The George Mateljan Foundation explains that nuts can be difficult to digest because they are high in fat. When nuts are eaten in moderation, however, the standard rate of digestion applies. According to the Mayo Clinic, the average rate of digestion is 53 hours.
Healthy.net states that the digestive tracts of some people have an averse reaction to nuts because of digestive disorders. Disorders that cause delays or pains in the digestive tract in response to nuts include low stomach acidity, gallstones, and gallbladder disease. These averse reactions are caused by the fat content in the nuts. Hydrochloric acid, digestive enzymes and bile produced by the gallbladder are essential for digesting nuts properly.