To avoid digestive disorders related to endurance sports, or to improve their performance, many athletes, like Djokovic, have removed gluten from their diet. According to a latest survey, 41% of athletes without celiac disease adopted a gluten-free diet (1).
Is this justified?
Is Gluten really the culprit?
Let’s see !
What is gluten
Gluten is a protein made up of gliadins and prolamins found in wheat, barley, oats and rye, as well as in their derivatives.
Oats are not usually a problem, but this cereal is often “contaminated” with wheat.
Therefore, it’s important to choose certified gluten-free oats if you want to eliminate gluten from your diet.
Why would you eliminate gluten?
Gluten, or at least its compounds, is only partially digested.
Gluten will activate zonulin which cand lead to a leaky gut. The inflammatory effect of gluten will add to the stress on the body (physical activity is stressful for the body).
Limiting gluten could be beneficial. However, the positive effects shown by athletes who made this choice also come from the fact that they will pay more attention to their diet.
If athletes don’t switch to processed gluten-free products, their diet will be higher in carbohydrate vegetables and other healthy foods.
Gluten free or FODMAP diet, what studies say
Studies have shown that a low FODMAP diet would be just as beneficial, if not more, than cutting off gluten (1).
However, reducing foods high in FODMAPs induces at the same time a decrease in the consumption of foods containing gluten.
A recent study based on a survey indicated that 55% of athletes (n = 910) report having eliminated at least one food rich in one of the FODMAPs category in attempt to reduce their digestive disorders.
85% of them reported improvement in their symptoms.
Lactose was the main eliminated one (86.5%), followed by GOS (23.9%), fructose (23.0%), fructans (6.2%) and polyols (5.4% ) (2).
The low-FODMAP diet seems to be also beneficial to athletes who do not have an irritable bowel syndrome but who experience digestive disorders during efforts. (1)
(1) Dana M. Lis (janvier 2019) Exit Gluten-Free and Enter Low FODMAPs: A Novel Dietary Strategy to Reduce Gastrointestinal Symptoms in Athletes Sports Medicinevolume 49, pages87–97. Exit Gluten-Free and Enter Low FODMAPs: A Novel Dietary Strategy to Reduce Gastrointestinal Symptoms in Athletes | SpringerLink
(2) Dana Lis, Kiran D K Ahuja, Trent Stellingwerff, Cecilia M Kitic, James Fell (septembre 2016). Food avoidance in athletes: FODMAP foods on the list.
Appl Physiol Nutr Metab;41(9):1002-4. Food avoidance in athletes: FODMAP foods on the list – PubMed (nih.gov)