You may already have noticed some milk cartons that boost claims like “easier to digest” or “helps avoid discomfort”, those most likely contain A2 milk products. “A2” refers to the occurrence of A2 beta-casein protein instead of A1 beta-casein, both of which naturally occur in milk and only differ in one single amino acid. This amino acid is simply a minor change in genetics, but it ultimately affects our gut health and how well we can absorb consumed milk.
A2 milk is generally more easily digested and minimizes food reactivity symptoms such as bloating, gas, indigestion, and skin irritation. People whose digestive system react negatively to milk can show symptoms such as diarrhea, bowel irregularity, belly pain, and bloating.
Research shows that by switching to A2 cow’s milk, individuals who formerly had problems digesting milk can benefit from the many advantages. As part of our Product Focus: A2 Milk in this article, we summarize various studies that have investigated the differences and effects of A2 milk.
Less bloating and digestive pain
A study conducted by Curtin University published in The European Journal of Clinical Nutrition (2014) carried out the first human pilot study on A2 milk products, with subjects reporting less bloat and pain than digesting A1 milk.
Influence on cognitive behavior
A study published in the Nutrition Journal in 2016 found that milk consumption containing A1 beta-casein was associated with increased gastrointestinal inflammation, worsening of post-dairy digestive discomfort symptoms, delayed transit, and decreased cognitive processing speed and cognitive accuracy. Because the elimination of A1 beta-casein attenuated these effects, some lactose intolerance symptoms may stem from inflammation it triggers and can be avoided by consuming milk containing only the A2 type of beta-casein.
Source: Nutrition Journal, 2016: Effects of milk containing only A2 beta-casein versus milk containing both A1 and A2 beta-casein proteins on gastrointestinal physiology, symptoms of discomfort, and cognitive behavior of people with self-reported intolerance to traditional cows’ milk.
More suitable for lactose-intolerant individuals
The participants in this next study were lactose-intolerant. The results reinforce the research mentioned above. Milk containing only A2 beta-casein protein produced fewer gastrointestinal symptoms compared to regular milk, supporting the idea that A2 milk is suitable for lactose-intolerant individuals. The amount of lactose in A1 and A2 milk is the same. However, some people feel that A2 milk products cause less bloating than A1 milk. In fact, studies indicate that milk components other than lactose may cause digestive discomfort.
Less severe gastrointestinal symptoms
A paper published by the Journal of Pediatric Gastroenterology and Nutrition in 2019 provides strong evidence that A1 beta-casein relative to A2 beta-casein negatively affects both digestion and cognitive performance. Subjects who consumed milk containing only A2 beta-casein had significantly less severe gastrointestinal symptoms, reduced stool frequency, and stool consistency improvements compared with subjects consuming conventional dairy.
Lower gas production
A study with the title “Current developments in nutrition” published in 2020 evaluated the tolerance of single meals of milk containing different A1 and A2 beta-casein levels compared to lactose-free milk. It was further determined if lactose digestion was affected by A2, high A2 (Jersey) and high A1 (commercial) beta-casein milk.
Source: Current developments in nutrition, 2020: A Single Meal of Milk Containing A2 Β-Casein Causes Fewer Symptoms and Lower Gas Production than Milk Containing Both A1 and A2 Β-Casein Among Lactose Intolerant Individuals
Want to know how A2 has emerged? Click here and read on.
If you have chronic digestive symptoms, please obtain an appropriate medical diagnosis rather than attempting to self-handle. Signs of milk reactions are “non-specific”, meaning an entire host of conditions could bring them on.