Send to

Choose Destination
J Pediatr Gastroenterol Nutr. 2019 Sep;69(3):375-382. doi: 10.1097/MPG.0000000000002437.

Effects of Conventional Milk Versus Milk Containing Only A2 β-Casein on Digestion in Chinese Children: A Randomized Study.

Author information

Department of Children and Adolescents Health Care, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, MOE-Shanghai Key Lab for Children's Environmental Health, Shanghai.
Department of Pediatric Gastroenterology, Peking University Third Hospital, Beijing.
S.P.R.I.M. China (Shanghai) Consulting Co., Ltd., Shanghai, China.
School of Health Sciences, RMIT University, Bundoora.
Department of Gastroenterology, Central Clinical School, Monash University, Victoria, Australia.



In this study, we hypothesized that replacing conventional milk, which contains A1 and A2 β-casein proteins, with milk that contains only A2 β-casein in the diet of dairy or milk-intolerant preschoolers (age 5 to 6 years) would result in reduced gastrointestinal symptoms associated with milk intolerance, and that this would correspond with cognitive improvements.


This randomized, double-blind, crossover study aimed to compare the effects of 5 days' consumption of conventional milk versus milk containing only A2 β-casein on gastrointestinal symptoms, as assessed via visual analog scales, average stool frequency and consistency, and serum inflammatory and immune biomarkers in healthy preschoolers with mild-to-moderate milk intolerance. The study also aimed to compare changes in the cognitive behavior of preschoolers, based on Subtle Cognitive Impairment Test scores.


Subjects who consumed milk containing only A2 β-casein had significantly less severe gastrointestinal symptoms as measured by visual analog scales, reduced stool frequency, and improvements in stool consistency, compared with subjects consuming conventional milk. There were significant increases from baseline in serum interleukin-4, immunoglobulins G, E, and G1, and beta-casomorphin-7 coupled to lower glutathione levels, in subjects consuming conventional milk compared with milk containing only A2 β-casein. Subtle Cognitive Impairment Test analysis showed significant improvements in test accuracy after consumption of milk containing only A2 β-casein. There were no severe adverse events related to consumption of either milk product.


Replacing conventional milk with milk containing only A2 β-casein reduced gastrointestinal symptoms associated with milk intolerance in Chinese preschool children, with corresponding improvements in aspects of cognitive performance.

Supplemental Content

Full text links

Icon for Wolters Kluwer
Loading ...
Support Center