Seasonal changes in midlife women’s percentage body fat: A 1-year cohort study

Authors: Nelson, Alese; Casperson, Shanon; JAHNS, LISA - National Institute Of Food And Agriculture (NIFA); PALMER, DANIEL - University Of North Dakota; Roemmich, James

Submitted to: Journal of Aging Research & Lifestyle
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/12/2022
Publication Date: 7/1/2022
Citation: Nelson, A.M., Casperson, S.L., Jahns, L., Palmer, D., Roemmich, J.N. 2022. Seasonal changes in midlife women’s percentage body fat: A 1-year cohort study. Journal of Aging Research & Lifestyle. 11:20-25. https://doi.org/10.14283/jarlife.2022.4.
DOI: https://doi.org/10.14283/jarlife.2022.4

Interpretive Summary: Scientists at the USDA-ARS Grand Forks Human Nutrition Research Center examined whether mid-life women’s age and their seasonal changes in sedentary activity, physical activity, energy intake, and depressed mood predicted changes in their body composition. They found that greater age and summer to fall increases in energy intake predicted seasonal increases percentage body fat. To minimize increases in %BF and maintain health, midlife women, particularly older women, should be encouraged to pay extra attention to their diet in the fall months.

Technical Abstract: Objectives: The purpose of this longitudinal, observational study was to examine whether age and seasonal changes in sedentary activity (sedAct), moderate-to-vigorous physical activity (MVPA), energy intake (EI), and depressed mood predict changes in body composition among midlife women. We hypothesized that reductions in MVPA and increases in sedAct, EI, and depressed mood in winter, along with greater baseline age would predict increases in percentage body fat (%BF) across seasons. Methods: Participants included 52 midlife women (aged 40-60 years) who were observed over the course of one year. Percentage body fat measures were obtained via whole body Dual Energy X-ray absorptiometry. Participants were scanned once per season. We measured EI using the ASA24®. We used a GTX3 accelerometer to measure physical activity. Each season, participants wore the monitors for 7 days, 12 hours per day. We used the depression subscale of the Profile of Mood States. Results: Results of hierarchical multiple regression (MR) analyses showed that age increases and summer to fall increases in EI predicted seasonal increases in %BF. Repeated measures ANCOVA revealed that summer-to-winter increases in %BF are not reversed by spring. Conclusions: To minimize increases in %BF and maintain health, midlife women, particularly older women, should be encouraged to pay extra attention to their diet in the fall months.