Which is better A1 curd or A2 curd?

November 3, 2025 •

3 min read

According to scientific research, a key difference in protein structure can impact how some people digest dairy. This distinction is central to the debate over which is better A1 curd or A2 curd for digestive comfort, especially for those with dairy sensitivities.

Quick Summary

This article explores the core differences between A1 and A2 curd, focusing on how their protein variations can affect digestion and overall gut health. It examines the controversial peptide BCM-7, potential benefits of A2 dairy, and helps consumers make an informed choice based on their individual tolerance.

Key Points

Protein Difference: The main distinction between A1 and A2 curd is a single amino acid variation in the beta-casein protein.
BCM-7 Peptide: The A1 protein, but not the A2 protein, can release the peptide BCM-7 during digestion, which is linked to potential digestive discomfort.
Easier Digestion: For some individuals, A2 curd can lead to less bloating and digestive distress, offering a gentler alternative to conventional curd.
Not for Lactose Intolerance: The A1/A2 distinction is about protein, not lactose. True lactose intolerance is a different issue, though curd's fermentation reduces lactose.
Individual Response is Key: How A1 and A2 curd affect you is individual. The best approach is a self-trial to compare your digestive comfort after consuming each type.
Indigenous vs. European Cows: A2 milk comes from indigenous breeds like Gir and Sahiwal, while A1 milk is common in European breeds like Holstein.

Understanding the Core Difference: A1 vs. A2 Protein

At the heart of the A1 versus A2 curd debate is the type of beta-casein protein present in the milk used to make it. Milk from many commercially farmed European cow breeds contains A1 beta-casein, while A2 beta-casein is found in the milk of indigenous Indian cow breeds, goats, sheep, and water buffalo. A single amino acid difference at position 67 distinguishes A1 (histidine) from A2 (proline).

The Impact of BCM-7 Peptide

This structural difference affects digestion. A1 beta-casein can release beta-casomorphin-7 (BCM-7) upon breakdown in the gut. BCM-7 has been controversially linked to digestive issues like bloating and slower transit time in some individuals. The proline in A2 beta-casein prevents significant BCM-7 release during digestion.

The Health Benefits of A2 Curd

For those with dairy sensitivities, A2 curd is often seen as a milder option due to minimal BCM-7 release, potentially leading to less bloating and discomfort.

Easier Digestion: Less BCM-7 release may support more comfortable digestion.
Reduced Inflammation: Some studies suggest A1 is linked to inflammatory markers in sensitive individuals, an effect not typically seen with A2.
Improved Gut Health: A2 milk consumption has been associated with beneficial gut bacteria.
Better Nutrient Absorption: Easier digestion could improve the absorption of curd's nutrients.

A1 Curd: The Potential Downsides

Potential issues with A1 curd are mainly tied to the digestion of the A1 protein and BCM-7 release.

Digestive Discomfort: Symptoms like bloating, gas, and pain have been reported by some.
Possible Inflammatory Response: BCM-7 might trigger gut inflammation in sensitive people.
Slower Gut Transit: Animal studies show BCM-7 can slow digestion.
Nutrient Malabsorption: Inflammation and slowed digestion may hinder nutrient absorption.

Comparison Table: A1 Curd vs. A2 Curd


Feature	A1 Curd (Conventional)	A2 Curd (Specialty)
Beta-Casein Protein	Contains A1 protein, often with a mix of A2	Contains exclusively A2 protein
BCM-7 Release	Releases the opioid peptide BCM-7 upon digestion	Minimally or does not release BCM-7
Potential Digestion Issues	Linked to bloating, gas, and digestive discomfort for some	Often associated with easier and more comfortable digestion
Inflammation Risk	Linked to increased inflammatory markers in sensitive individuals	Associated with lower inflammatory markers
Cow Breeds	Primarily from European breeds like Holstein and Friesian	From indigenous breeds like Gir, Sahiwal, and certain Jersey cows
Availability	Widely available in commercial markets	Available in specialty stores or from specific A2 dairy producers
Price	Generally lower cost due to widespread production	Often higher cost due to specialized farming and testing

Making an Informed Decision

For most people without dairy issues, A1 and A2 curd are nutritionally similar. However, those experiencing discomfort may find A2 curd helps, symptoms sometimes mistaken for lactose intolerance. It's crucial to note that A1/A2 is about protein, not lactose. Curd's fermentation reduces lactose, but A2 dairy isn't a solution for true lactose intolerance.

A personal trial is the best way to see which works for you. Replace your usual curd with A2 for a few weeks and track symptoms. Products are usually clearly labeled.

Conclusion: The Final Verdict

While offering similar nutrition, A2 curd is often preferred by those with digestive discomfort potentially linked to A1 protein and BCM-7 release. For the majority without sensitivities, both are nutritious. The best choice is personal and depends on your body's response. Consulting a healthcare provider can also be beneficial. A balanced view considering both research and individual experience guides an informed choice. For further details on the A1 vs. A2 dairy debate, refer to the review published in MDPI.

Frequently Asked Questions

A2 curd may be tolerated better by some individuals who experience symptoms from A1 protein, but it is not lactose-free. The fermentation process naturally reduces the lactose content, which can help, but it won't resolve true lactose intolerance.

BCM-7 (beta-casomorphin-7) is a peptide released during the digestion of A1 protein. In some people, it can cause digestive discomfort and has been linked to inflammatory responses in the gut, potentially affecting motility and microbial balance.

A2 curd is typically made from the milk of indigenous cow breeds like Gir or Sahiwal. Products specifically made from A2 milk will often be labeled as such. Conventional curd is usually made from milk containing a mix of A1 and A2 proteins.

The taste difference is minimal for most people. A2 curd, especially from indigenous cow breeds, is often described as richer and creamier due to a higher fat content, but the difference is subtle and not related to the A1/A2 protein variants themselves.

The scientific community remains divided, with some studies highlighting potential negative effects of A1 protein digestion in sensitive individuals, while others find no conclusive evidence. Most research indicates that the effects are highly individual and dependent on genetic susceptibility.

For some people, bloating and other digestive discomforts are a reaction to the BCM-7 peptide from A1 protein, not lactose. In these cases, switching to A2 curd, which does not release BCM-7, can significantly reduce bloating and other symptoms.

Historically, all cows produced A2 milk. A genetic mutation led to the emergence of the A1 variant. Today, A2 milk is primarily produced by indigenous Indian breeds (Gir, Sahiwal), Jersey cows, and other heritage breeds.