How to Fuel a Marathon With a Sensitive Stomach

“Bananas are great because they’re easy to digest and considered non-irritating for the stomach and upper gastrointestinal tract,” says Julie Upton, M.S., R.D., cofounder of Nutrition - Weight Loss. The high-fiber fruit not only keeps the system regular and aids in recovering from diarrhea, but the vitamin B6 also reduces bloating caused by fluid retention and the magnesium helps to relax muscles.

Advertisement - Continue Reading Below more nausea because there’s nothing in the system to absorb stomach acid. Upton suggests nibbling on white toast or soda crackers every few hours since the starches from these simple carbohydrates “lack fiber, protein, and fat—all of which slow digestion and sit in your stomach longer.” The result: stool with some extra bulk.

Upton’s top two choices belong to the BRAT (bananas, rice, applesauce, and dry toast) diet, “the clinical diet plan registered dietitians use when patients have acute diarrhea or nausea.”

“High-fat sources of protein like processed or red meats and fried food can cause reflux—especially if you’re consuming large amounts late at night,” London says. “Eggs are an easier-to-digest alternative and an easy way to meet your protein needs without getting too full, too fast.” She recommends scrambling them with a drizzle of cooking oil or butter for a light dinner when you need something simple.

We may earn commission from links on this page, but we only recommend products we back and prevent any future intestinal issues. “Soluble fiber from oats draws water into your digestive tract and moves food through your body,” London says. Aim to gradually hit at least 25 to 35 grams of total fiber per day, but don’t overdo it. “Both hunger and overeating can make nausea, bloating, abdominal pain, and gas even worse,” she adds.

Prebiotic foods—produce, whole grains, pulses, nuts, and seeds—can help “fuel” friendly gut bacteria in your GI tract, London explains. By stimulating that “microbiota,” prebiotics boost intestinal immunity and prevent inflammation, diarrhea, and other GI problems, according to 2013 research by the How to Fuel a Marathon With a Sensitive Stomach. Stock up on tomatoes, chicory, onions, asparagus, and wheat for the best benefits.

Foods that are rich in calcium, magnesium, and potassium also reduce belly bloat by balancing out sodium. Plus, research has linked diets high in these nutrients with smaller waists in those genetically predisposed to carrying weight in their midsections. Add yams Prime Day Running Fuel Deals spinach to your repertoire to help bust bloating.

“Ginger tea, ginger supplements, ginger lozenges—ginger has been shown in some studies to help alleviate nausea and vomiting,” Upton says. “In fact, it is often recommended for morning sickness and for chemotherapy-induced nausea.”

Just one word of caution: “While it’s safe for adults, ginger should not be used to treat a child’s gastrointestinal illness,” she adds.