Sports Foods Might Cause Up to 40% of Gastrointestinal Distress in Athletes

Sports foods and drinks often rely on fructose as a key carbohydrate fuel ingredient. Yet studies show that up to 40% of athletes have fructose malabsorption, which causes gas, bloating, and other gross GI issues.

Sound familiar?

Fructose is a FODMAP carbohydrate and it’s very common among processed sports foods, even all-natural ones. Studies show that the all-too-familiar gas, bloating, and gross GI issues so many athletes experience might be caused by the fructose found in their sports drinks, bars, and gels.


Under normal circumstances, fructose is absorbed through the gut wall and transported to the liver for processing. Sometimes a particular protein needed for this normal digestion is missing, and fructose sugars end up in the large intestine instead.

Once in the large intestine, gut bacteria ferment the fructose and you know what happens next: gas with bloating, diarrhea, flatulence, and the urgency to rush to a bathroom.

Some degree of fructose malabsorption may be present in as much as 30-40% of athletes. When you consider that sports foods and drinks often use fructose as a carbohydrate source, they could potentially be to blame for some of the GI distress that frustrates so many athletes.

Fructose malabsorption can be made worse by a variety of factors. For more, check out The Athlete’s Fix.

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