Celiac disease is an oft-overlooked diagnosis that can cause a wide constellation of common symptoms, including fatigue, decreased exercise tolerance and a variety of IBS-like gastrointestinal manifestations.
Athletes in particular should suspect this with an unexplained loss in performance or worsening fatigue. It’s diagnosed with a simple blood test.
Because there’s no known medication for treatment, little has been spent in researching new cures apart from a gluten-free diet. That’s unfortunate.