Another mechanism linking stress and obesity
Researchers at Ohio University have found that stressful events occurring during the day before a single consumption of fat-rich foods can slow down metabolism and possibly contribute to the appearance of fat deposits.
In total, 58 women participated in the study, whose average age was 53 years. Each of them was given three standard sets of foods that they ate during the day preceding the visit to the clinic. Before the visit, the women had to abstain from eating for 12 hours.
Upon admission to the clinic, they filled out questionnaires to assess the presence of depressive symptoms and the level of physical activity. The researchers also interviewed them separately for the stressful events of the previous day. Most of the described stressful situations were interpersonal in nature (conflicts with colleagues or spouses, disagreements with friends, problems with children) or were related to the workload at work.
After that, the women were offered to eat a fat-rich set of products consisting of eggs, turkey sausage, cookies and sauce for 20 minutes. In total, these products contained 930 calories (at least 1/3 of the recommended daily allowance), including 60 grams of fat, which is approximately equivalent to a "two-story" hamburger and a portion of French fries served in fast food establishments.
The women in the control group ate food with a similar calorie content, but instead of saturated fatty acids, it contained sunflower oil containing monounsaturated fatty acids, which are considered beneficial for health.
Within 30 minutes after the end of the meal, the women rested, and the researchers assessed their energy expenditure – the number of calories burned when splitting nutrients for energy. The participants' metabolic rate was assessed every 20 minutes for 7 hours after the end of the meal. To do this, the researchers used equipment that measures the oxygen and carbon dioxide content in the inhaled and exhaled air. In addition, they repeatedly analyzed the content of triglycerides, cortisol, insulin and glucose in the women's blood.
On average, regardless of the type of fat contained in the food, women who noted one or more stressful events during the previous 24 hours burned 104 kilocalories less during 7 hours of observation than participants who did not experience stress. According to the authors, within a year this difference can result in an increase in body weight by almost 5 kg.
Women who experienced stressful situations also recorded higher levels of insulin, which contribute to fat deposition, and a reduced rate of fat oxidation in order to obtain energy.
According to the head of the study, Professor Jean Kiecolt-Glaser, all this means that over time stressful situations can lead to the accumulation of excess weight. It has long been known that the "jamming" of stress with high–calorie foods is a common phenomenon. At the same time, the observations made revealed another mechanism by which chronic stress contributes to an increase in body weight – a decrease in the metabolic rate.
The authors also note that, perhaps, the revealed pattern does not apply to men, as a rule, who have more muscle tissue, which affects the metabolism. In any case, the data obtained are an additional motivation to keep useful products on hand that will allow you to "jam" stress without compromising your figure and health.
Article by Janice K. Kiecolt-Glaser et al. Daily Stressors, Past Depression, and Metabolic Responses to High-Fat Meals: A Novel Path to Obesity is published in the journal Biological Psychiatry.
Evgeniya Ryabtseva
Portal "Eternal youth" http://vechnayamolodost.ru based on the materials of Ohio State University:
Weighty Issue: Stress and High-Fat Meals Combine to Slow Metabolism in Women.
15.07.2014