Gels Hurt Your Stomach? Power Through Long Runs With This Natural Fuel Instead, Dietitian Says

Fuel is a nonnegotiable for endurance athletes like runners. Gels from brands like Gu, Huma, and Honey Stinger have long been the go-to because they deliver quick carbs that help maintain blood sugar levels and performance during strenuous activities lasting more than one to two hours. Experts typically recommend 30 to 60 grams of carbohydrates per hour, which comes out to about one to three gels. This keeps energy levels up as glycogen stores in the muscles and liver begin to drop. Though convenient, many athletes report gastrointestinal issues when using them. That’s why some athletes are turning to simpler alternatives, like honey, for a quick, natural source of fuel.

"During exercise like running, blood flow to the digestive tract is reduced so energy can be focused on the activity," says Avery Zenker, R.D., at CrohnsandColitisTeam. "Digestion becomes less of a priority for the body when we’re engaged in a vigorous activity like running. The gut becomes more susceptible to potential stressors and inflammation, which can cause foods like gels to trigger digestive symptoms."

Due to reduced blood flow to the digestive tract during running, the gut's ability to digest and absorb food may be reduced. Rapidly consuming quick carbs like gels can overwhelm the gut, especially during intense or prolonged efforts. Many gels also have high osmolality, containing a high concentration of sugar relative to water, which can attract fluid into the gut and trigger uncomfortable symptoms like cramping, bloating, or diarrhea.

Related: A Pro Marathon Runner Shares the Habits That Make Long Runs Feel Easier

Honey has emerged as a natural, fast-absorbing carb swap over popular gels. It's primarily composed of two sugars, glucose and fructose, as well as smaller amounts of other carbohydrates, similar to what can be found in gels. Studies have found that honey is similar or even identical to gels as a carbohydrate source for exercise performance.

Plus, honey is often well-tolerated and may cause less digestive discomfort compared to gels. However, it’s worth noting that honey is a high-FODMAP food, which may trigger digestive issues in people who are sensitive to FODMAPs.

"The glucose and fructose composition of honey can vary," Zenker says. "Honey with a higher ratio of fructose to glucose has a lower glycemic index, so the blood sugar response may be slightly [steadier] and prolonged than a higher glucose honey or gel. This could translate to a more sustained energy availability."

If honey doesn't tickle your fancy, there are plenty of viable alternatives to gels, like sports drinks, candy, fruit, fruit juice, and dried fruit. The form of carbohydrates doesn’t matter as much, as long as an adequate quantity of carbohydrates and water are consumed. As is standard protocol, don’t wait until race day to try anything new on your run—including honey or other fuels.

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