Once upon a time, milk options were limited to whole, low-fat, skim, and, if you were lucky, chocolate. Today, the dairy aisle is brimming with choices—walnut milk, flax milk, oat milk, goat milk, and even the lesser-known A2 milk.
What is A2 Milk?
A2 milk is cow’s milk that primarily contains A2 beta-casein, a protein believed to be easier for the body to digest and absorb. Unlike most cow’s milk in the U.S., which contains a mix of A1 and A2 beta-casein, A2 milk is unique in its composition.
First introduced in 2003 by New Zealand’s A2 Milk Company, this product has grown into a $2 billion industry. Today, A2 milk is available at over 29,000 retailers across the U.S., including major stores like Costco and Walmart. It comes in whole, reduced-fat, and skim varieties, just like traditional milk.
A1 Milk vs. A2 Milk
A2 milk producers claim that A1 beta-casein can be harder for some people to digest and may affect healthy blood sugar levels. However, research supporting these claims remains limited. Casein, the primary protein group in milk, makes up 82% of milk’s protein content, with the remaining 18% being whey protein. There are 13 types of casein, with A1 and A2 being the most common.
How is A2 Milk Made and What Makes It Different?
A2 milk comes from cows with a genetic variant that produces milk containing only A2 beta-casein, lacking the A1 variant. These cows are primarily found in Asia, Africa, and parts of Southern Europe, whereas cows in the Western world typically produce milk with both A1 and A2 beta-casein.
Potential Benefits of A2 Milk
Does A2 milk offer any advantages over regular milk? According to Dana Hunnes, Ph.D., RD, MPH, senior dietitian at Ronald Reagan UCLA Medical Center, “It’s hard to answer this question because most A2 milk studies have been funded by the A2 Milk Company and the dairy industry, which may bias the results.” Here are some of the claims made about A2 milk:
1. Easier Digestion
Studies funded by the A2 Milk Company suggest that A1 beta-casein can take longer to digest in some people, potentially causing digestive discomfort, bloating, and gas. A 2019 review suggested this could be true, but noted that more human studies are needed. Additionally, a study at Purdue University found that lactose-intolerant participants experienced fewer gastrointestinal symptoms after consuming A2 milk compared to regular cow’s milk.
2. Supports Healthy Blood Sugar Levels
The California Milk Research Foundation notes that some scientists have theorized that A1 beta-casein could negatively impact blood sugar levels and cardiovascular health. This theory centers around BCM-7, an amino acid peptide produced during the digestion of A1 beta-casein, which may cause issues in individuals with immune deficiencies. However, there is no scientific evidence to support this claim in humans.
Potential Risks of A2 Milk
The risks associated with A2 milk are similar to those of regular cow’s milk.
Lactose Intolerance
A2 milk contains the same amount of lactose as regular cow’s milk, meaning individuals with lactose intolerance may still experience digestive discomfort.
Allergies
Since A2 milk is still cow’s milk, it can trigger allergic reactions in those with a cow’s milk allergy.
