Hello and Welcome to ‘Ask A Doctor’ service. I have reviewed your query and here is my advice. Dear which food your having intolerance? Usually lactose, gluten contain food people may develop intolerance. Commonly seen in conditions like irritable bowel syndrome or infection or inflammatory bowel problems etc. Please check for above conditions through endoscopy and colonoscopy. Stool examination, biopsy etc. Avoid spicy food and alcohol, avoid smoking and caffeine drinks. Until diagnosis is confirm please avoid the food that your intolerance. If symptoms not improved please consult your doctor, he will examine and treat you accordingly. Take care.