Foods that Contain A1 Beta-Casein Protein

Approximately 20% of adults experience abdominal discomfort after consuming dairy, which is often mistakenly attributed solely to lactose intolerance. However, a growing body of research suggests that the A1 beta-casein protein found in the milk of certain cow breeds could be a contributing factor. This article explores what foods contain A1 beta-casein and how you can make informed choices about your dairy consumption.

Quick Summary

This guide details the specific dairy products and cow breeds most likely to contain A1 beta-casein, a protein variant linked to digestive issues in some people. It provides a breakdown of common A1-containing foods and compares them with A2 and other alternatives.

Key Points

• Source of A1 Beta-Casein: A1 beta-casein is a protein found predominantly in milk from cow breeds of Northern European origin, such as Holstein, Friesian, and Ayrshire.

• Digestive Issues: For some individuals, the digestion of A1 beta-casein can release a peptide called BCM-7, which is linked to gastrointestinal discomfort and inflammation.

• Affected Dairy Products: Standard milk, cheese, yogurt, and other products made from conventional cow's milk contain a mixture of A1 and A2 beta-casein.

• A2-Only Alternatives: Milk and dairy products specifically labeled as 'A2 milk' come from genetically tested cows that produce only the A2 beta-casein protein.

• Other Milk Options: Goat, sheep, and buffalo milk naturally contain A2-like beta-casein, offering a natural alternative to A1 cow's milk.

• Not Lactose Intolerance: Sensitivity to A1 beta-casein is different from lactose intolerance, and symptoms can persist even with lactose-free A1 milk.

What is A1 Beta-Casein?

Beta-casein is a protein that makes up a significant portion of the protein content in cow's milk. There are two primary variants: A1 and A2. A1 beta-casein is a result of a genetic mutation that occurred in European dairy cows several thousand years ago. The key difference lies in a single amino acid at position 67 of the protein chain, which affects how it is digested. When broken down, A1 beta-casein releases a peptide called beta-casomorphin-7 (BCM-7), which has been linked to digestive issues, inflammation, and discomfort in sensitive individuals.

The Difference Between A1 and A2 Digestion

The difference between the digestion of A1 and A2 beta-casein is subtle but significant for some people. During the digestion of A1 milk, the histidine amino acid at position 67 allows for the release of the opioid peptide BCM-7. In contrast, the proline amino acid at the same position in A2 beta-casein prevents the cleavage and release of BCM-7, leading to a different and often less inflammatory digestive process. This distinction is why some people who experience discomfort with standard cow's milk find that they can tolerate A2 milk without issue, even if they are not lactose intolerant.

Common Dairy Foods Containing A1 Beta-Casein

Because the A1 gene is prevalent in dairy herds of Northern European origin, most conventional dairy products sold in supermarkets contain a mixture of both A1 and A2 beta-casein. The concentration of A1 protein can vary depending on the cow breed and the overall herd genetics.

Here is a list of common dairy products that are likely to contain A1 beta-casein:

• Standard Cow's Milk: Unless specifically labeled as A2 milk, all conventional milk from breeds like Holstein and Friesian contains a mixture of A1 and A2 proteins. This includes full-fat, low-fat, and skim varieties.
• Cheese: Most cheeses are made from conventional cow's milk. Hard cheeses like cheddar and parmesan, as well as soft cheeses such as mozzarella and cream cheese, likely contain A1 beta-casein.
• Yogurt: The majority of yogurts, including Greek yogurt and flavored varieties, are produced from standard cow's milk and will therefore contain A1 protein.
• Ice Cream: Ice cream and gelato are classic dairy products that are almost always made from a blend of A1 and A2 milk, unless a specific A2 version is purchased.
• Butter and Cream: While primarily fat, these products are derived from cow's milk and can contain trace amounts of casein protein, including A1.
• Milk Powder and Whey Protein: These concentrated dairy ingredients are used in many processed foods, from baked goods to protein supplements, and typically contain A1 beta-casein.

Cow Breeds That Produce A1 Milk

Understanding the source of your dairy can help in avoiding A1 beta-casein. Certain breeds of cows are known to produce milk higher in A1 protein, while others primarily produce A2 protein.

• High A1 Producers: Holstein, Friesian, Ayrshire, and British Shorthorn cows typically produce milk with a high concentration of A1 beta-casein. These breeds are extremely common in Western commercial dairy farming.
• High A2 Producers: The original beta-casein variant was A2, and some breeds still produce milk predominantly containing this protein. These include indigenous Indian breeds like Gir, Sahiwal, and Red Sindhi, as well as some Channel Island breeds like Guernsey and Jersey.

Alternatives to A1 Beta-Casein Foods

For those who experience digestive issues with conventional dairy, several alternatives are available. Some people find relief by switching to dairy products with a different protein profile, while others prefer to avoid cow's milk entirely.

A2-Only Dairy Products

An increasing number of dairy companies offer products made exclusively from the milk of cows that produce only the A2 beta-casein protein. This involves genetic testing of herds to ensure the absence of the A1 gene. A2 milk products include liquid milk, yogurt, and other dairy items.

Other Animal Milk

Milk from other mammals naturally contains the A2-like beta-casein protein, offering another option for those sensitive to A1. Goat, sheep, and buffalo milk are often more easily digested by those who have difficulty with standard cow's milk.

Non-Dairy Alternatives

For a complete avoidance of dairy protein, plant-based milk alternatives are widely available. These include milks made from almonds, oats, soy, and coconuts. When choosing soy milk, it is important to check the label to ensure no casein has been added.

Comparison of A1 Dairy vs. Alternatives

Feature	Conventional A1/A2 Cow's Milk	A2-Only Cow's Milk	Goat/Sheep Milk	Plant-Based Milk Alternatives
Beta-Casein Type	A mixture of A1 and A2.	Only A2.	Only A2-like.	No beta-casein.
Digestion	May cause digestive discomfort due to BCM-7 release in some individuals.	Often gentler on the stomach for sensitive individuals, as it doesn't release BCM-7.	Generally well-tolerated and easier to digest.	No dairy protein, so no digestion issues related to casein.
Availability	Widely available and most common dairy milk.	Growing availability but less common than standard milk.	Found in specialty stores, but less common than cow's milk.	Widely available in most grocery stores.
Nutritional Profile	High in calcium, protein, and vitamins, but varies by fat content.	Similar to conventional cow's milk.	Rich in calcium and other minerals, often with a distinct taste.	Varies greatly; fortified versions offer comparable calcium.
Primary Breeds	Holstein, Friesian, Ayrshire	Guernsey, Jersey, Gir	N/A (Species-specific)	N/A (Plant-based)

The Digestive Connection and BCM-7

The conversation surrounding A1 beta-casein and its effect on digestion centers heavily on the peptide BCM-7. When A1 protein is broken down in the gut, BCM-7 is released and can act on opioid receptors, affecting intestinal motility. This can lead to slower digestion, increased inflammation, and symptoms that mimic lactose intolerance, such as bloating, gas, and abdominal pain. Interestingly, some studies have shown that subjects who consumed A1-containing milk experienced significantly looser stools and more discomfort than those drinking A2-only milk. This highlights that for some individuals, the protein, not just the sugar (lactose), is the source of their dairy sensitivity. For these people, switching to A2 milk or other alternatives may alleviate their digestive symptoms.

Conclusion

While milk is a valuable source of nutrients for many, the A1 beta-casein protein can be a source of discomfort for others. Standard cow's milk and the many products derived from it, such as cheese, yogurt, and ice cream, are the primary foods that contain A1 beta-casein. For those with dairy sensitivities not explained by lactose intolerance, exploring dairy from different sources or specifically labeled A2 milk products offers a viable path to enjoying dairy without the side effects. By understanding the role of A1 protein and the alternatives available, consumers can make more informed decisions to support their digestive health. The key is to be aware of the source and experiment with different options to find what works best for your body. The a2 Milk Company provides more information on their specifically bred A2-only dairy products.

Frequently Asked Questions

What is the primary difference between A1 and A2 milk?

The primary difference lies in the beta-casein protein. Standard A1/A2 milk contains a mixture of both A1 and A2 protein variants, whereas A2 milk contains only the A2 protein. This single amino acid variation affects how the protein is digested.

Which cow breeds produce A1 beta-casein?

Cow breeds that originated in Northern Europe, such as Holstein, Friesian, Ayrshire, and British Shorthorn, are the primary producers of milk high in A1 beta-casein.

Does lactose-free milk contain A1 beta-casein?

Yes, unless it is specifically labeled as 'A2 lactose-free milk', most lactose-free milk is made from conventional cow's milk and will still contain A1 beta-casein protein. Lactose is a sugar, and its removal does not affect the protein content.

Can I find A1 beta-casein in cheese?

Yes, any cheese made from conventional cow's milk will contain A1 beta-casein. This includes common varieties like cheddar, mozzarella, and cream cheese.

Is A1 beta-casein an allergen?

A1 beta-casein is not considered a true allergen like a typical milk allergy, which can cause severe reactions. Rather, it is associated with a sensitivity or intolerance that can lead to digestive discomfort.

Are there non-cow dairy products that contain A1 beta-casein?

No, milk from other mammals like goats, sheep, and buffalo contains only the A2-like beta-casein protein, not the A1 variant. Human milk also contains only A2 beta-casein.

How can I tell if a product contains A1 beta-casein?

The best way is to look for products specifically labeled as 'A2 milk'. If a dairy product is not labeled, it is safest to assume it is made from conventional cow's milk and contains both A1 and A2 proteins.