Results of a human clinical trial show that A1 protein in cow's milk may trigger symptoms of lactose intolerance.

 According to new clinical research released today, lactose intolerance may be a myth for many, with resulting symptoms from drinking milk most likely an inflammatory response to the A1 protein found in conventional cow's milk.

Published in the prestigious U.K. based Nutrition Journal, the study led by Professor Sun Jianqin from Huadong Hospital, an affiliate of the renowned Fudan University in Shanghai, China compared the impact of humans drinking conventional cow's milk – milk with the A1-protein – to that of milk that is A1-protein free.

• China chosen for clinical research due to the high prevalence of lactose intolerance in the country (nearly 90%1 of population reports lactose intolerance).
• First human study-based research testing the effects of the A1 versus A2 protein types2 on participants with clinically diagnosed lactase deficiency/lactose intolerance3.
• Conventional cow's milk (containing A1 protein type) caused significantly higher gastrointestinal inflammation, stool transit delays, and elevated blood markers for inflammation and immune response compared to milk containing only the A2 protein (free-from the A1 protein type).

The study was supported by The a2 Milk® Company, an Australian milk company specializing in milk from cows selected because they naturally produce only milk containing the A2 protein type. After overwhelming success in Australia and more recently growing popularity in China, a2 Milk® launched in the United States, with major plans for nationwide distribution. The a2 Milk Company entered select U.S. markets, first in California, and is available in all major grocers, including Whole Foods, Sprouts and Fresh Market nationally.

"This research confirms the post-dairy digestive discomfort may not always be the result of lactose intolerance," said Jeff O'Neill, president, The a2 Milk Company, U.S. "Lactose is what usually takes the blame for millions of people worldwide with digestive issues associated with ordinary cow's milk, leading many to give up milk altogether. The evidence is strong that an inflammatory response to the A1 protein may be the issue for a large proportion of people."

Originally, all cows only produced milk containing the A2 type of beta-casein protein. However, after domestication, another milk protein type – A1 protein type – appeared in European herds and spread along with human migration. A1 protein is contained in the vast majority of cow's milk consumed in the U.S. today.

A 2009 study published in Nutrition Today, found approximately 1-in-4 Americans (significantly higher proportions within Asian, African American and Hispanic populations) experience digestive issues when consuming conventional cow's milk, with the majority incorrectly associating these symptoms to lactose intolerance. The new China based research further supports these findings.

This Chinese research is the first human-based research testing the effects of the A1 versus A2 protein types on participants, half who were clinically confirmed as truly having issues with lactose digestion. The trial found milk containing only the A2 protein type caused no gastrointestinal disturbance in any study participants, including those confirmed to have issues digesting lactose.

Study participants who drank conventional cow's milk (containing the A1 protein), experienced elevated gastro-intestinal inflammation, stool transit delays, and elevated markers for inflammation and immune response. When participants drank milk containing only the A2 protein, it was significantly gentler on their digestive system, with less inflammation associated with bloating and abdominal pain.

According to contributing author, Associate Professor Xia, Gastroenterologist at the Shanghai Jiaotong University School of Medicine, and Adjunct Associate Professor at Johns Hopkins University School of Medicine, "These are significant findings for those who believe they suffer from lactose intolerance. The research suggests milk that only contains the A2 type protein (A2 beta-casein) has a natural affinity with the human body and digestion. Gut inflammation caused by the A1 type protein can be avoided by consuming milk products with only the A2 type protein. With so many people believing they are lactose intolerant, both inChina and around the world, the findings are truly noteworthy." 

About the trial

The trial recruited 45 healthy participants in Shanghai, China, with a history of self-reported milk intolerance into a double-blinded, randomized, 8-week crossover study. For the initial two weeks, participants abstained from all dairy products. The following two weeks, participants only drank conventional cow's milk (A1 protein-containing), followed by another two weeks of abstaining from dairy products. This was followed by two weeks of drinking only a2 Milk®. Twenty-three of the 45 were clinically diagnosed as lactase deficient and remaining subjects claimed they had a digestive sensitivity to dairy. Both researchers and participants were blinded to the milk they were drinking at all phases of the trial.

What is the a2 Milk® difference?

• The a2 Milk® brand is a naturally occurring milk from cows selected to naturally produce only the A2 beta-casein protein type, without the A1 protein. a2 Milk® is 100% pure cow's milk with absolutely no technological process or genetic engineering.
• Since the beginning of time, all domesticated cows produced only the A2 type protein. Because of a naturally occurring genetic mutation in European herds, another milk protein appeared (A1 protein), and spread worldwide because of human migration and modern farming practices. Overwhelmingly, most milk consumed today contains the A1 protein.
• The a2 Milk® brand is the only cow's milk in the United States naturally free from the A1 protein.

About The a2 Milk Company

The a2 Milk Company is a group of exceptional and premium dairy products naturally free from the A1 protein, supported by an integrated portfolio of intellectual properties, and a comprehensive body of scientific evidence. The a2 Milk Company believes all humans should enjoy the benefits of fresh and natural dairy products, and are and are pioneering a natural alternative for those who have a sensitivity to conventional cows' milk.

Founded in New Zealand, The a2 Milk Company is a significant success in Australia, with a nearly 10% market share of the total fresh milk grocery market, and more recently established operations in China and the U.K. The a2 Milk Company recently launched in the United States, first in California, and now expanding country-wide. For more information go to www.a2milk.com and like us on Facebook.

1  Source: New Scientist, "Everything you need to know about lactose intolerance", July 2015
2  A1 and A2 protein refers to A1 and A2 beta casein protein types 
3  23 of 45 study participants demonstrated lactase deficiency by urinary galactose (U-Gal) test with corresponding symptoms of lactose intolerance measured

SOURCE The a2 Milk Company

RELATED LINKS
http://www.a2milk.com

BOULDER, Colo., April 20, 2016 /PRNewswire/ --