Are Your Tummy Ills All in Your Head?

Are your tummy troubles all in your head? Yes. And no. There’s a reason why, when you’re upset, you feel a knot in the pit of your stomach. "The brain and the digestive tract share many of the same nerve connections," says Douglas A. Drossman, M.D., a gastroenterologist and psychiatrist and co-director of the University of North Carolina Center for Functional GI and Motility Disorders in Chapel Hill. It’s because, in the womb, the nerves that eventually separate into the brain, spinal cord and nerves of the intestine all have the same beginnings and remain interconnected.

Mental stress delivers a one-two punch to our digestive systems. First it causes the release of cortisol and adrenaline, hormones that not only divert energy to your muscles (so you can fight—or flee!), but also slow digestion. For momentary bouts of stress, that’s a good thing (you want to use your energy to escape the bear, not digest your lunch), but when stress is chronic those same hormones can make your digestive system sluggish, leading to constipation. In addition, chronic stress can alter the release of neurotransmitters like serotonin, which promotes relaxation. And because 80 percent of your body’s serotonin is located in your gut, it’s no wonder that when too much is released it can keep you running to the bathroom, while too little can make you irregular.

Luckily, science suggests that, when stress strikes, reaching for certain foods can soothe your psyche and your "stomach." Here are three to get things back on track:

Oatmeal: This comforting grain is packed with fiber, which helps regulate digestion—slowing things down when they’re moving too fast and speeding things up when they’re sluggish. The fiber in oatmeal also guards against dips in blood glucose that can leave you cranky and lethargic.

Yogurt: You’ve heard that probiotics (good-for-you bacteria in foods like yogurt) can improve digestive health—and there’s some evidence they might. Now a British Journal of Nutrition study indicates they may alleviate stress as well. Study participants who took a probiotic supplement felt less stress, depression and anxiety than those who received a placebo. "Probiotics are very strain-specific, meaning that each strain has unique and distinct benefits," says D. Milton Stokes, M.P.H., R.D., co-author of Flat Belly Diet! for Men (Rodale, 2009). "While this study looked at only two specific strains [that aren’t currently available to consumers in foods], it provides encouraging evidence that probiotics may have a beneficial impact on the mind-gut connection."

Fatty fish: Stress can trigger an increase in compounds called cytokines that promote inflammation, which can worsen digestive ills. Eating more EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid)—two omega-3 fats found most commonly in oily fish, such as salmon, herring and sardines—can help relieve inflammation linked to tummy troubles, according to a 2005 Scandinavian Journal of Nutrition study.