The lactose was administered in a glass of water on an empty stomach. A number of those participating in the test, particularly blacks, developed severe gastric upset. The amounts of lactose given, however, were equal to those in 1 to 2 quarts of milk. Later, other researchers questioned the validity of the early studies. They tested subjects who were shown to be lactose intolerant by the original testing methods and found that even these people could consume nutritionally useful amounts of milk without adverse symptoms.
Recent studies continue to support the latter findings.
There apparently is no significant difference in lactose tolerance between black and white children. The new strain of bacteria developed by Dr. Marvin Speck at North Carolina State University, creates a product which tastes like regular milk, although to some it has a sweet aftertaste. The addition of the bacteria is claimed to be beneficial as it helps compensate for bacteria lost in the body through use of antibiotics and food processing. Further research is needed to establish the magnitude of these benefits. Chocolate milk is a nutritious food containing milk nutrients in a concentration equal to that of the unflavored milk from which it is made.