The aim of the present study was to examine whether serum Zn concentrations were associated with metabolic risk factors in Chinese children and adolescents. This was a cross-sectional study including 3241 participants, aged 6 to 17 years, from Jiangsu, China. Metabolic risk factors included fasting glucose (FG), total cholesterol (TC), TAG, HDL-cholesterol, LDL-cholesterol, systolic blood pressure and diastolic blood pressure. Data were analysed using multi-variable linear regression and generalised additive models, which were adjusted for age, sex, high-sensitive C-reactive protein, estimated glomerular filtration rate, BMI and region of residence, to assess the associations of serum Zn concentrations with metabolic risk factors. We observed a negative association between serum Zn concentrations and FG (coefficient = −0·532; 95 % CI −0·569, −0·495; P < 0·001). Moreover, TC (coefficient = 0·175; 95 % CI 0·127, 0·222; P < 0·001), HDL-cholesterol (coefficient = 0·137; 95 % CI 0·082, 0·193; P < 0·001) and LDL-cholesterol (coefficient = 0·195; 95 % CI 0·128, 0·263; P < 0·001) were found to be positively associated with Zn levels. A generalised additive model showed that the negative association between serum Zn and FG was weak at lower serum Zn concentrations and was stronger with the increase in serum Zn concentrations. Additionally, a U-shaped association between serum Zn and TAG was observed. Serum Zn concentrations were associated with FG, TC, TAG, HDL-cholesterol and LDL-cholesterol levels in Chinese children and adolescents. Lower levels of serum Zn were more likely related to a poor metabolic status.

The aim of this study was to evaluate the differences in the metabolic profile and body composition of monozygotic (MZ) twins concordant and discordant for the practice of physical exercise. The sample consisted of 92 MZ twins (72.5% female and 27.5% male, mean age 25.4 ± 5.69 years), registered with the Brazilian Registry of Twins, residing in Natal, Brazil. Data collection was carried out between the years 2016 and 2018. On day 1, subjects underwent a whole-body fitness evaluation, including measures of weight, height, body composition by Dual-Energy X-ray Absorptiometry and the Cardiorespiratory Exercise Test. On day 2, 10 ml blood samples were collected (overnight fasting) to determine the lipid profile and fasting glucose. The sample was separated into three groups: Active Concordant twins (Concordant A, n = 44 subjects), Inactive Concordant twins (Concordant I, n = 22 subjects) and Discordant pairs for Physical Exercise (Discordant PE, n = 26 subjects). The results demonstrated a difference between the discordant twins for exercise and also between the active versus sedentary groups, indicating a causal effect of exercise on the fat percentage, maximum oxygen consumption (VO2max) and second ventilatory threshold variables. Between groups, a difference was also observed between the groups in ventilatory threshold, very low-density lipoprotein and triglycerides. We concluded that, regardless of genetics, the practice of physical exercise was sufficient to generate alterations in body composition and VO2max in MZ twins, but not in the lipid profile or fasting glucose.

Fruit intake is associated with lower risk of cardiometabolic diseases. However, effects of dried fruits on cardiometabolic health are not well researched. We investigated the effect of daily dried fruit consumption compared with a carbohydrate-rich snack on cardiometabolic disease risk factors in adults with increased cardiometabolic risk. A two-period randomised crossover trial was conducted in adults (n 55) with elevated BMI and at least one additional risk factor for cardiometabolic disease to compare the effects of consuming 3/4 cup/d mixed dried fruits (plums, figs, dates and raisins) or an energy- and carbohydrate-matched control snack for 4 weeks. The primary outcome was LDL-cholesterol; secondary outcomes included other lipids and lipoproteins, glucose and insulin, C-reactive protein, blood pressure and vascular stiffness. Linear mixed models were used for data analysis. Lipid and lipoprotein concentrations did not differ between conditions; however, dried fruit increased LDL-cholesterol (0·10 mmol/l, 95 % CI 0·01, 0·20) compared with baseline. Compared with the control, dried fruit increased mean fasting glucose (0·08 mmol/l, 95 % CI 0·005, 0·16; P = 0·038). Vascular outcomes, fasting insulin and C-reactive protein did not differ between conditions. Mean weight changes did not differ (P = 0·55) but tended to increase after both conditions (dried fruit 0·3 kg, 95 % CI –0·09, 0·65; control 0·4 kg, 95 % CI 0·01, 0·75). Thus, short-term daily consumption of a large portion of mixed dried plums, figs, dates and raisins, without structured dietary guidance, did not improve cardiometabolic risk factors, compared with carbohydrate-rich snacks, in adults with increased baseline cardiometabolic risk.

We aimed to identify the association of hydration status with insulin resistance (IR) and body fat distribution. A total of 14 344 adults participated in the Korea National Health and Nutrition Examination Survey 2008–2010. We used urine specific gravity (USG) to indicate hydration status, and HOMA-IR (homoeostasis model assessment of IR) and trunk:leg fat ratio (TLR) as primary outcomes. In multivariate logistic regression, the OR per 0·01 increase in USG for high IR was 1·303 (95 % CI 1·185, 1·433; P < 0·001). In multivariate generalised additive model plots, increased USG showed a J-shaped association with logarithmic HOMA-IR, with the lowest Akaike’s information criterion score of USG 1·030. Moreover, increased USG was independently associated with increased trunk fat, decreased leg fat and increased TLR. In mediation analysis, the proportion of mediation effects of USG on TLR via IR was 0·193 (95 % CI 0·132, 0·285; P < 0·001), while the proportion of mediation effects of USG on IR via TLR was 0·130 (95 % CI 0·086, 0·188; P < 0·001). Increased USG, a sign of low hydration status and presumably high vasopressin, was associated with IR and poor fat distribution. Direct effect of low hydration status may be more dominant than indirect effect via IR or fat distribution. Further studies are necessary to confirm our findings.

Epidemiological studies suggest that consumption of potatoes is associated with increased risk of cardiometabolic diseases. However, few clinical trials have empirically tested this. The aim of this single-blind, randomised, crossover study was to evaluate the effect of daily potato consumption, compared with refined grains, on risk factors for cardiometabolic diseases. It was hypothesised that no difference in cardiometabolic endpoints would be detected between conditions, but diet quality would improve with potato consumption. Healthy participants on self-selected diets received one potato-based side dish or one refined grain-based side dish daily, for 4 weeks, separated by a minimum 2-week break. Dishes were isoenergetic, carbohydrate-matched and prepared without excess saturated fat or Na. Participants were instructed to consume the side dish with a meal in place of carbohydrates habitually consumed. Lipids/lipoproteins, markers of glycaemic control, blood pressure, weight and pulse wave velocity were measured at baseline and condition endpoints. Diet quality was calculated, based on 24-h recalls, using the Healthy Eating Index (HEI)-2015. Fifty adults (female n 34; age 40 (sd 13) years; BMI 24·5 (sd 3·6) kg/m2) completed the present study. No between-condition differences were detected for fasting plasma glucose (–0·05 mmol/l, 95 % CI –0·14, 0·04; P = 0·15), the primary outcome or any other outcomes. Compared with refined grains, the HEI-2015 score (3·5, 95 % CI 0·6, 6·4; P = 0·01), K (547 mg, 95 % CI 331, 764, P < 0·001) and fibre (2·4 g, 95 % CI 0·6, 4·2, P = 0·01) were higher following the potato condition. Consuming non-fried potatoes resulted in higher diet quality, K and fibre intake, without adversely affecting cardiometabolic risk.

A high-fat (H) diet increases metabolic disorders in offspring. However, there is great variability in the literature regarding the time of exposure, composition of the H diets offered to the genitors and/or offspring and parameters evaluated. Here, we investigated the effect of a H diet subjected to the genitors on different cardio-metabolic parameters on first (F1)- and second (F2)-generation offspring. Female Fischer rats, during mating, gestation and breast-feeding, were subjected to the H diet (G0HF) or control (G0CF) diets. Part of F1 offspring becomes G1 genitors for generating the F2 offspring. After weaning, F1 and F2 rats consumed only the C diet. Nutritional, biometric, biochemical and haemodynamic parameters were evaluated. G0HF genitors had a reduction in food intake but energy intake was similar to the control group. Compared with the control group, the F1H and F2H offspring presented increased plasma leptin, insulin and fasting glucose levels, dietary intake, energy intake, adiposity index, mean arterial pressure, sympathetic drive evidenced by the hexamethonium and insulin resistance. Our data showed that only during mating, gestation and breast-feeding, maternal H diet induced cardio-metabolic disorders characteristic of human metabolic syndrome that were transferred to both females and males of F1 and F2 offspring, even if they were fed control diet after weaning. This process probably occurs due to the disturbance in mechanisms related to leptin that increases energy intake in F1H and F2H offspring. The present data reinforce the importance of balanced diet during pregnancy and breast-feeding for the health of the F1 and F2 offspring.

Studies on the impact of Ramadan diurnal intermittent fasting (RDIF) on the metabolic syndrome (MetS) components among healthy Muslims observing Ramadan month have yielded contradictory results. This comprehensive meta-analysis aimed to obtain a more stable estimate of the effect size of fasting during Ramadan on the MetS components, examine variability among studies, assess the generalisability of reported results and perform subgroup analyses for associated factors. We searched the CINAHL, Cochrane, EBSCOhost, Google Scholar, ProQuest Medical, PubMed/MEDLINE, ScienceDirect, Scopus and Web of Science databases for relevant studies published from 1950 to March 2019. The MetS components analysed were: waist circumference (WC), systolic blood pressure (SBP), fasting plasma/serum glucose (FG), TAG, and HDL-cholesterol. We identified eighty-five studies (4326 participants in total) that were conducted in twenty-three countries between 1982 and 2019. RDIF-induced effect sizes for the MetS components were: small reductions in WC (no. of studies K = 24, N 1557, Hedges’ g = −0·312, 95 % CI −0·387, −0·236), SBP (K = 22, N 1172, Hedges’ g = −0·239, 95 % CI −0·372, −0·106), FG (K = 51, N 2318, Hedges’ g = −0·101, 95 % CI −0·260, 0·004) and TAG (K = 63, N 2862, Hedges’ g = −0·088, 95 % CI −0·171, −0·004) and a small increase in HDL-cholesterol (K = 57, N 2771, Hedges’ g = 0·150, 95 % CI 0·064, 0·236). We concluded that among healthy people, RDIF shows small improvement in the five MetS components: WC, SBP, TAG, FG and HDL.

The aim of this study was to derive dietary patterns associated with cardio-metabolic traits and to examine whether these predict prospective changes in these traits and incidence of the metabolic syndrome (iMetS). Subjects from the Malmö Diet and Cancer Study cardiovascular cohort without cardio-metabolic disease and related drug treatments at baseline (n 4071; aged 45–67 years, 40 % men) were included. We applied reduced rank regression on thirty-eight foods to derive patterns that explain variation in response variables measured at baseline (waist circumference, TAG, HDL- and LDL-cholesterol, systolic and diastolic blood pressure, fasting glucose and insulin). Patterns were examined in relation to change in cardio-metabolic traits and iMetS in subjects who were re-examined after 16·7 years (n 2704). Two dietary patterns (‘Western’ and ‘Drinker’) were retained and explained 3·2 % of the variation in response variables. The ‘Western’ dietary pattern was inversely associated with HDL-cholesterol and positively with all other response variables (both at baseline and follow-up), but there was no association with LDL at follow-up. After adjustment for potential confounders, the ‘Western’ dietary pattern was associated with higher risk of iMetS (hazard ratio Q4 v. Q1: 1·47; 95 % CI 1·23, 1·77; Ptrend=1·5×10−5). The ‘Drinker’ dietary pattern primarily explained variation in HDL and was not associated with iMetS. In conclusion, this study supports current food-based dietary guidelines suggesting that a ‘Western’ dietary pattern with high intakes of sugar-sweetened beverages and red and processed meats and low intakes of wine, cheese, vegetables and high-fibre foods is associated with detrimental effects on cardio-metabolic health.

A major advantage of analyses on the food group level is that the results are better interpretable compared with nutrients or complex dietary patterns. Such results are also easier to transfer into recommendations on primary prevention of non-communicable diseases. As a consequence, food-based dietary guidelines (FBDG) are now the preferred approach to guide the population regarding their dietary habits. However, such guidelines should be based on a high grade of evidence as requested in many other areas of public health practice. The most straightforward approach to generate evidence is meta-analysing published data based on a careful definition of the research question. Explicit definitions of study questions should include participants, interventions/exposure, comparisons, outcomes and study design. Such type of meta-analyses should not only focus on categorical comparisons, but also on linear and non-linear dose–response associations. Risk of bias of the individual studies of the meta-analysis should be assessed, rated and the overall credibility of the results scored (e.g. using NutriGrade). Tools such as a measurement tool to assess systematic reviews or ROBIS are available to evaluate the methodological quality/risk of bias of meta-analyses. To further evaluate the complete picture of evidence, we propose conducting network meta-analyses (NMA) of intervention trials, mostly on intermediate disease markers. To rank food groups according to their impact, disability-adjusted life years can be used for the various clinical outcomes and the overall results can be compared across the food groups. For future FBDG, we recommend to implement evidence from pairwise and NMA and to quantify the health impact of diet–disease relationships.

South Asian populations are predisposed to early onset of the metabolic syndrome. Lifestyle intervention programmes have demonstrated a reduction in the metabolic syndrome and CVD risk; however, the most effective components of the multi-faceted lifestyle interventions are unknown. We studied 2637 Sri Lankan males (n 1237) and females (n 1380), with a mean BMI of 23·9 (sd 4·2) kg/m2, aged 22·5 (sd 10·0) years, who had participated in a 5-year lifestyle-modification programme to examine the effect of dietary changes on distinct components of the metabolic syndrome. The dietary intervention comprised advice to replace polished starches with unpolished starches, high-fat meat and dairy products with low-fat products and high-sugar beverages and snacks with low-sugar varieties. For the purposes of this analysis, data from the control and intensive lifestyle groups were combined. Anthropometric and biochemical data were recorded, and a FFQ was completed annually. Multiple regression was used to determine the effect of the dietary changes on distinct components of the metabolic syndrome. The ratio unpolished:polished rice was inversely related to change in fasting glucose (β=−0·084, P=0·007) and TAG (β=−0·084, P=0·005) and positively associated with change in HDL-cholesterol (β=0·066, P=0·031) at the 5-year follow-up after controlling for relevant confounders. Red meat intake was positively associated with fasting glucose concentrations (β=0·05, P=0·017), whereas low-fat (β=−0·046, P=0·018) but not high-fat dairy products (β=0·003, P=0·853) was inversely related to glucose tolerance at the follow-up visit. Replacement of polished with unpolished rice may be a particularly effective dietary advice in this and similar populations.

Little is known about the influence of meal timing and energy consumption patterns throughout the day on glucose regulation during pregnancy. We examined the association of maternal feeding patterns with glycaemic levels among lean and overweight pregnant women. In a prospective cohort study in Singapore, maternal 24-h dietary recalls, fasting glucose (FG) and 2-h postprandial glucose (2HPPG) concentrations were measured at 26–28 weeks of gestation. Women (n 985) were classified into lean (BMI<23 kg/m2) or overweight (BMI≥23 kg/m2) groups. They were further categorised as predominantly daytime (pDT) or predominantly night-time (pNT) feeders according to consumption of greater proportion of energy content from 07.00 to 18.59 hours or from 19.00 to 06.59 hours, respectively. On stratification by weight status, lean pNT feeders were found to have higher FG than lean pDT feeders (4·36 (sd 0·38) v. 4·22 (sd 0·35) mmol/l; P=0·002); however, such differences were not observed between overweight pDT and pNT feeders (4·49 (sd 0·60) v. 4·46 (sd 0·45) mmol/l; P=0·717). Using multiple linear regression with confounder adjustment, pNT feeding was associated with higher FG in the lean group (β=0·16 mmol/l; 95 % CI 0·05, 0·26; P=0·003) but not in the overweight group (β=0·02 mmol/l; 95 % CI −0·17, 0·20; P=0·879). No significant association was found between maternal feeding pattern and 2HPPG in both the lean and the overweight groups. In conclusion, pNT feeding was associated with higher FG concentration in lean but not in overweight pregnant women, suggesting that there may be an adiposity-dependent effect of maternal feeding patterns on glucose tolerance during pregnancy.

Elevated plasma uric acid concentration is a risk factor for gout, insulin resistance and type 2 diabetes. Quercetin, a flavonoid found in high levels in onions, tea and apples, inhibits xanthine oxidoreductase in vitro, the final step in intracellular uric acid production, indicating that quercetin might be able to lower blood uric acid in humans. We determined the effects of 4 weeks of oral supplementation of quercetin on plasma uric acid, blood pressure and fasting glucose. This randomised, double-blinded, placebo-controlled, cross-over trial recruited twenty-two healthy males (19–60 years) with baseline plasma uric acid concentration in the higher, but still considered healthy, range (339 (sd 51) µmol/l). The intervention included one tablet containing 500 mg quercetin daily for 4 weeks, compared with placebo, with a 4-week washout period between treatments. The primary outcome was change in concentrations of plasma uric acid after 2 and 4 weeks; secondary outcome measures were changes in fasting plasma glucose, 24-h urinary excretion of uric acid and resting blood pressure. After quercetin treatment, plasma uric acid concentrations were significantly lowered by −26·5 µmol/l (95 % CI, −7·6, −45·5; P=0·008), without affecting fasting glucose, urinary excretion of uric acid or blood pressure. Daily supplementation of 500 mg quercetin, containing the bioavailable amount of quercetin as present in approximately 100 g red onions, for 4 weeks, significantly reduces elevated plasma uric acid concentrations in healthy males.