Final answer:
Malabsorption is a condition where digested nutrients are not absorbed by the intestinal tissues. This may occur due to food intolerances like lactose intolerance, or diseases affecting digestion. Nutrient absorption primarily happens in the small intestine.
Step-by-step explanation:
When nutrients are digested but not absorbed by the intestinal tissues, the condition is referred to as malabsorption. The process of absorption is crucial as it allows the nutrients from digested food to enter the bloodstream or lymph system and then be utilized by the body's cells. This primary absorption of nutrients occurs within the small intestine.
During the digestive process, not all substances in food can be broken down into nutrients, which results in some elements remaining in the gastrointestinal tract. These undigested substances are eventually passed out of the body as solid waste through defecation, which is the final step of digestion.
It should be noted that conditions like food intolerances, such as lactose intolerance, can limit the ability of the small intestine to digest certain foods, leading to symptoms such as stomach cramping and diarrhea. Similarly, certain diseases and conditions can impact the digestive process, leading to inadequate nutrient absorption and malnutrition.