Is A2 milk actually healthier than regular milk?

November 28, 2025 •

3 min read

According to a 2016 study published in the journal Nutrition Journal, participants who drank A2 milk reported significantly less digestive discomfort, bloating, and gas compared to those who consumed conventional A1 milk. But does this mean A2 milk is truly healthier for everyone, or is it only beneficial for those with specific sensitivities?

Quick Summary

This article examines the key differences between A1 and A2 beta-casein proteins and their digestive impacts. We explore the current scientific evidence, including recent human trials, to determine if A2 milk offers proven health advantages over regular milk for certain individuals. Key factors such as cost, availability, and who might benefit most from switching are also discussed.

Key Points

A1 vs. A2 Protein: The key difference lies in the type of beta-casein protein. Regular milk contains a mix of A1 and A2, while A2 milk contains only the A2 protein variant.
Digestive Comfort: For some individuals, the A1 protein in regular milk can trigger digestive discomfort by releasing a peptide called BCM-7 during digestion.
Not a Cure-All: A2 milk is not a substitute for lactose-free milk and is unsafe for those with a cow's milk protein allergy. It still contains lactose and other milk proteins.
Nutritional Parity: Both regular milk and A2 milk have virtually the same nutritional value, providing similar amounts of calcium, protein, and other nutrients.
Consumer Choice: The decision to switch to A2 milk should be based on personal experience. Individuals with A1 protein sensitivity may find relief from digestive issues, while others may not notice any difference.
Limited Research: Broader health claims linking A1 protein to other diseases, like type 1 diabetes or heart disease, are not conclusively proven in humans and require more independent research.

Understanding the difference between A1 and A2 milk

While appearing identical to regular cow's milk, A2 milk differs at the genetic level, specifically concerning the beta-casein protein. Beta-casein is a major protein in milk. Historically, cows produced milk with only the A2 beta-casein protein, similar to human breast milk. However, a genetic mutation resulted in European dairy cows producing the A1 beta-casein variant.

Most modern milk contains a mix of A1 and A2 protein, whereas milk from certain older breeds, like Guernsey and Jersey, is naturally high in A2 protein. Companies producing A2 milk use cows specifically selected for this trait.

The BCM-7 peptide and digestive distress

The primary reason for the perceived health benefits of A2 milk is linked to beta-casomorphin-7 (BCM-7). A1 beta-casein, upon digestion, releases BCM-7, which some research suggests can cause digestive symptoms resembling lactose intolerance in susceptible individuals. The A2 protein's structure prevents the significant release of BCM-7, leading to the idea that A2 milk is easier on the stomach.

Scientific evidence and studies on A2 milk

Recent human trials support the digestive benefits of A2 milk, although research on other health claims is not definitive.

Human Trials on Digestive Health

A 2016 study on Chinese adults with reported milk intolerance found significantly fewer gastrointestinal issues with A2 milk compared to regular A1/A2 milk. The A1 milk group also showed signs of inflammation and slower digestion.
A 2017 review noted that A2 milk may help those with milk intolerance, but highlighted the need for further studies.
A 2024 Korean study on adults experiencing discomfort from milk consumption found reduced abdominal pain and urgency with A2 milk, though it also noted varied individual responses.

Other Health Claims Earlier studies hinted at connections between A1 milk and conditions like type 1 diabetes and heart disease. However, health authorities emphasize that more rigorous research is necessary to confirm these links. A 2017 review suggested insufficient evidence for mechanisms beyond potential digestive benefits.

A2 milk's nutritional profile and side effects

Nutritionally, A2 milk is very similar to regular milk, offering the same levels of essential vitamins, minerals, and fat.

Both milk types support bone health with protein, calcium, and vitamin D.
Crucially, A2 milk still contains lactose and is not suitable for individuals with true lactose intolerance or a milk protein allergy. A milk protein allergy is a serious condition that requires complete avoidance of all dairy protein.

A2 Milk vs. Regular Milk: A Comparison Table


Feature	Regular (A1/A2) Milk	A2-Only Milk	Who Might Benefit	Key Takeaway
Beta-Casein Protein	Mix of A1 and A2.	Only A2.	People with A1 protein sensitivity.	A1 protein linked to BCM-7 peptide.
Digestion	Can produce BCM-7, linked to digestive upset in sensitive people.	Does not produce significant BCM-7.	Individuals with non-lactose related digestive discomfort from dairy.	May be gentler for some, not universally.
Lactose Content	Contains lactose.	Contains lactose.	No benefit for those with true lactose intolerance.	Contains the same milk sugar as regular milk.
Nutritional Value	Provides calcium, protein, potassium, and vitamins.	Similar nutritional profile to regular milk.	All milk drinkers.	Both are nutrient-rich.
Cost & Availability	Generally lower cost, widely available.	Typically more expensive, less available.	Cost-conscious consumers or those without A1 sensitivity.	A2 is a premium product.

How to know if A2 milk is right for you

Determining if A2 milk is suitable often involves personal testing. If you experience mild digestive issues after drinking regular milk, but are not allergic or severely lactose intolerant, A2 milk might offer relief. Try switching to A2 milk for a few weeks to see if symptoms improve. If there is no change, consider lactose-free or plant-based alternatives. Always consult a healthcare professional or registered dietitian for diagnosis and advice before making dietary changes.

Conclusion

For those without milk sensitivities, A2 milk does not offer superior nutritional value compared to regular milk; both are nutritious choices. The primary benefit of A2 milk appears to be for individuals sensitive to the A1 beta-casein protein, who may experience improved digestion. While evidence for this is growing, broader health claims remain unproven and require more independent research. For those with confirmed A1 protein sensitivity, A2 milk provides the nutritional benefits of dairy without the discomfort. The higher cost of A2 milk may not be justified for others. For an authoritative review on the subject, see this Frontiers in Nutrition article.

Frequently Asked Questions

The primary difference is the type of beta-casein protein they contain. Regular milk from most Western dairy cows contains a mix of A1 and A2 beta-casein, while A2 milk comes from specially selected cows that only produce the A2 protein variant.

No, A2 milk is not lactose-free. It contains the same amount of lactose as regular cow's milk and should be avoided by individuals with a diagnosed lactose intolerance, though some with milk sensitivity report improved digestion.

No, A2 milk is not safe for people with a true cow's milk protein allergy. It still contains casein and other proteins that can cause an allergic reaction.

Scientific studies, including some human trials, suggest that A2 milk may be easier to digest for certain people who are sensitive to the A1 beta-casein protein. However, evidence for other health claims, such as links to chronic disease, is not conclusive.

Unlike the A1 protein, which releases the potentially inflammatory peptide BCM-7 during digestion, the A2 protein does not. This can lead to fewer digestive issues like bloating, gas, and discomfort in sensitive individuals.

Yes, from a general nutritional standpoint, A2 milk is very similar to regular milk. Both are rich in essential nutrients like protein, calcium, potassium, and vitamin D.

People who experience digestive discomfort, such as bloating and gas, after consuming regular milk but who do not have a diagnosed cow's milk allergy or severe lactose intolerance may find A2 milk to be a gentler alternative.

The most effective way is a process of elimination under the guidance of a healthcare professional. You can try switching to A2 milk for a period of time and observe if your digestive symptoms improve.