COVID-19, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), was recognised by the WHO as a pandemic in 2020. Host preparation to combat the virus is an important strategy to avoid COVID-19 severity. Thus, the relationship between eating habits, nutritional status and their effects on the immune response and further implications in viral respiratory infections is an important topic discussed in this review. Malnutrition causes the most diverse alterations in the immune system, suppressing of the immune response and increasing the susceptibility to infections such as SARS-CoV-2. On the other hand, obesity induces low-grade chronic inflammation caused by excess adiposity, which increases angiotensin-converting enzyme 2. It decreases the immune response favouring SARS-CoV-2 virulence and promoting respiratory distress syndrome. The present review highlights the importance of food choices considering their inflammatory effects, consequently increasing the viral susceptibility observed in malnutrition and obesity. Healthy eating habits, micronutrients, bioactive compounds and probiotics are strategies for COVID-19 prevention. Therefore, a diversified and balanced diet can contribute to the improvement of the immune response to viral infections such as COVID-19.

An 8-week feeding trial was conducted to evaluate the effects of dietary n-3 LC-PUFA levels on growth performance, tissue fatty acid profiles and relative expression of genes involved in the lipid metabolism of mud crab (Scylla paramamosain). Ten isonitrogenous diets were formulated to contain five n-3 LC-PUFA levels at 7 and 12 % dietary lipid levels. The highest weight gain and specific growth rate were observed in crabs fed the diets with 19·8 and 13·2 mg/g n-3 LC-PUFA at 7 and 12 % lipid, respectively. Moisture and lipid contents in hepatopancreas and muscle were significantly influenced by dietary n-3 LC-PUFA at the two lipid levels. The DHA, EPA, n-3 LC-PUFA contents and n-3:n-6 PUFA ratio in hepatopancreas and muscle significantly increased as dietary n-3 LC-PUFA levels increased at both lipid levels. The expression levels of -6 fatty acyl desaturase and acyl-CoA oxidase in hepatopancreas increased significantly, and expression levels of fatty acid synthase, carnitine palmitoyltransferase I and hormone-sensitive TAG lipase were down-regulated, with increased dietary n-3 LC-PUFA regardless of lipid level. Based on weight gain, n-3 LC-PUFA requirements of S. paramamosain were estimated to be 20·1 and 12·7 mg/g of diet at 7 and 12 % dietary lipid, respectively. Overall, dietary lipid level influenced lipid metabolism, and purified, high-lipid diets rich in palmitic acid reduced the n-3 LC-PUFA requirement of juvenile mud crab.

Food pantries provide free food to individuals at nutritional risk given lack of available foods. Frequent use of food pantries is associated with higher dietary quality; however, neither the nutrient contributions of food pantries to participant diets nor their relationship with household food security are known. This cross-sectional analysis used secondary data from rural food pantry participants, including sociodemographic characteristics, household food security and 24-h recalls. Mean intakes of selected food groups and nutrients from food pantries, supermarkets, other stores and restaurants, and other were compared by one-way ANCOVA. Interaction effects of household food security with food sources were evaluated by two-way ANCOVA. About 40 % of participants’ dietary intake came from food pantries. Mean intakes of fibre (P < 0·0001), Na (P < 0·0001), fruit (P < 0·0001), grains (P < 0·0001) and oils (P < 0·0001) were higher from food pantries compared with all other sources, as were Ca (P = 0·004), vitamin D (P < 0·0001) and K (P < 0·0001) from food pantries compared with two other sources. Percentage total energy intake (%TEI) from added sugars (P < 0·0001) and saturated fat (P < 0·0001) was higher from supermarkets than most other sources. Significant interaction effects were observed between food sources and household food security for vegetables (P = 0·01), Na (P = 0·01) and %TEI from saturated fat (P = 0·004), with food-insecure participants having significantly higher intakes from food pantries and/or supermarkets compared with all other sources. Future interventions may incorporate these findings by providing education on purchasing and preparing healthy meals on limited budgets, to complement foods received from pantries, and by reducing Na in pantry environments.

Nutrient profiling systems (NPS) are used to classify foods according to their nutritional composition. However, investigating their prospective associations with health is key to their validation. The study investigated the associations of the original Food Standards Agency (FSA)-NPS and three variants (Food Standards Australia New Zealand Nutrient Profiling Scoring Criterion (NPSC), Health Star Rating NPS and the French High Council of Public Health NPS (HCSP-NPS)), with weight status. Individual dietary indices based on each NPS at the food level were computed to characterise the dietary quality of 71 403 French individuals from the NutriNet-Santé cohort. Associations of these indices with weight gain were assessed using mixed models and with overweight and obesity risks using Cox models. Participants with a higher dietary index (reflecting lower diet nutritional quality) were more likely to have a significant increase in BMI over time (β-coefficients positive) and an increased risk of overweight (hazard ratio (HR) T3 v. T1 = 1·27 (95 % CI 1·17, 1·37)) for the HCSP-Dietary Index, followed by the original FSA-Dietary Index (HR T3 v. T1 = 1·18 (95 % CI 1·09, 1·28)), the NPSC-Dietary Index (HR T3 v. T1 = 1·14 (95 % CI 1·06, 1·24)) and the Health Star Rating-Dietary Index (HR T3 v. T1 = 1·12 (95 % CI 1·04, 1·21)). Whilst differences were small, the HCSP-Dietary Index appeared to show significantly greater association with overweight risk. Overall, these results show the validity of NPS derived from the FSA-NPS, supporting their use in public policies for chronic disease prevention.

Replacing intake of SFA with PUFA reduces serum cholesterol levels and CVD risk. The effect on glycaemic regulation is, however, less clear. The main objective of the present study was to investigate the short-term effect of replacing dietary SFA with PUFA on glycaemic regulation. Seventeen healthy, normal-weight participants completed a 25-d double-blind, randomised and controlled two-period crossover study. Participants were allocated to either interventions with PUFA products or SFA products (control) in a random order for three consecutive days, separated by a 1·5-week washout period between the intervention periods. Glucose, insulin and TAG were measured before and after an oral glucose tolerance test. In addition, fasting total cholesterol, NEFA and plasma total fatty acid profile were measured before and after the 3-d interventions. Fasting and postprandial glucose, insulin, and TAG levels and fasting levels of NEFA and plasma fatty acid profile did not differ between the groups. However, replacing dietary SFA with PUFA significantly reduced total cholesterol levels by 8 % after 3 d (P = 0·002). Replacing dietary SFA with PUFA for only 3 d has beneficial cardio-metabolic effects by reducing cholesterol levels in healthy individuals.

Increased intake of vegetables and fruits has been associated with reduced risk of tuberculosis infection. Vegetables and fruits exert immunoregulatory effects; however, it is not clear whether vegetables and fruits have an adjuvant treatment effect on tuberculosis. Between 2009 and 2013, a hospital-based cohort study was conducted in Linyi, Shandong Province, China. Treatment outcome was ascertained by sputum smear and chest computerised tomography, and dietary intake was assessed by a semi-quantitative FFQ. The dietary questionnaire was conducted at the end of month 2 of treatment initiation. Participants recalled their dietary intake of the previous 2 months. A total of 2309 patients were enrolled in this study. After 6 months of treatment, 2099 patients were successfully treated and 210 were uncured. In multivariate models, higher intake of total vegetables and fruits (OR 0·70; 95 % CI 0·49, 0·99), total vegetables (OR 0·68; 95 % CI 0·48, 0·97), dark-coloured vegetables (OR 0·61; 95 % CI 0·43, 0·86) and light-coloured vegetables (OR 0·67; 95 % CI 0·48, 0·95) were associated with reduced failure rate of tuberculosis treatment. No association was found between total fruit intake and reduced failure rate of tuberculosis treatment (OR 0·98; 95 % CI 0·70, 1·37). High intake of total vegetables and fruits, especially vegetables, is associated with lower risk of failure of tuberculosis treatment in pulmonary tuberculosis patients. The results provide important information for dietary guidelines during tuberculosis treatment.

Sweetened beverages are mainly consumed cold and various processes are activated in response to external temperature variations. However, the effect of internal temperature variations through the ingestion of cold beverages is far from clear. Two experiments were conducted to investigate the effect of beverage temperature on body composition. Sprague–Dawley rats (5–6-week-old males) had free access to food and beverage for 8 weeks. Energy intake, body weight and body composition were monitored. In Expt 1, two groups of rats (n 9) consumed water at room temperature (NW about 22°C) or cold (CW about 4°C). In Expt 2, rats were offered room-temperature (N) or cold (C) sweetened water (10 % sucrose CSu (n 7) and NSu (n 8); or 0·05 % acesulfame K CAk (n 6) and NAk (n 8)) for 12 h, followed by plain water. Our results show that in Expt 1, CW had higher lean body mass (P < 0·001) and lower body fat gain (P = 0·004) as compared with NW. In Expt 2, body weight (P = 0·013) and fat (P ≤ 0·001) gains were higher in the non-energetic sweetened groups, while lean body mass was not affected by the type of sweeteners or temperature. In conclusion, cold water ingestion improved lean body mass gain and decreased fat gain because of increased energy expenditure, while non-energetic sweetener (acesulfame K) increased body fat gain due to improved energy efficiency. Internal cold exposure failed to increase energy intake in contrast to that of external cold exposure.

The present study aimed to investigate the association of early-life exposure to famine with abdominal fat accumulation and function and further evaluate the influence of first-degree family history of diabetes and physical activity on this association. The present work analysed parts of the REACTION study. A total of 3033 women were enrolled. Central obesity was defined as waist circumferences (W) ≥ 85 cm. Chinese visceral adiposity index (CVAI) was used to evaluate visceral adipose distribution and function. Partial correlation analysis showed BMI, W, glycated Hb and CVAI were associated with early-life exposure to famine (both P < 0·05). Logistic regression showed that the risks of overall overweight/obesity and central obesity in fetal, early-childhood, mid-childhood and late-childhood exposed subgroups were increased significantly (all P < 0·05). Compared with the non-exposed group, the BMI, W and CVAI of fetal, early- to late-childhood exposed subgroups were significantly increased both in those with or without first-degree family history of diabetes and in those classified as physically active or inactive, respectively (all P < 0·05). The associations of BMI, W and CVAI with early-life exposure to famine were independent of their associations with first-degree family history of diabetes (all P < 0·01) or physical activity status (all P < 0·001). Early-life exposure to famine contributed to abdominal fat accumulation and dysfunction, which was independent of the influence of genetic background and exercise habits. Physical activity could serve as a supplementary intervention for women with high risk of central obesity.

This study examined the effect of ambient temperature on energy intake, perceived appetite and gut hormone responses during rest in men. Thirteen men (age 21·5 (sd 1·4) years; BMI 24·7 (sd 2·2) kg/m2) completed three, 5·5 h conditions in different ambient temperatures: (i) cold (10°C), (ii) thermoneutral (20°C) and (iii) hot (30°C). A standardised breakfast was consumed after fasting measures, and an ad libitum lunch provided at 4–4·5 h. Blood samples (analysed for plasma acylated ghrelin, total peptide tyrosine-tyrosine (PYY) and total glucagon-like peptide 1 (GLP-1) concentrations), perceived appetite and thermoregulatory responses were collected throughout. Linear mixed models were used for statistical analyses. Ad libitum energy intake was 1243 (sd 1342) kJ higher in 10°C and 1189 (sd 1219) kJ higher in 20 v. 30°C (P = 0·002). Plasma acylated ghrelin, total PYY and GLP-1 concentrations did not differ significantly between the conditions (P ≥ 0·303). Sensitivity analyses for the 4 h pre-lunch period showed that perceived overall appetite was lower in both 30 and 10°C when compared with 20°C (P ≤ 0·019). In conclusion, acutely resting in a hot compared with a thermoneutral and cold ambient temperature reduced lunchtime ad libitum energy intake in healthy men. Suppressed perceived appetite may have contributed to the reduced energy intake in the hot compared with thermoneutral ambient temperature, whereas gut hormones did not appear to play an important role.