Stress may cancel out benefits of healthy diet, study suggests

Stressful events may cancel out the benefits of eating healthy fats, a new study suggests, but researchers noted their findings don’t give people permission to eat whatever they want when they’re feeling anxious.

Knowing that both diet and stress can alter inflammation in the body, researchers at The Ohio State Wexner Medical Center sought to understand the relationship among stress, diet and inflammatory markers measurable in the bloodstream.  Chronic inflammation is linked with health problems like heart disease, diabetes and rheumatoid arthritis.

Researchers studied 38 breast cancer survivors and 20 other women, all of who visited Ohio State on two different days and ate one of two meals while there. The researcher stemmed from a study looking at high-fat diets and depression in cancer survivors. One meal was a breakfast of biscuits and gravy made mostly with saturated fat. The other meal was nearly identical but made primarily with monounsaturated sunflower oil.

The women, who had an average age of 53, took the Daily Inventory of Stressful Events questionnaire to determine if they were under stress, and researchers asked them about the previous day’s experiences. A stressful event did not include minor irritants, but did include having to clean up paint a child spilled on the floor, and struggling to help a parent with dementia who was resisting help.

“They’re not life-shattering events, but they’re not of the hangnail variety either,” Jan Kiecolt-Glaser, lead author of the study and a professor of psychiatry and psychology, said in a news release.

During the study period, the women’s blood was drawn multiple times, and researchers looked at two markers of inflammation and two markers that predict a greater likelihood of plaque forming in the arteries.

Following the saturated fat meal, all four unhealthy markers were higher than after the sunflower oil meal. However, when women reported being under stress the previous day, the difference disappeared— making eating a breakfast with “bad fat” the same as eating one with “good fat.” The readings for those who ate saturated fat did not change after a stressful event.

Researchers believe their study is the first to show that stress has the potential to cancel out benefits of choosing healthier fats, but they noted that inflammation builds up over time to contribute to disease. Therefore, they advised against eating unhealthy food while under stress. More important, study authors said, individuals should aim to eat healthier choices every day, so when stress arises, they are starting in a better place.

The study was published Tuesday in Molecular Psychiatry.