Eating human hair can lead to the accumulation of hair masses known as trichobezoars, which frequently cause blockages and obstructions in the digestive tract. Multiple clinical studies and case reports support this conclusion.
The retrieved papers consistently document that ingested human hair accumulates in the gastrointestinal tract to form trichobezoars, which cause various types of digestive tract obstructions (such as gastric outlet and small bowel obstructions). There is unanimous support in the literature with no papers refuting the claim.