Energy intake and season interact to influence physiological stress load among midlife women

Authors: Laugero, Kevin; PAUL, DAVID - University Of Idaho; JAHNS, LISA - National Institute Of Food And Agriculture (NIFA)

Submitted to: Stress: The International Journal on Biology of Stress
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/10/2021
Publication Date: 6/7/2021
Citation: Laugero, K.D., Paul, D., Jahns, L. 2021. Energy intake and season interact to influence physiological stress load among midlife women. Stress: The International Journal on Biology of Stress. https://doi.org/10.1080/10253890.2021.1931106.
DOI: https://doi.org/10.1080/10253890.2021.1931106

Interpretive Summary: Chronic mental or emotional stress can lead to persistent changes in an individual’s physiology and other systems in the body. Allostatic load is a clinical marker commonly used to assess these changes in the body, and more allostatic load has been linked to chronic disease risk. The factors linking allostatic load and chronic disease risk are unknown, but one possible factor is poor diet or dietary habits. Chronic stress and allostatic load have been shown to associate with poor diet or diet patterns. However, an important question that is still to be sufficiently addressed is whether this relationship between allostatic load and diet varies with season. Our observational study tested in fifty-two women aged 40-60 years for seasonal differences in the relationship between allostatic load and daily consumption of total calories, carbohydrates, fat, and protein. We found that higher allostatic load associated with consumption of significantly more calories, carbohydrates, and fat. However, these relationships were only observed during the summer and winter seasons, but not during fall or spring. Our results suggest that some women may be more vulnerable to the effects of persistent stress on eating behavior during certain times of the year. On the other hand, it is also possible that some women may be more susceptible to the effects of energy overconsumption on allostatic load and, therefore, disease risk during certain seasons. More research is needed to better understand the direction of this relationship between allostatic load and diet, and whether this relationship influences disease risk.

Technical Abstract: Allostatic load (AL) is an index that measures physiologic stress associated with chronic disease risk. While AL is cross-sectionally associated with dysregulated eating and poor diet quality, it is unknown whether these associations persist seasonally over times of increased or decreased stress. The objective of this study was to calculate and test differences of AL in a sample of mid-life women across each of four seasons, and examine seasonal relationships of energy and macronutrients with AL. Potential covariates were also included in the analysis. This study had an observational cohort design and was conducted in fifty-two women aged 40-60y from the Life in All Seasons study. Women completed an online 24-hr recall every 10 days and had components of allostatic load measured seasonally. Women were from the greater Grand Forks, ND catchment area and were followed for one year between July 2012 and July 2014. Mixed linear models with subject as a random effect were used to test for effects of season on the association between AL and energy and macronutrient intake. AL, energy and macronutrient intake, and covariates did not vary by season (P = 0.05). However, there was a significant interaction between season and energy consumption (P = 0.008). The association coefficients were positive for AL and energy intake in summer (P = 0.001) and winter (P = 0.005). The statistical covariates, which included physical activity, age, and BMI, were not statistically significant in the model. Our results suggest that the relationship between energy intake and AL varies by season, which may make some individuals more vulnerable to stress-related eating behavior during certain times of the year. Therefore, it might be helpful for Registered Dietitian-Nutritionists to be aware of possible seasonal fluctuations in stress-related eating in their clients.