What Does A2 Mean on Dairy Products? A Nutritional Guide

October 10, 2025 •

3 min read

Did you know that not all milk is the same, and the difference comes down to the type of protein it contains? For those wondering, what does A2 mean on dairy products?, it refers to milk that contains only the A2 type of beta-casein protein, which some people may find easier on their digestion than the A1 protein found in most conventional milk.

Quick Summary

A2 dairy products contain only the A2 beta-casein protein, contrasting with regular milk that has both A1 and A2 proteins. This may result in better digestive comfort for sensitive individuals, although it is not a solution for lactose intolerance or milk protein allergies.

Key Points

A2 Protein vs. A1 Protein: A2 dairy products contain only the A2 beta-casein protein, unlike conventional milk which typically contains both A1 and A2 proteins.
Easier Digestion for Some: For people sensitive to the A1 protein, A2 milk can be easier to digest and may alleviate symptoms like bloating and gas.
No Solution for Lactose Intolerance: A2 milk still contains lactose, so it is not a suitable substitute for those with a medically diagnosed lactose intolerance or milk protein allergy.
Genetic Origins: The A2 protein is considered the original type of beta-casein in cows' milk, while the A1 protein is the result of a genetic mutation that occurred over centuries.
BCM-7 Peptide: The digestive difference is attributed to the A1 protein's release of the BCM-7 peptide, which does not happen with the A2 protein and is linked to digestive discomfort.
Source Breeds: Indigenous and ancient cow breeds like Gir and Jersey are more likely to produce A2 milk naturally, while common breeds like Holstein often produce a mix.
Similar Nutrition: Other than the protein type, A2 milk offers the same vitamins, minerals, and nutritional value as regular milk.

The Science Behind A2: Understanding Beta-Casein

Understanding what "A2" means requires knowing about the two primary types of beta-casein protein in cow's milk: A1 and A2. While these proteins are very similar, with a minor difference in their amino acid structure, this variance impacts how the body processes them. Initially, A2 was the predominant type in milk, but a natural genetic change in some European cows introduced the A1 protein. Consequently, most modern milk from breeds like Holsteins contains both A1 and A2 proteins, while A2 dairy products come from specially selected cows that produce milk with only the A2 protein.

The Digestive Difference: A1 vs. A2 Protein

The main difference lies in how A1 and A2 proteins are broken down during digestion. A1 protein can release beta-casomorphin-7 (BCM-7), a peptide linked to digestive discomforts like bloating, gas, and stomach pain in some individuals. In contrast, the A2 protein does not release significant amounts of BCM-7. Switching to A2 milk may alleviate these symptoms for those sensitive to the A1 protein, but it's important to remember this is distinct from lactose intolerance, as A2 milk still contains lactose.

Potential Benefits of A2 Dairy

For individuals sensitive to A1 protein, A2 dairy may offer digestive benefits:

Improved Digestive Comfort: The absence of significant BCM-7 release can make A2 milk easier to tolerate for some.
Reduced Inflammation: Avoiding BCM-7, which some research links to gut inflammation, may support better gut health.
Relief for Self-Reported Intolerance: Studies have shown reduced gastrointestinal symptoms in individuals consuming only A2 milk compared to conventional milk.

A Comparison of A1 and A2 Milk


Feature	Conventional Milk (A1 & A2)	A2 Milk (A2 Only)
Beta-Casein Protein	Contains a mixture of both A1 and A2 proteins, which is common in modern dairy breeds.	Contains only the A2 beta-casein protein, sourced from genetically selected cows.
Digestive Byproduct	Upon digestion, the A1 protein can release the peptide Beta-Casomorphin-7 (BCM-7).	The A2 protein does not release BCM-7 upon digestion, making it potentially gentler on the stomach.
Potential Digestive Impact	Can cause symptoms like bloating, gas, and general discomfort for some sensitive individuals.	May reduce or eliminate digestive discomfort for those sensitive to A1 protein.
Nutritional Profile	Contains the same essential vitamins, minerals, and calories as A2 milk.	Offers the same essential nutrients, such as calcium, protein, potassium, and vitamins A & D, as conventional milk.
Source Breeds	Most common dairy breeds, like Holstein, contain a mix of A1 and A2 genetics.	Certain ancient or indigenous breeds like Gir, Sahiwal, and Jersey are naturally more likely to produce A2 milk.

How A2 Dairy Products Are Produced

A2 dairy production is a meticulous process focused on genetics and segregation. It involves genetically testing cows to identify those with the A2/A2 beta-casein makeup, segregating these cows into dedicated A2 herds, and processing their milk separately to prevent A1 contamination. The milk is tested again to confirm only A2 protein is present before being packaged and labeled as A2.

A2 Milk: Is It for You?

A2 milk can benefit those sensitive to A1 protein, but it is not a solution for everyone with dairy issues. Individuals with a true cow's milk protein allergy will react to both A1 and A2 milk. Similarly, A2 milk won't help with lactose intolerance, as it contains lactose. However, some with self-diagnosed lactose intolerance may find relief, suggesting A1 sensitivity was the real issue.

Always consult a healthcare professional or registered dietitian before changing your diet to identify the source of digestive issues and determine if A2 milk is appropriate. Further information can be found on the a2 Milk Company's website.

Conclusion: The Bottom Line on A2 Dairy

In summary, what does A2 mean on dairy products? It signifies milk containing only the A2 beta-casein protein. For some, the absence of the A1 protein and its associated peptide (BCM-7) leads to better digestive comfort. A2 milk provides the same nutritional value as regular milk but with a protein structure that may be gentler on sensitive stomachs. While not a treatment for allergies or lactose intolerance, it's a valuable option for those affected by A1 protein sensitivity, offering a way to enjoy dairy through careful selection and processing.

Frequently Asked Questions

Yes, A2 milk contains the same amount of lactose as regular cow's milk. It is not lactose-free and will not resolve symptoms related to lactose intolerance.

If you experience digestive discomfort like bloating, gas, or stomach ache after consuming regular milk, but have tested negative for lactose intolerance or milk protein allergy, you may have A1 protein sensitivity. Trialling A2 milk can help determine if this is the cause.

From a basic nutritional standpoint, A2 milk is not inherently 'better' as it contains the same key nutrients as regular milk. However, for those with A1 protein sensitivity, it is the better choice for avoiding digestive issues.

A2 milk differs by the type of beta-casein protein it contains, while lactose-free milk has the lactose (milk sugar) removed or treated. You can find lactose-free A2 milk for those who are both lactose intolerant and sensitive to the A1 protein.

Certain ancient and indigenous breeds naturally produce A2 milk, including Gir, Sahiwal, and Jersey cows. Modern breeds like Holsteins typically produce a mix of A1 and A2 milk proteins.

No. A2 milk is not safe for infants or individuals with a medically diagnosed cow's milk protein allergy (CMPA) because it still contains milk proteins that can trigger an allergic reaction. Please consult a pediatrician for appropriate alternatives.

Dairy companies ensure their A2 products are free of the A1 protein through genetic testing of their cow herds and meticulous segregation of milk production. Lab tests are also used to verify the A2 status before bottling.