Associations of body shapes with insulin resistance and cardiometabolic risk in middle-aged and elderly Chinese

The Minimum Methionine Requirement for Adults Aged ≥60 Years Is the Same in Males and Females

The minimum methionine requirement in the presence of excess dietary cysteine has not been determined in older adults. This study aimed to determine the minimum methionine requirement in healthy older adults using the indicator amino acid oxidation (IAAO) method. Fifteen healthy adults ≥ 60 years of age received seven methionine intakes (0 to 20 mg/kg/d) plus excess dietary cysteine (40 mg/kg/d). Oxidation of the indicator, L-[1-13C]phenylalanine (F13CO2), was used to estimate the mean minimum methionine requirement using a change-point mixed-effect model. There was no statistical difference between male and female requirement estimates, so the data were pooled to generate a mean of 5.1 mg/kg/d (Rm2 = 0.46, Rc2 = 0.77; p < 0.01; 95% CI: 3.67, 6.53 mg/kg/d). This is the first study to estimate the minimum methionine requirement in healthy older adults, which is the same between the sexes and as our lab's previous estimate in young adults. The findings are relevant considering current recommendations for increased consumption of plant foods, which will help to establish the appropriate balance of methionine and cysteine intake required to satisfy the sulphur amino acid requirements of older adults.

Association of neck circumference-related indices with metabolic, atherogenic and liver function biomarkers in patients with non-alcoholic fatty liver disease: a cross-sectional study

OBJECTIVE

The present study aimed to establish the association of neck circumference (NC)-related indices with metabolic, atherogenic and liver function biomarkers in patients with non-alcoholic fatty liver disease (NAFLD).

DESIGN

Cross-sectional study.

SETTING

Outpatient clinics of Tabriz University of Medical Sciences.

PARTICIPANTS

A total of 175 adult patients with NAFLD diagnosed by abdominal ultrasonography were included in this study. Sociodemographic characteristics, anthropometric measures and metabolic, atherogenic and liver function biomarkers were assessed.

RESULTS

Results on 107 women and 68 men with NAFLD showed that 52%, 45.1% and 2.9% of patients had mild, moderate and severe NAFLD, respectively. There were significant differences in most of the anthropometric indices, serum levels of ferritin, creatinine and uric acid as well as liver enzymes, and Aspartate Aminotransferase (AST) to Platelet Ratio Index (APRI) between the genders (p<0.01). However, no significant differences were found in the glycaemic, lipid profile and atherogenic biomarkers. Both NC and neck-to-height ratio (NHtR) were significantly associated with body mass index (BMI) (p=0.018, p<0.001, respectively), waist circumference (WC) (p<0.001, p=0.044, respectively) and waist-to-hip ratio (WHR) (p<0.001, p=0.026, respectively) while results showed only a significant relationship between neck-to-waist ratio (NWR) with BMI (p<0.001) and WC (p<0.001). Among metabolic factors, there were significant and positive correlations between NC and serum haemoglobin A1c (r=0.198, p<0.001), AST (r=0.300, p<0.001), alanine aminotransferase (ALT) (r=0.348, p<0.001), ferritin (r=0.403, p<0.001) and uric acid (r=0.347, p=0.003) while AST/ALT ratio was inversely related to NC (r=-0.226, p=0.003). APRI, Lipid Accumulation Product Index and also Hepatic Steatosis Index were significantly correlated with NC, NHtR and NWR (p<0.01).

CONCLUSIONS AND RELEVANCE

NC-related indices, particularly NC and NHtR, were correlated with some metabolic and liver function biomarkers (apart from lipid profile and atherogenic factors) in patients with NAFLD.

The dietary requirement for total sulfur amino acids in adults aged ≥60 years appears to be higher in males than in females

BACKGROUND

The total sulfur amino acid (TSAA) recommendation in older adults is based on data from young adults. Physiological evidence suggests that older adults have a higher requirement than young adults.

OBJECTIVES

The objective of this study was to determine the TSAA requirement in healthy men and women aged ≥60 y.

METHODS

The TSAA requirement was determined using the indicator amino acid oxidation method with L-[1-13C]phenylalanine as the indicator. At recruitment, 15 older adults (n = 7 men and n = 8 women; BMI < 30 kg/m2) were assigned to receive 7 methionine intakes (5, 10, 15, 19, 25, 35, and 40 mg/kg/d) without dietary cysteine. Intake levels were randomly assigned to each subject. Following enrollment, 2 subjects completed 2 intakes and 3 completed 3, while the remainder completed all 7. Mean TSAA requirement was determined from oxidation of L-[1-13C]phenylalanine using a mixed-effect change-point model. The 95% CI was calculated using parametric bootstrap. To test whether breakpoints were different between men and women, the overlap in the 95% CI was calculated.

RESULTS

The mean TSAA requirement was 26.2 (Rm2 = 0.39, Rc2 = 0.89; P < 0.001) and 17.1 mg/kg/d (Rm2 = 0.22, Rc2 = 0.79; P < 0.001) for men and women, respectively. The requirement was significantly higher in men than in women (difference in CI: 9.1 ± 8.85).

CONCLUSIONS

To our knowledge, this is the first study to determine the TSAA requirement in older adults. The requirement in older women is similar to current recommendations but is 75% higher in older men. These findings are important given recommendations for increased plant protein consumption. They will help in the assessment of diet quality and provide the basis of dietary guidelines for older adults consuming a plant-based diet. This trial was registered at clinicaltrials.gov as NCT04595188.

Three-dimensional optical body shape and features improve prediction of metabolic disease risk in a diverse sample of adults

OBJECTIVE

This study examined whether body shape and composition obtained by three-dimensional optical (3DO) scanning improved the prediction of metabolic syndrome (MetS) prevalence compared with BMI and demographics.

METHODS

A diverse ambulatory adult population underwent whole-body 3DO scanning, blood tests, manual anthropometrics, and blood pressure assessment in the Shape Up! Adults study. MetS prevalence was evaluated based on 2005 National Cholesterol Education Program criteria, and prediction of MetS involved logistic regression to assess (1) BMI, (2) demographics-adjusted BMI, (3) 85 3DO anthropometry and body composition measures, and (4) BMI + 3DO + demographics models. Receiver operating characteristic area under the curve (AUC) values were generated for each predictive model.

RESULTS

A total of 501 participants (280 female) were recruited, with 87 meeting the criteria for MetS. Compared with the BMI model (AUC = 0.819), inclusion of age, sex, and race increased the AUC to 0.861, and inclusion of 3DO measures further increased the AUC to 0.917. The overall integrated discrimination improvement between the 3DO + demographics and the BMI model was 0.290 (p < 0.0001) with a net reclassification improvement of 0.214 (p < 0.0001).

CONCLUSIONS

Body shape measures from an accessible 3DO scan, adjusted for demographics, predicted MetS better than demographics and/or BMI alone. Risk classification in this population increased by 29% when using 3DO scanning.