Could drinking a2 Milk™ help lactose intolerant people digest dairy long-term?

The study participants will consume conventional cheese and milk for two weeks and a2 Milk™ cheese and milk for two weeks (with a recovery break between), to see if benefits of a2 Milk™ identified in an earlier study by the same researchers persist over a longer period.

That 2017 study, a collaboration between the Liggins Institute and AgResearch, found that a2 Milk™ prevents some symptoms of lactose intolerance and eases others, even though it contains the same amount of lactose as conventional milk.

Researchers showed a2 Milk™ was at least as effective as lactose-free milk at preventing or reducing some symptoms including nausea, stomach pain and bloating, but didn’t improve ratings of “overall digestive comfort”. It also produced the same levels of flatulence and gastric reflux as regular milk.

Globally, about 70 percent of adults consider themselves lactose intolerant, and experience bloating, nausea or other unpleasant symptoms after consuming dairy products.

Study lead Dr Amber Milan, a research fellow at the Liggins Institute says: “We already know that lactose intolerant people can sometimes build up their tolerance to lactose over time by including lactose or milk in their diet. If we can help that process along, hopefully we can improve digestion of lactose after just a few weeks. We’re hopeful that consuming dairy with only the A2 protein will reduce symptoms by avoiding inflammation that might make intolerance worse.”

Regular milk contains both the A1 and A2 types of beta-casein protein, a major milk protein, while a2 Milk™ comes from cows that naturally produce only the A2 type.

Explains AgResearch scientist Matthew Barnett: “There is evidence from animal studies that a breakdown product of the A1 protein causes inflammation in the small intestine, which could make lactose intolerance symptoms worse.”

The new study, dubbed Los aMiGoS, has been designed to minimise uncomfortable symptoms by limiting daily lactose to the equivalent of two glasses of milk - an amount that is usually tolerable for people with lactose intolerance. To spare participants unnecessary discomfort, researchers will top up their protein consumption with daily servings of cheese, which is nearly lactose-free. Cheese from a2 Milk™ has been especially created for the study. Neither the participants nor researchers will know which kind of dairy they’re consuming for each fortnight stretch.

Participants need to be aged 20-40, believe they are lactose intolerant, and be willing to give this study a go. People interested in joining the a2 Milk™ for Gut Comfort Study can email nutrition.mobility@auckland.ac.nz or call 09 923 1151 or 022 1837 265.

This study is funded through High Value Nutrition to AgResearch and in partnership with the a2 Milk™ Company.

Key Points

• Last year, researchers from the Liggins Institute and AgResearch showed that after just one large serve, a2 Milk™ prevents some symptoms of lactose intolerance and eases others, even though it contains the same amount of lactose as conventional milk. It’s thought that a protein in conventional, but not a2 Milk™, causes inflammation in the gut which makes lactose intolerance symptoms worse.
• Now, the researchers are looking at what happens when people with lactose intolerance drink a2 Milk™ every day for two weeks. Study participants could come out better able to tolerate dairy long-term.
• People interested in joining the study can read the Los aMiGoS page.
• Check out the video clip about 2017 a2 Milk™ and lactose intolerance study findings