Some data suggest that sorbitol intake may be responsible for diarrhea in diabetic patients. One hundred thirteen hydrogen breath tests were performed in type II diabetics (72) and normal controls (41) after oral loads of sorbitol ranging from 2.5 to 20 g in iso-osmolar solutions to assess the role of malabsorption of this compound in the genesis of abdominal symptoms. The prevalence of sorbitol malabsorption and abdominal symptoms, peak (Cmax H2) and total (Ctot H2) hydrogen production, and mouth to cecum transit time (MCTT) did not differ in type II diabetics and controls. Malabsorption was observed more frequently with the highest doses of sorbitol (10% of patients at a dose of 2.5 g and approximately 75% at 20 g). Symptoms, usually consisting of mild discomfort and abdominal distension, were observed only after sorbitol loads of 10 and 20 g in 27.2% of the diabetics and in 36.3% of the controls. Diarrhea was present in three subjects (two diabetics and one control) only at a dose of 20 g. These data indicate that it is highly unlikely for sorbitol to play a role in inducing diabetes diarrhea. A moderate (up to 10 g) sorbitol intake is not contraindicated in type II diabetics.