Cotton is a natural plant fiber that is non-toxic but entirely indigestible for human beings. While a tiny, accidental piece of fiber might pass through the system unnoticed, the deliberate consumption of cotton, such as in the form of cotton balls, can lead to serious gastrointestinal complications. Understanding the chemical structure of the fiber explains why the body cannot process it as food.
The Chemical Composition of Cotton Fiber
The core component of cotton fiber is cellulose, making up approximately 94% to 96% of its total composition in its raw form. Cellulose is a complex carbohydrate, or polysaccharide, that forms the main structural component of plant cell walls. This molecule consists of a long, linear chain of glucose units linked together by specific chemical bonds known as beta-1,4-glycosidic bonds.
The human digestive tract lacks the necessary enzyme, called cellulase, which is required to cleave these particular bonds. Without cellulase, the body cannot hydrolyze the cellulose molecule into its constituent glucose units for absorption and energy. Consequently, cotton fiber passes through the stomach and intestines virtually intact, similar to how dietary fiber from vegetables operates.
Digestive Consequences of Ingestion
Because the fiber is indigestible, it travels through the gastrointestinal tract without being broken down. While the passage of small fragments may not cause immediate problems, consuming larger amounts, such as one or more cotton balls, is medically hazardous. The primary danger stems from the potential for the fiber to accumulate within the digestive system.
The cotton fibers can combine with mucus, partially digested food, and other organic matter to form a dense, immobile mass. This mass is known as a bezoar, specifically a phytobezoar when composed of plant-based material, and it can cause an intestinal obstruction. An obstruction prevents the normal movement of food and liquids through the bowel, leading to severe symptoms like nausea, cramping, abdominal pain, and swelling. If left untreated, an obstruction can lead to tissue death and infection, making surgical removal of the bezoar necessary.
Distinguishing Edible and Non-Edible Cotton Products
The term “cotton” appears in the food industry, but it refers to highly processed or derivative products that are chemically distinct from raw cotton fiber. For instance, food-grade cellulose, sometimes listed as microcrystalline cellulose or powdered cellulose, is a common additive used as a thickener, stabilizer, and anti-caking agent in foods like shredded cheese and ice cream. This purified material is considered safe for consumption and acts as zero-calorie dietary fiber, passing through the body harmlessly.
Cottonseed oil, another cotton-derived product, is a common cooking oil extracted from the seeds of the plant after the fiber is removed. This oil is highly refined, a process necessary to remove a naturally occurring toxin called gossypol, making the oil safe for human consumption. In contrast, the confection known as cotton candy contains no actual cotton fiber. Its structure is simply spun sugar, corn syrup, and coloring that mimics the fluffy appearance of cotton.