Question: how do you know if you can't eat gluten?
Answer: Bloating. Bloating is when you feel as if your belly is swollen or full of gas after you've eaten. ... 
Diarrhea, Constipation and Smelly Feces. ... 
Abdominal Pain. ... 
Headaches. ... 
Feeling Tired. ... 
Skin Problems. ... 
Depression. ... 
Unexplained Weight Loss.