The type of malabsorption that occurs is based on the specific nutrient not being absorbed during digestion. Multiple types of malabsorption may occur at the same time. For example, celiac disease and short bowel syndrome are responsible for the malabsorption of fats, protein, carbohydrates, vitamins and minerals.

Types of malabsorption include:

• Fat malabsorption. Inability to absorb fats (found in foods like butter, margarine, oils, meat, fried and processed foods) during digestion. Steatorrhea (fat buildup in stool) is a sign of fat malabsorption. Unexplained weight loss also usually occurs with this type of malabsorption. The inability to absorb fats often occurs in combination with other types of malabsorption and in many conditions that involve malabsorption. The digestion and absorption of fats is a more complex process than that of protein or carbohydrates. This increases the possibility of absorption problems because each step in the process is essential.
  
  
• Carbohydrate malabsorption. Inability to absorb carbohydrates (sugar, starches and fiber found in foods such as bread, potatoes, rice, fruits and vegetables) during digestion. Other carbohydrates include table sugar and lactose, which is commonly found in dairy products. Symptoms of carbohydrate malabsorption include watery, explosive diarrhea, bloating, abdominal distension and flatulence. Lactose intolerance is the most common cause of carbohydrate malabsorption. It may also occur in patients who have undergone extensive bowel resection surgery.
  
  
• Protein malabsorption. Inability to digest and absorb proteins (found in foods such as meat, eggs and beans). Symptoms include swelling that may occur anywhere on the body (edema), dry skin and hair loss. This type of malabsorption may be caused by problems with the pancreas.
  
  
• Vitamin malabsorption. Inability to absorb various vitamins from food as it is being digested. This includes water-soluble vitamins (B and C vitamins) as well as fat-soluble vitamins (vitamins A, D, E and K, which can only be digested and absorbed in conjunction with the processing of fats during digestion). Symptoms of vitamin malabsorption depend on the particular vitamin that is not being absorbed. For example, a B-12 deficiency can cause anemia, fatigue, constipation and weight loss. This can occur as a result of celiac disease or Crohn's disease. Vitamin D deficiency can cause a softening of the bones (osteomalacia), vitamin K deficiency can cause easy bruising and vitamin A deficiency may cause vision problems.
  
  
• Mineral malabsorption. Inability to absorb minerals such as calcium, magnesium, iron, zinc and others. Symptoms and causes may vary, according to the deficient mineral. For example, iron deficiency can result in anemia and may be caused by celiac disease.