Stools that float are generally associated with some degree of malabsorption of nutrients or excessive flatus (gas).

Floating stools are seen in a variety of different situations. Most are diet-related, or caused by episodes of diarrhea  that accompany an acute gastrointestinal infection. A change in dietary habits can lead to an increase in the amount of gas produced by bacteria in the gastrointestinal tract.

Similarly, acute gastrointestinal (GI) infections can result in increased gas content in the intestines, due to rapid movement of food through the GI tract. One wrong idea is that floating stools are caused by an increase in the fat content of the stool. In fact, it is increased gas levels in the stool that make it less dense and allow it to float.

Another cause of floating stools is malabsorption. More than two weeks of diarrhea with floating stools is often seen in people suffering from malabsorption, a dysfunction in the GI tract that affects the body's ability to digest and absorb fat and other types of foods.

Increased levels of nutrients in the stool (which have not been absorbed by the GI tract) are supplied to the normal bacteria that live in the gut, which in turn produce more gas. This results in more gas-rich stools that float.

Dietary changes, diarrhea, and malabsorption can cause floating stools. Most causes are benign and will resolve when the infection ends or the bacteria in the GI tract adjust to the changes in your diet.

Patients with the following diseases may also have stool that floats:

• Cystic fibrosis
• Gluten-induced enteropathy (sprue or celiac disease)
• Idiopathic steatorrhea (fatty stools with no known cause)
• Disaccharides deficiency (insufficient amounts of the sugar-digesting enzymes lactase, sucrase, or isomaltase)
• Short bowel syndrome
• Biliary atresia
• Abetalipoproteinemia

Floating stools alone do not indicate an illness or problem, and they do not require home care. If a change in diet has caused problems, try to find and eliminate the offending food.