British Journal of Nutrition最新文献

This study verified the accuracy of the international BMI references and the allometric BMI reference to diagnose obesity in children and adolescents from the USA. Data from 17 313 subjects were obtained from the National Health and Nutrition Examination Survey between the years 1999-2006 and 2011-2018. Fat Mass Index, Allometric Fat Mass Index and fat mass/fat-free mass were calculated. Receiver operating characteristic curve, AUC, sensitivity, specificity, positive likelihood ratio and negative likelihood ratio were estimated to evaluate the accuracy of the growth references for diagnosing obesity. The International Obesity Task Force, MULT BMI 17 years, MULT BMI 18 years and allometric BMI 19 years achieved the best sensitivity-specificity trade-off for boys, with sensitivities ranging from 0·92 to 0·96 and specificities of 0·94, with positive likelihood ratio of 15·51, 16·17, 13·46 and 18·01, respectively. The negative likelihood ratios were notably low, ranging from 0·04 to 0·08. In girls, the International Obesity Task Force, MULT BMI 17 years and MULT allometric BMI 17 years also demonstrated high sensitivity (0·95-0·97) and specificity (0·92), with positive likelihood ratio values of 11·54, 11·82 and 11·77, respectively and low negative likelihood ratio values (0·03-0·05). In summary, these international growth references presented satisfactory performance to diagnose obesity. However, the MULT growth reference performed better, and the MULT allometric BMI was the only indicator capable of detecting that girls have a higher proportion of fat mass than boys for the same index values. These findings suggest that the MULT growth reference may be a better tool to assess the nutritional status of children and adolescents internationally.

Vitamin D deficiency has previously been linked to higher rates of exacerbation and reduced lung function in asthmatics. Previous randomised controlled trials investigating the effect of vitamin D supplementation have mainly focused on children with asthma. Trials involving adults have typically used bolus dosing regimens, and the main outcomes have been patient-focused without investigating underlying inflammation. The present study aimed to conduct a 12-week placebo-controlled randomised controlled trials administering a daily 125 µg vitamin D₃ supplement to adults with mild to moderate asthma. A total of 32 participants were randomised to receive either the 125 μg vitamin D₃ supplement or an identical matching placebo. The primary outcome of the study was lung function measured by the ratio of FEV₁:FVC (effect size 2·5) with secondary outcomes including asthma symptoms and inflammatory biomarkers. There was a small but statistically significant higher increase in the mean (±sd) ratio of FEV₁:FVC from baseline to post-intervention in the vitamin D group (+0·05 ± 0·06) compared with the placebo group (+0·006 ± 0·04, P = 0·04). There was no effect of the intervention on asthma control test scores, or the inflammatory biomarkers measured. There was a moderate, significant association between baseline plasma 25(OH)D concentration and baseline plasma IL-10 (r = 0·527, P = 0·005) and TNF-α (r = −0·498. P = 0·008) concentrations. A daily vitamin D₃ supplement led to slightly improved lung function in adult asthmatics and may be a useful adjunct to existing asthma control strategies, particularly for individuals with suboptimal vitamin D status.

High dietary salt intake is a known risk factor for hypertension. However, Australians continue to consume excessive amounts of salt. The purpose of this study was to identify barriers, enablers and strategies to reduce salt in a sample of Australian adults with hypertension. This was a qualitative study. Participants were asked a set of open-ended questions during focus groups conducted between October 2020 and April 2021. Sessions were recorded and transcribed. Using an inductive approach, the transcript data from the focus groups were thematically analysed. This involved checking accuracy, becoming familiar with the data, coding responses based on questions, identifying themes through common patterns and validating themes by grouping similar questions that represented the data and study aim effectively. Thirty-one adults (55 % females) with high blood pressure participated in the focus group discussions. Participants demonstrated good knowledge of high blood pressure risk factors but lacked an understanding of recommended salt intake levels and sources of hidden salt. Challenges in reducing salt intake included the limited availability of low-salt commercial foods. Participants suggested improved food labelling and the use of technology-based interventions to promote healthier choices. Findings highlight the need for behavioural interventions, policy reforms and collaborations between the government, food industries and health organisations to address high salt intake in the population.

Plant-derived proteins are often deficient in essential amino acids and have lower rates of digestibility than animal-derived proteins. Blending different plant-derived proteins could compensate for these deficiencies and may augment postprandial aminoacidemia over single-source plant proteins. This study assessed plasma amino acids and appetite hormones, appetite sensations and ad libitum energy intake following ingestion of a pea-rice protein blend (BLEND), compared with pea-only (PEA) and whey (WHEY) protein. In a randomised, double-blind, crossover design, ten healthy adults (M n 4, F n 6; mean (sd) age 22 (sd 3) years; BMI 24 (sd 3) kg·m²) ingested 0·3 g·kg·body mass^-1 of BLEND, PEA or WHEY. Arterialised venous blood samples and appetite ratings were obtained in the fasted state and over 240 min postprandially. Energy intake was measured via an ad libitum buffet-style test meal. Mean plasma essential amino acid incremental AUC was higher in WHEY, compared with PEA (P < 0·01; mean diff (95 % CI): 44 218 (15 806, 72 631) μmol·240 min·l^-1) and BLEND (P < 0·01; 14 358 (16 031, 101 121) μmol·240 min·l^-1), with no differences between PEA and BLEND (P = 0·67). Plasma ghrelin and glucagon-like peptide-1, appetite ratings and ad libitum energy intake responses did not differ between treatments (P > 0·05 for all). Ingestion of a pea-rice protein blend did not augment postprandial aminoacidemia above pea protein, perhaps attributable to marginal differences in essential amino acid composition. No between-treatment differences in appetite or energy intake responses were apparent, suggesting that the influence of protein ingestion on perceived appetite ratings and orexigenic hormonal responses may not be solely determined by postprandial plasma aminoacidemia.

Pregnancy weight gain standards are charts describing percentiles of weight gain among participants with no risk factors that could adversely affect weight gain. This detailed information is burdensome to collect. We investigated the extent to which exclusion of various pre-pregnancy, pregnancy and postpartum factors impacted the values of pregnancy weight gain percentiles. We examined pregnancy weight gain (kg) among 3178 participants of the US nuMoM2b-Heart Health Study (HHS). We identified five groups of potential exclusion criteria for pregnancy weight gain standards: socio-economic characteristics (group 1), maternal morbidities (group 2), lifestyle/behaviour factors (group 3), adverse neonatal outcomes (group 4) and longer-term adverse outcomes (group 5). We established the impact of different exclusion criteria by comparing the median, 25th and 75th percentiles of weight gain in the full cohort with the values after applying each of the five exclusion criteria groups. Differences > 0·75 kg were considered meaningful. Excluding participants with group 1, 2, 3 or 4 exclusion criteria had no impact on the 25th, median or 75th percentiles of pregnancy weight gain. Percentiles were only meaningfully different after excluding participants in group 5 (longer-term adverse outcomes), which shifted the upper end of the weight gain distribution to lower values (e.g. 75th percentile decreased from 19·6 kg to 17·8 kg). This shift was due to exclusion of participants with excess postpartum weight retention > 5 kg or > 10 kg. Except for excess postpartum weight retention, most potential exclusion criteria for pregnancy weight gain standards did not meaningfully impact chart percentiles.

Deficiency of vitamin B₁₂ (B₁₂ or cobalamin), an essential water-soluble vitamin, leads to neurological damage, which can be irreversible and anaemia, and is sometimes associated with chronic disorders such as osteoporosis and cardiovascular diseases. Clinical tests to detect B₁₂ deficiency lack specificity and sensitivity. Delays in detecting B₁₂ deficiency pose a major threat because the progressive decline in organ functions may go unnoticed until the damage is advanced or irreversible. Here, using targeted unbiased metabolomic profiling in the sera of subjects with low B₁₂ levels v control individuals, we set out to identify biomarker(s) of B₁₂ insufficiency. Metabolomic profiling identified seventy-seven metabolites, and partial least squares discriminant analysis and hierarchical clustering analysis showed a differential abundance of taurine, xanthine, hypoxanthine, chenodeoxycholic acid, neopterin and glycocholic acid in subjects with low B₁₂ levels. Random forest multivariate analysis identified a taurine/chenodeoxycholic acid ratio, with an AUC score of 1, to be the best biomarker to predict low B₁₂ levels. Mechanistic studies using a mouse model of B₁₂ deficiency showed that B₁₂ deficiency reshaped the transcriptomic and metabolomic landscape of the cell, identifying a downregulation of methionine, taurine, urea cycle and nucleotide metabolism and an upregulation of Krebs cycle. Thus, we propose taurine/chenodeoxycholic acid ratio in serum as a potential biomarker of low B₁₂ levels in humans and elucidate using a mouse model of cellular metabolic pathways regulated by B₁₂ deficiency.

During the first thousand days of life, fetus and infant's nutrition depends on mother's diet. Polyunsaturated fatty acids (PUFA) are important substrates in infant neurogenesis. We related erythrocyte membrane (EM) and breast milk fatty acids (FA) profile in lactating mothers with the EM FA profile in exclusively breastfed infants and evaluated maternal fat consumption. We conducted an observational, cross-sectional analytical study. During the 2016-2019 period, milk and blood samples from adult mothers 90 days post-partum and infant's blood were analysed, and FA were determined by GC. A frequency of consumption survey of fatty acids precursor foods and sources was conducted. The sample included forty-five mother-infant EM and forty-five milk samples donated by the same mothers. A low percentage of DHA (0·14 (0·12-0·2)) was found in milk, consistent with mother's low consumption of DHA-rich foods. A significant positive correlation between infant's EM DHA percentage and milk DHA percentage (r = 0·39; P value 0·008), as well as between infant's EM ω-3 fatty acids sum and milk DHA percentage (r = 0·39; P value 0·008), was found. When milk had a DHA percentage greater than or equal to 0·20 %, infants had a significant increase in DHA in their EM. Mother's consumption of DHA precursors and sources was NS. The relation between the DHA percentage distribution found in maternal milk, and the DHA percentage distribution found in infant's and mother's EM was proven in this population. Dietary fatty acid intake is associated with the maternal milk lipid distribution and with mothers' and infant's EM fatty acids percentage.

Adequate fruit and vegetable consumption is essential for healthy ageing and prevention and management of chronic disease. This study aimed to examine characteristics associated with fruit and vegetable consumption in Chinese men and women aged 50 years and over. Data from the first wave of the Chinese cohort (2008-2010) of the WHO's Study on global AGEing and adult health (SAGE) survey was used. Fruit and vegetable consumption was assessed by self-reported typical consumption in serves/day. Characteristics examined were age, education, financial security, home ownership, marital status, social cohesion and rural location. Associations with fruit and vegetable consumption were assessed using multiple linear regression adjusted for confounders and stratified by sex. Overall, women consumed more serves of fruit per day than men (mean (standard deviation): 2·6 (2·2) and 2·2 (2·1) serves/day, respectively) whereas men consumed more serves of vegetables than women (7·2 (4·0) and 6·7 (3·7)). Lower fruit consumption was associated with lower education, lower social participation, income insecurity, renting, being un-partnered and rural residency in men and women, as well as older age in women. Lower vegetable consumption was associated with older age, lower education and urban residency in men and women and lower social participation in men and being unpartnered in women. This study has identified characteristics associated with fruit and vegetable intake in a sample of mid aged and older Chinese men and women. Further research on the interrelationships between these characteristics and fruit and vegetable intake as well as longitudinal relationships is warranted.

Previous studies have indicated an association between vitamin D and thyroid- and parathyroid-related diseases. However, it remains unclear whether it is a cause of the disease, a side effect of treatment or a consequence of the disease. The Mendelian randomisation (MR) study strengthens the causal inference by controlling for non-heritable environmental confounders and reverse causation. In this study, a two-sample bidirectional MR analysis was conducted to investigate the causal relationship between serum vitamin D levels and thyroid- and parathyroid-related diseases. Inverse variance weighted, weighted median and MR-Egger methods were performed, the Cochran Q test was used to evaluate the heterogeneity and the MR-PRESSO and MR-Egger intercepts were utilised to assess the possibility of pleiotropy. The Bonferroni-corrected significance threshold was 0·0038. At the Bonferroni-corrected significance level, we found that vitamin D levels suggestively decreased the risk of benign parathyroid adenoma (OR = 0·244; 95 % CI 0·074, 0·802; P = 0·0202) in the MR analyses. In the reverse MR study, a genetically predicted risk of thyroid cancer suggestively increased the risk of elevated vitamin D (OR = 1·007; 95 % CI 1·010, 1·013; P = 0·0284), chronic thyroiditis significantly increased the risk of elevated vitamin D (OR = 1·007; 95 % CI 1·002, 1·011; P = 0·0030) and thyroid nodules was significantly decreased the vitamin D levels (OR = 0·991; 95 % CI 0·985, 0·997; P = 0·0034). The findings might be less susceptible to horizontal pleiotropy and heterogeneity (P > 0·05). This study from a gene perspective indicated that chronic thyroiditis and thyroid nodules may impact vitamin D levels, but the underlying mechanisms require further investigation.