Performance Plate

The Secret Food Intolerance Slowing You Down

An undiagnosed reaction to your pre-race meal could be hurting your athletic performance. Here's how to pinpoint—and fix—the issue.

The Secret Food Intolerance Slowing You Down

Unfortunately, needing a potty break is the least of an intolerant athlete’s concerns; battling a sensitivity issue increases inflammation, which can result in achy joints, a loss of energy, migraines, and the feeling of simply “overdoing it.” Photo: iStock

Trudging up the Colorado Rockies, Aliza Lapierre knew something was wrong. An elite ultrarunner, she was used to stomach troubles. But this was different.

“I was sluggish, I wasn’t recovering—even though I was properly trained—and food wasn’t staying in my system,” she says of her experience during the multi-day Transrockies Run a few years ago. Even worse, hives broke out over her legs, arms and stomach every time she ran. “How do you itch so many itches when you are running?”

Lapierre, now 34, had dutifully fueled her run with gluten-laden sandwiches, muesli bars, and pasta—without knowing she had a gluten intolerance.

“A food intolerance can be seriously debilitating for an athlete,” says Sarah Weber, RD, LD, a performance dietitian. Around 20 percent of adults have food intolerances, versus just one to four percent who have food allergies.

While food allergies are an immediate, potentially life-threatening immune response to food proteins, intolerances trigger more subtle symptoms that may take hours or days to appear—symptoms athletes may be tempted to dismiss as nerves such as “bloating, gas, constipation, diarrhea,” says Weber. And while gluten has become somewhat of a celebrity intolerance, spawning its own genre of packaged products, it’s hardly the only one. Athletes have found they’re intolerant of everything from coconuts to sesame seeds and bananas.

Unfortunately, needing a bathroom break is the least of an intolerant athlete’s concerns. Battling a sensitivity issue increases inflammation, which can result in achy joints, a loss of energy, migraines, and the feeling of simply “overdoing it.”

Our immune systems let loose a special type of white blood cell when we eat foods we can't tolerate. The cells are meant to attack the food, but they wind up causing chronic inflammation in the process. 

“Like soldiers on the front line, they help battle the source of inflammation but cause collateral damage affecting the endothelial—thin inner lining—of the arteries,” says sports dietitian, Bob Seebohar. “They constrict and deliver less oxygen and nutrient-rich blood to and from working muscles.” Inflammation can even trigger breathing issues, he says.

Experts have found some foods carry a higher risk of intolerance than others. “An athlete’s diet is often high in FODMAPs, a family of short-chain carbohydrates which are inherently problematic for us to digest,” says digestive disorder specialist Tamara Duker Freuman. ”They also draw water into the bowel, causing diarrhea.”

FODMAPs are increasingly blamed for causing irritable bowel syndrome, and include a long list of foods that athletes typically eat, including fructose, wheat, milk, and even broccoli. Fructose in particular, Duker Freuman says, is packed into energy gels and electrolyte beverages, and about 30 percent of Caucasians have difficulty digesting it.

Yet intolerances can also be random. Take lamb, for instance. Through process of elimination, four-time Olympic triathlete Simon Whitfield found a love of the red meat caused outbreaks of gastro and hives for a short stint during his career. “Diet is crucial to an athlete, but it’s not just what you eat, but how what you eat affects you,” says the two-time Olympic medalist. “But as an athlete you don’t get that training, or at least I didn’t.”

Things have changed. A growing list of professionals are looking into the role of food intolerances in athletic performance and they’re trying to make diagnoses easier and more concrete than the process of elimination.

Blood tests that look for white blood cell reactions to foods, such as the ALCAT test, have become popular, though they have their share of critics citing a lack of scientific evidence for their diagnostic validity. But that hasn’t stopped athletes from paying up to $1,148 out of pocket for blood testing. “When you’re an elite athlete, a three to five per cent increase in performance means a lot,” said Samy Puccio, vice president of ALCAT, which provides food intolerance testing favored by the NBL, NFL, NBA, and NHL.

For the rest of us, the promise of removing inflammation and feeling our best is enough to warrant investigation into our diets. Particularly as we get older; a combination of “age, stressors–both physical and emotional—genetics and other factors can lead to a ‘leaky gut’,” says Weber. The ‘looser’ gut wall lets through partially digested food proteins, which may be the root cause of reactions and inflammation.

The good news: Once intolerances are identified and removed, the body can bounce back. “Some cells lining the digestive tract replace in around three days,” says Weber. But full improvement requires healing your guts. “It can take months and even longer to regain a fully intact digestive and immune system.”

Though intolerances don’t affect everyone, ALCAT’s Puccio believes in the future, we should “expect performance plans where athletes get tested for food intolerances and have their performance quantified, measured and tracked.”

Suspect something in your diet is holding you back? You could fork over $399 and up for an ALCAT test. But perhaps the best, least expensive place to start is to keep a food log. It may not be as scientific, but it can still be effective. “Write down the symptoms you feel after every meal, then narrow down what’s provoking you,” says Weber. “Piece apart” the meal and eat one food at a time, isolating the suspected bandit. Working with a dietitian to conduct an elimination diet will ensure you keep it balanced.

“If you find your performance lacking, your energy levels have changed, or you’ve got new symptoms,” Puccio says, “maybe it’s time to ask what’s holding you back from getting to that next level.”

Filed To: Injury Prevention, Nutrition, Food and Drink

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