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September 16, 2024
A2 milk has gained popularity in recent years as a healthier alternative to traditional cow’s milk, largely due to its potential to be easier to digest. While regular milk contains both A1 and A2 beta-casein proteins, A2 milk is specifically produced to contain only the A2 protein.
This has raised interest in A2 milk’s possible digestive benefits, along with its overall nutritional profile.
In this article, we’ll explore what A2 milk is, how it differs from A1 milk and the health benefits supported by scientific studies.
What Is A2 Milk?
A2 milk is a type of cow’s milk that contains only the A2 beta-casein protein, rather than the more common A1 beta-casein. Casein proteins make up about 80% of the total protein in cow’s milk, with beta-casein being one of the major components.
A1 and A2 proteins differ by just one amino acid, but this small variation is thought to make a significant difference in digestion.
Historically, cows primarily produced A2 beta-casein, but a genetic mutation introduced the A1 protein into dairy herds.
Some research suggests that A2 milk may be easier for people to tolerate, particularly those who experience discomfort after drinking regular milk but are not lactose intolerant.
There are farmers who now breed cows specifically to produce milk containing only the A2 protein, catering to consumers who seek milk that may be gentler on the digestive system. Cows that naturally produce A2 milk include breeds like Guernsey and Jersey.
A2 vs. A1 Milk
Traditional cow’s milk contains a mix of both A1 and A2 beta-casein proteins.
A1 protein, when digested, releases a peptide called beta-casomorphin-7 (BCM-7). This peptide has been linked to gastrointestinal discomfort and symptoms, such as bloating, gas and diarrhea, in some individuals.
A2 milk, on the other hand, does not release BCM-7, which may explain why it can be easier to digest for some people.
Here’s a breakdown of the key differences:
- A1 Milk: Contains both A1 and A2 beta-casein proteins. Upon digestion, A1 protein produces BCM-7, which may cause digestive issues in some individuals.
- A2 Milk: Contains only A2 beta-casein protein and does not produce BCM-7 during digestion, potentially reducing digestive discomfort.
A2 Milk Benefits
A2 milk offers a variety of health benefits, many of which stem from its potentially superior digestibility compared to regular milk. Here are some of the top A2 milk benefits.
1. Improved digestibility
Research has shown that A2 milk is easier on the digestive system for people who are sensitive to regular cow’s milk but are not lactose intolerant.
In a 2019 randomized, double-blind, crossover study conducted in China, children who drank A2 milk in place of the standard milk with both A1 and A2 proteins reported fewer gastrointestinal symptoms after just five days. They also saw cognitive benefits after making the switch.
In another study published in the Journal of Cancer Prevention, participants who drank A2 milk reported fewer digestive symptoms, such as bloating, compared to those who drank regular milk with A1 protein. Participants found that A2 milk was associated with less abdominal pain and softer stools, for instance, compared to regular milk.
The absence of BCM-7 in A2 milk is believed to be the key reason behind this effect.
2. Reduced inflammation
Some studies suggest that A1 protein may contribute to inflammation in the gut. By eliminating A1 beta-casein, A2 milk may help reduce this inflammation.
In fact, some evidence suggests that A2 milk may have anti-inflammatory properties. For instance, animal studies have shown that A2 beta-casein may lead to less intestinal inflammation compared to A1 beta-casein.
A 2017 study found that participants consuming A2 milk had reduced markers of intestinal inflammation compared to those who drank A1 milk. This could benefit individuals with mild inflammatory conditions affecting the gut.
3. Potential cardiovascular benefits
A2 milk may also have positive effects on heart health.
Research has linked BCM-7, the peptide released by A1 milk, to negative impacts on cardiovascular function. In contrast, A2 milk, which does not produce BCM-7, might be a better choice for those looking to support heart health.
4. Beneficial for lactose sensitivity
Although A2 milk is not lactose-free, many individuals who believe they are lactose intolerant may find that they can tolerate A2 milk. A study published in 2020 revealed that some people who experience lactose intolerance symptoms with regular milk may drink A2 milk without the same discomfort.
Additionally, this type of milk might contribute to overall gut health by being more compatible with the digestive system. Research into A2 milk and gut microbiota is ongoing, but some of the current findings suggest that it may be less likely to disrupt digestion.
5. Potential cognitive benefits
While more research is needed, some studies suggest that A2 milk consumption may be associated with improved cognitive function, particularly in individuals with milk intolerance.
For instance, in the study mentioned above conducted on Chinese children, switching from regular milk to milk with only A2 casein protein resulted in cognitive benefits, according to researchers.
6. Possible reduction in type 1 diabetes risk
Some epidemiological studies have found a correlation between A1 milk consumption and increased risk of type 1 diabetes. However, this link remains controversial and requires further investigation.
7. Provides key nutrients like protein
A2/A2 milk features an impressive nutrient profile, like regular dairy milk. One cup (240 mL) of 2 percent reduced-fat A2 milk, for example, contains 130 calories. Macronutrients are 12 grams of carbohydrates, 5 grams of total fat (3 grams of saturated fat) and 9 grams of protein.
For the vitamins and minerals, one cup of A2/A2 milk contains roughly 25 percent daily value (DV) of calcium, 12 percent DV of vitamin A and vitamin D, and 8 percent DV of potassium.
These characteristics are why you can find this type of milk in certain supplements, such as whey protein.
Risks and Side Effects
While A2 milk is generally considered safe and has numerous potential benefits, there are a few things to keep in mind:
- Not Lactose-Free: A2 milk still contains lactose, the sugar found in milk. If you’re lactose intolerant, A2 will not necessarily alleviate all symptoms, although it may reduce some digestive discomfort related to the A1 protein.
- Allergies: Those with a cow’s milk allergy should avoid A2 milk, as it still contains casein and other milk proteins that can trigger allergic reactions.
- Limited Research: While initial studies show promise, more research is needed to fully understand the long-term benefits and effects of A2 protein milk.
Conclusion
- A2 milk provides a promising alternative to regular cow’s milk for individuals who experience digestive discomfort but are not lactose intolerant.
- By excluding the A1 beta-casein protein, this milk may reduce digestive issues, inflammation and other potential negative effects associated with traditional milk.
- While more research is necessary, the current evidence suggests that A2 milk could be a beneficial addition to your diet, especially for those with mild lactose sensitivity. However, it’s essential to consider any allergies or intolerances to milk before making the switch.
- As with any dietary change, it’s advisable to consult with a health care professional before incorporating A2 protein milk into your diet, especially if you have existing health conditions or concerns.
- As the popularity of this type of milk continues to grow, ongoing research will likely further clarify its benefits and help more individuals make informed dietary choices.
