Leonard's primary health concern is his lactose intolerance, breaking wind if he eats any dairy products.
There is weak evidence for other organic causes such as reflux esophagitus and lactose intolerance.
These include products designed for the treatment of patients with lactose intolerance or whole protein intolerance and patients who have to follow a low protein diet.
Five years later many of these people are isolated, lonely, jobless, scattered about the place and in many cases suffering from hepatitis, cataract, glaucoma, worm, tuberculosis and lactose intolerance.
Adverse effects of lactose intolerance generally occur after much higher levels of milk consumption than do adverse effects of milk allergy.
People with lactose intolerance due to small bowel disease may benefit from avoiding lactose-containing foods.
These include gastrointestinal infections, lactose intolerance, and coeliac disease.
A variety of products are available which contain milk substitutes, so those foods are still able to be consumed by individuals with a lactose intolerance.
