Association of waist circumference with muscle and fat mass in adults with a normal body mass index

Influence of body shape on health-related quality of life in Korean adults: The mediating effect of self-rated health

A Body Shape Index (ABSI) predicts mortality independent of body mass index and had a negative relationship with self-rated health (SRH), which had a positive effect on the EuroQol (EQ)-5D index. This study aimed to investigate the relationship between ABSI and the EQ-5D index and to verify the mediating effect of SRH in Korean adults. This study included 13,381 participants aged ≥20 years from the 7th (2016-2018) Korean National Health and Nutrition Examination Survey (KNHANES). The participants were classified into tertile groups based on the ABSI (T1, T2, and T3 groups). Demographic characteristics, health-related factors, ABSI, SRH, and EQ-5D scores were evaluated. Women (p<0.001), rural areas (p<0.001), married persons (p<0.001), low education level (p<0.001), low income (p<0.001), and older age (p<0.001) were higher in the T3 group. The monthly drinking (p<0.001), current smoking (p<0.001), and mental stress rates (p<0.001) were the highest in the T1 group. The overall average SRH scores and EQ-5D index were 3.08 points and 0.94 points, respectively. ABSI and SRH (r = -0.161, p<0.001) and ABSI and EQ-5D (r = -0.229, p<0.001) showed a negative correlation. However, SRH and EQ-5D scores (r = 0.433, p<0.001) were positively correlated. The overall effect of the independent variable ABSI on the dependent variable EQ-5D was -0.959. SRH partially mediated the effect of ABSI on EQ-5D (indirect effect coefficient = -0.200). These results can be used as basic data to develop strategies and programs to improve health-related quality of life by adjusting ABSI and SRH.

Weight-adjusted waist as an integrated index for fat, muscle and bone health in adults

BACKGROUND

Unhealthy body composition, including high fat mass, low muscle mass and low bone mass, is a critical health issue in adults. The weight-adjusted waist index (WWI) estimates fat and muscle mass and may have implications for bone health. We examined its association with body composition outcomes in a large Korean adult cohort.

METHODS

This study used data from the Korean National Health and Nutrition Examination Survey (2008-2011). WWI was calculated as waist circumference (cm) divided by the square root of body weight (kg). Dual-energy X-ray absorptiometry was used to measure bone mineral density (BMD), appendicular lean mass (ALM) and total body fat percentage. Unhealthy body composition was defined as combined presence of high fat mass, low bone mass and low muscle mass.

RESULTS

A total of 5983 individuals (3034 men [50.7%] and 2949 women [49.3%]; mean age: 63.5 ± 8.7 years) were included. WWI was positively correlated with total body fat percentage (r = 0.478, P < 0.001) and inversely with ALM/weight (r = -0.485, P < 0.001) and BMD at the lumbar spine (r = -0.187, P < 0.001), femoral neck (r = -0.269, P < 0.001) and total hip (r = -0.255, P < 0.001). Higher WWI quartiles correlated with lower BMD, T-scores and ALM/weight, along with increased total body fat, evident in both genders and more pronounced in women, even after adjusting for confounders. This trend remained statistically significant across WWI quartiles for all analyses (P < 0.001). Higher WWI quartiles were also significantly associated with higher odds of unhealthy body composition, with adjusted odds ratio in the highest WWI group of 18.08 (95% CI, 4.32-75.61) in men and 6.36 (95% CI, 3.65-11.07) in women. The optimal cutoff values of WWI for unhealthy body composition were 10.4 cm/√kg in men and 10.5 cm/√kg in women.

CONCLUSIONS

In community-dwelling adults, high WWI values are associated with unfavourable body composition outcomes, indicating high fat mass, low muscle mass and low bone mass. WWI can potentially serve as an integrated index of body composition, underscoring the need for further research to validate its use in clinical settings.

Adherence to the Mediterranean Diet Is Associated with Health-Related Quality of Life and Anthropometric Measurements in University Professors

The main objective of this study was to assess the relationship between Mediterranean diet (MD) adherence and health-related quality of life (HRQOL) according to the anthropometric measurements of teaching and research staff (TRS) at the University of Granada (UGR), Spain. This diagnostic, non-experimental, cross-sectional, and observational study was performed on university lecturers (65 women and 62 men) using a correlational descriptive methodology. The lecturers' anthropometric measurements were taken, while MD adherence was determined using the PREvention with MEDiterranean diet (PREDIMED) questionnaire. The Short Form Health Survey (SF-36) was used for measuring HRQOL. Better results for body composition were associated with improvements in the physical and mental dimensions and MD adherence. Statistically significant differences were found between sexes, with men showing higher values for weight, height, waist circumference, BMI, waist/hip ratio (WHR), muscle mass, and systolic and diastolic pressure than women. Similarly, MD adherence was positively correlated with vitality (r = 0.233; p = 0.009), social functioning (r = 0.229; p = 0.008), and the mental component summary (r = 0.205; p = 0.021). The regression model determined that the mental component summary (β = 0.239, p = 0.041), diastolic pressure (PD) (β = -0.473, p < 0.000), fat percentage (FP) (β = -0.241, p = 0.004), and age (β = -0.231, p = 0.022) significantly predicted MD adherence. The results obtained in this study suggest that healthy dietary patterns such as the MD and an optimum body composition contribute to an improved HRQOL.

Development and Validation of Waist Girth-Based Equations to Evaluate Body Composition in Colombian Adults: Rationale and STROBE-Nut-Based Protocol of the F20 Project

Waist girth (WG) represents a quick, simple, and inexpensive tool that correlates with excess of fat mass in humans; however, this measurement does not provide information on body composition. The evaluation of body composition is one of the main components in the assessment of nutritional status. Indeed, the use of anthropometry-based equations to estimate body fat and fat-free mass is a frequent strategy. Considering the lack of validation in the Colombian population, the aim of this research study (the F20 Project) is to externally validate WG-based equations (e.g., relative fat mass), and also to develop and validate new models that include WG to estimate body composition in Colombian adults compared to DXA. This cross-sectional study will be carried out following the guidelines for Strengthening the Reporting of Observational Studies in Epidemiology-Nutritional Epidemiology (STROBE-nut). Using stratified probabilistic sampling, the study population will be adults with different levels of physical activity residing in Medellín and its metropolitan area. The results of this study will not only validate the estimation performance of the current WG-based equations, but they will also develop new equations to estimate body composition in the Colombian population. This will improve professional practice in health, exercise, and sports sciences (ClinicalTrials.gov ID #NCT05450588).