8. Fatigue
Fatigue is a common sign of food sensitivities and allergies, including lactose intolerance, and can be attributed to the body’s immune response to the ingestion of lactose-containing foods. When you ingest something that your body really doesn’t like, it has to work extra hard to try and process it and then eliminate it from your body as a waste product. This takes more energy, leaving less available for you throughout your day.