Long-term acceptance of low-lactose milk.

Low-lactose milk was produced by incubating cow's milk with yeast lactase. Sixteen lactose tolerant and 15 intolerant volunteers ingested 500 ml of the product twice daily for 1 month. During the testing period all subjects received on three occasions the same volume of unmodified milk in double-blind tests. Symptoms recorded throughout the study and for an additional 15 day base-line observation period were: diarrhea, abdominal pain and distention, flatulence, heartburn, and headache. Low-lactose milk acceptance was excellent. No significant differences were found between tolerants and intolerants during the base-line period and while ingesting low-lactose milk. By contrast, unmodified milk induced severe symptoms only in the intolerants. Availability of low-lactose milk and of its by-products allows consumption of greater volumes of this highly nutritious food by subjects with lactose intolerance with none or less symptoms compared to unmodified milk.