The Number of Calories Each Stressful Incident Costs You

You know that stress can negatively impact your sleep habits and your sex life—and if you're up on the latest research, you may have also heard that it's not great for your waistline. But new research sheds some light on how exactly anxiety may lead to weight gain: Women burn fewer calories in the 24 hours following stressful events, according to a new study from the journal Biological Psychiatry.  

For the study, researchers from Ohio State University interviewed 58 healthy women about the stressors they'd experienced in the previous 24 hours, then served them a high-fat meal that included eggs, turkey sausage, biscuits, and gravy (the meal came to 930 calories and 60 grams of fat). Afterward, researchers tested the women's metabolic responses—how quickly they burned calories and fat—for the next seven hours.

Although all of the women simply rested after eating, those who struggled with stressors the previous day expended significantly less metabolic energy than those who reported no stress; on average, they burned 104 fewer calories. At this rate, they could gain 11 extra pounds per year—without changing any other diet and exercise habits.

Why? In addition to slower post-meal energy expenditure, women who reported more stressors also experienced lower fat oxidation and higher insulin production. The less fat your body oxidizes, the more fat you store and the higher your risk is for obesity; high insulin levels also enhance fat storage.

Can't drop everything and spend 24/7 at the yoga studio or on the beach? Don't sweat it. "We know we can't always avoid stressors in our life," the researchers say in the text of the study. "But one thing we can do to prepare for that is to have healthy food choices in our refrigerators and cabinets so that when those stressors come up, we can reach for something healthy rather than going to a very convenient but high-fat choice."

The takeaway: If you're trying to avoid weight gain, prep your kitchen to promote healthy eating. Pack some one-ounce portions of nuts for when you're on-the-go, and slice up some fresh fruit in the beginning of the week so it's ready when you are. And about that anxiety? Make sure to pay attention to any stress symptoms, and try out some quick and easy de-stressing activities.

MORE: An Unexpected Way to Gain Control Over Your Hunger 

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