight increased less than that during the previous periods. Fat-pad weights increased in the same manner in DR and RR groups.

4. Blood glucose fell and plasma IRG rose significantly without any change in plasma IRI after each rehabilitation period, except during the last period where blood glucose concentrations became stable. Pancreatic IRG and IRI showed the same type of response to those of the plasma.

5. All short-term rehabilitation periods were similarly efficient at producing catch-up growth. High insulin sensitivity of target cells was responsible for good recovery except after long-term malnutrition.

Two formulas were derived to estimate the energy content of the human body which use only body mass, total body water by 3H2O dilution space and body minerals assessed by anthropometry. The formulas were tested in a body composition database of 561 patients and 151 normal volunteers using established metabolizable energy values for protein, fat and glycogen. Total body protein was determined by in vivo neutron activation analysis (IVNAA), body water by dilution of tritium and body minerals from skeletal frame size. Body glycogen was assumed to be 14.6 % of the mineral component. Body fat was obtained by difference, body mass less the sum of water, protein, minerals and glycogen. The standard deviation in the estimate of body energy content was 30 MJ or 4.1 % of the energy content of reference man. Two formulas for body energy content were derived by regression with body mass, total body water and body minerals or height. Two formulas for energy density and formulas for percentage body fat were similarly derived.

The effect of early transition of the digestive system to exogenous nutrition was examined in three experiments with growing birds. A nutrient mixture (0·5 ml) of glucose, starch and oil (1:1:0·5, by vol) was orally administered immediately after hatch to turkey poults (Meleagris gallopavo) having immediate or delayed access to feed (Expt 1). Increasing amounts (0, 0·25 and 0·5 ml) of this mixture were administered immediately after hatch to turkey poults (Expt 2), or to broiler chicks (Gallus domesticus; Expt 3). The relative weights of the gastrointestinal tract (GIT) and its ingesta content, and the amylolytic capability of the pancreas were examined during the immediate post-hatch period (to 30 h). Oral administration of nutrients immediately after hatching only slightly influenced the growth of the pancreas and its amylolytic activity, but significantly increased GIT weight in both species, in a dose-dependent manne. It is suggested that early post-hatching of the digestive system by the forced administration of nutrient mixture induces anatomical and metabolic changes in the digestive system slightly earlier than in birds with late access to feed. This increases GIT content and plasma glucose levels, resulting in enhanced feed consumption and growth promotion.

Incorporation of 2·5 g/kg of the anorexigen, simmondsin, in the diet resulted in food intake reduction in both lean and obese Zucker rats; however, the obese rats were much more sensitive to the food intake-reducing activity of simmondsin. In both obese and lean simmondsin-treated Zucker rats, growth was slower than in control rats, but was the same as that in pair-fed animals. The 24 h heat production pattern showed a smaller diurnal variation and a lower mean in obese rats than in lean rats. Food intake reduction, as a result of either simmondsin treatment or pair feeding, caused a decrease in mean heat production. Simmondsin treatment, but not pair feeding, caused a decrease in the diurnal variation of heat production. Plasma total cholesterol levels were increased in both simmondsin-treated and pair-fed obese and lean Zucker rats compared with control animals; this increase was mainly due to an increase in HDL-cholesterol levels. Blood leptin levels in both obese and lean rats decreased with decreased food intake and decreased fat deposition, but in obese rats, simmondsin treatment resulted in an additional decrease in leptin levels. It is concluded that the food intake-reducing effect of simmondsin is more pronounced in obese Zucker rats than in their lean littermates, and except for the simmondsin-specific effects on leptin and total cholesterol values in obese littermates, the effects of simmondsin are related to food intake restriction in obese and lean Zucker rats.

1. The metabolism of dehydroretinyl ester has been studied in vitamin-A-deficient white leghorn chicks. Dehydroretinyl ester was metabolized to 3-hydroxyretinol diester, 3-hydroxyanhydroretinol and rehydrovitamin A2 which were isolated from the intestines and livers of chicks.

2. The metabolism of 3-hydroxyretinol diester and 3-hydroxyanhydroretinol, which were immediate metabolites of dehydroretinol, was studied in chicks.

3. Retinol was not detected in these experiments.

The food industry has five important roles in facilitating needed dietary and behavioural changes. Two of these roles are direct ones. Industry can increase the availability of a wide variety of basic commodities and new foods that help consumers meet dietary recommendations. It is also responsible for developing and formulating appealing, healthy and effective food products that decrease risks of chronic degenerative disease. Industry also plays an indirect role in facilitating dietary change by motivating consumers to select and prepare foods that will result in healthy dietary patterns. It can also participate in coalitions to facilitate other behaviours that decrease risks. Finally, it can collaborate actively in applied and fundamental research to further our understanding of the associations between food and health.