Although there is some evidence that total dietary antioxidant capacity (TDAC) is inversely associated with the presence of obesity, no longitudinal studies have been performed investigating the effect of TDAC on comprehensive measures of body composition over time. In this study, we included 4595 middle-aged and elderly participants from the Rotterdam Study, a population-based cohort. We estimated TDAC among these individuals by calculating a ferric reducing ability of plasma (FRAP) score based on data from food-frequency questionnaires. Body composition was assessed by means of dual X-ray absorptiometry at baseline and every subsequent 3-5 years. From these data, we calculated fat mass index (FMI), fat-free mass index (FFMI), android-to-gynoid fat ratio (AGR), body fat percentage (BF%) and body mass index (BMI). We also assessed hand grip strength at two time points and prevalence of sarcopenia at one time point in a subset of participants. Data were analyzed using linear mixed models or multinomial logistic regression models with multivariable adjustment. We found that higher FRAP score was associated with higher FFMI (0.091 kg/m2 per standard deviation (SD) higher FRAP score, 95% CI 0.031; 0.150), lower AGR (-0.028, 95% CI -0.053; -0.003), higher BMI (0.115, 95% CI 0.020; 0.209) and lower BF% (-0.223, 95% CI -0.383; -0.064) across follow-up after multivariable adjustment. FRAP score was not associated with hand grip strength or sarcopenia. Additional adjustment for adherence to dietary guidelines and exclusion of individuals with comorbid disease at baseline did not change our results. In conclusion, dietary intake of antioxidants may positively affect the amount of lean mass and overall body composition among the middle-aged and elderly.
Protein supplementation has shown to improve muscle mass in older adults. However, its effect may be influenced by supplementation dose, frequency and timing. This systematic review aimed to assess the effect of dose, frequency and timing of protein supplementation on muscle mass in older adults. Five databases were systematically searched from inception to 14 March 2023, for randomised controlled trials investigating the effect of protein supplementation on muscle mass in adults aged ≥65 years. Random effects meta-analyses were performed, stratified by population. Subgroups were created for dose (≥30 g, <30 g/day), frequency (once, twice, three times/day) and timing of supplementation (at breakfast, breakfast and lunch, breakfast and dinner, all meals, between meals). Heterogeneity within and between subgroups was assessed using I 2 and Cochran Q statistics respectively. Thirty-eight articles were included describing community-dwelling (28 articles, n=3204, 74.6±3.4 years, 62.8 % female), hospitalised (8 articles, n=590, 77.0±3.7 years, 50.3 % female) and institutionalised populations (2 articles, n=156, 85.7±1.2 years, 71.2 % female). Protein supplementation showed a positive effect on muscle mass in community-dwelling older adults (standardised mean difference 0.116; 95 % confidence interval 0.032–0.200 kg, p=0.007, I 2=15.3 %) but the effect did not differ between subgroups of dose, frequency and timing (Q=0.056, 0.569 and 3.084 respectively, p>0.05). Data including hospitalised and institutionalised populations were limited. Protein supplementation improves muscle mass in community-dwelling older adults, but its dose, frequency or timing does not significantly influence the effect.
MULTIFILE
Rationale: Diagnosis of sarcopenia in older adults is essential for early treatment in clinical practice. Bio-electrical impedance analysis (BIA) may be a valid means to assess appendicular lean mass (ALM) in older adults, but limited evidence is available. Therefore, we aim to evaluate the validity of BIA to assess ALM in older adults.Methods: In 215 community dwelling older adults (age ≥ 55 years), ALM was measured by BIA (Tanita MC-780; 8-points) and compared with dual-energy X-ray absorptiometry (DXA, Hologic Discovery A) as reference. Validity for assessing absolute values of ALM was evaluated by: 1) bias (mean difference), 2) percentage of accurate predictions (within 5% of DXA values), 3) individual error (root mean squared error (RMSE), mean absolute deviation), 4) limits of agreement (Bland-Altman analysis). For diagnosis of low ALM, the lowest quintile of ALM by DXA was used (below 21.4 kg for males and 15.4 for females). Sensitivity and specificity of detecting low ALM by BIA were assessed.Results: Mean age of the subjects was 71.9 ± 6.4, with a BMI of 25.8 ± 4.2 kg/m2, and 70% were females. BIA slightly underestimated ALM compared to DXA with a mean bias of -0.6 ± 0.2 kg. The percentage accurate predictions was 54% with RMSE 1.6 kg and limits of agreements −3.0 to +1.8 kg. Sensitivity was 79%, indicating that 79% of subjects with low ALM according to DXA also had low ALM with the BIA. Specificity was 90%, indicating that 90% of subjects with ‘no low’ ALM according to DXA also had ‘no low’ ALM with the BIA.Conclusions: This comparison showed a poor validity of BIA to assess absolute values of ALM, but a reasonable sensitivity and specificity to diagnose a low level of ALM in community-dwelling older adults in clinical practice.Disclosure of interest: None declared.
Along with the rapidly growing number of disabled people participating in competitive sports, there is an increased need for (para)medical support in disability sports. Disabled athletes experience differences in body composition, metabolism, training load and habitual activity patterns compared with non-disabled athletes. Moreover, it has been suggested that the well-recognized athlete triad, and low energy availability and low bone mineral density in particular, is even a greater challenge in disabled athletes. Therefore, it is not surprising that sport nutritionists of disabled athletes have expressed an urgency for increased knowledge and insights on the nutritional demands of this group. This project aims to investigate energy expenditure, dietary intake, body composition and bone health of disabled athletes, ultimately leading to nutritional guidelines that promote health and optimal sports performance for this unique population. For this purpose, we will conduct a series of studies and implementation activities that are inter-related and build on the latest insights from sports practice, technology and science. Our international consortium is highly qualified to achieve this goal. It consists of knowledge institutes including world-leading experts in sport and nutrition research, complemented with practical insights from nutritionists working with disabled athletes and the involvement of athletes and teams through the Dutch and Norwegian Olympic committees. The international collaboration, which is a clear strength of this project, is not only focused on research, but also on the optimization of professional practice and educational activities. In this regard, the outcomes of this project will be directly available for practical use by the (para)medical staff working with disabled athletes, and will be extensively communicated to sport teams to ensure that the new insights are directly embedded into daily practice. The project outcomes will also be incorporated in educational activities for dietetics and sport and exercise students, thereby increasing knowledge of future practitioners.
