Diet quality for sodium and vegetables mediate effects of whole food diets on 8-week changes in stress load

Authors: SOLTANI, HODA - University Of California, Davis; Keim, Nancy; Laugero, Kevin

Submitted to: Nutrients
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/27/2018
Publication Date: 11/1/2018
Citation: Soltani, H., Keim, N.L., Laugero, K.D. 2018. Diet quality for sodium and vegetables mediate effects of whole food diets on 8-week changes in stress load. Nutrients. 10(11):1606. https://doi.org/10.3390/nu10111606.
DOI: https://doi.org/10.3390/nu10111606

Interpretive Summary: Chronic or repeated psychological stress is a growing health concern. Too much stress has been linked to diseases of the brain and body. These types of diseases include type 2 diabetes, heart disease, major depression, and cognitive decline. However, some people are affected by stress more than others. More research is needed to understand the factors that affect how the brain and body react to stress, and how these factors influence the link between stress exposure and increased risk for chronic disease. The foods one eats may affect how the brain and body react to stress, and stress has also been shown to influence the types of foods one chooses to eat. A key question that needs to be addressed is how whole food diets, such as those based on the Dietary Guidelines for Americans (DGA), influence chronic psychological stress and its related physiological response. To better understand the effects of whole diets on how the body and brain respond to stress, we examined psychological and physiological stress responses to a DGA based diet. A randomized, double-blind, controlled 8-wk intervention was conducted in overweight and obese women randomly assigned to one of two diet groups: a diet considered to be healthy and based on the 2010 DGA or a diet higher in saturated fat, added sugar, and sodium. The Perceived Stress Scale, which is a questionnaire asking about feelings of stress over the past month, and allostatic load, which is an indicator of the body’s physiological status or health, were used to assess stress in this study. Results showed that improvements in vegetable and sodium consumption were related to lower stress. This study provides further evidence for the health benefits of maximizing vegetable and minimizing sodium consumption. The new findings in this study also further extend a growing body of support for the beneficial effects of a healthy diet on mental health.

Technical Abstract: Very little is known about how whole food diets, such as those based on the Dietary Guidelines for Americans (DGA), influence perceived stress and overall chronic stress load. To better understand the effects of whole diets on chronic stress load, we examined in a randomized control trial effects of a DGA based diet on markers of psychological and physiological stress. A randomized, double-blind, controlled 8-wk intervention was conducted in overweight and obese women randomly assigned to one of two diet groups, a diet based on the 2010 DGA or a diet based on a Typical American Diet (TAD). The Perceived Stress Scale and allostatic load were used to assess stress load. While 8-wk change in both markers of stress did not differ between the DGA and TAD groups, there were strong inverse associations between 8-wk change in stress and improvements in diet quality (lower sodium and higher vegetable consumption), and these dampening effects of including less sodium and more vegetables in the diet appear to have blunted or masked otherwise stress-inductive effects of shifting to a diet of higher quality (DGA) for 8 weeks. This study provides further evidence for the health benefits of maximizing vegetable and minimizing sodium consumption. Given the known detrimental health risks of chronic stress on the body and brain these findings may have important clinical implications.