Digestion, Diarrhoea | May 10, 2017 | Author: Naturopath
Selecting which milk is right for you among the variety of milk and milk alternatives on the supermarket shelves can be a daunting task. With so many health claims, consumers find themselves confused and even frustrated.
One type of milk that has made headlines in recent years is the A2 milk by the New Zealand-based company, the a2 Milk Company.
A2 milk (and milk products, including yoghurt, cream, and ice cream) is said to be easier to digest than regular cow milk.
The milk is sold at supermarkets all over New Zealand, Australia, UK, the US and China.
Cows’ milk contains several types of proteins. Casein makes up about 80% of the milk proteins, while the remaining 20% consists of whey protein. Beta-casein is a class of caseins that comes in two primary types:
A1 beta-casein. Found in cattle of European origin, carrying both beta-casein type protein genes, and producing milk containing both types of the beta-casein proteins.
A2 beta-casein. Found in Asian and African cattle that carry the A2 beta-casein type protein gene and produce milk purely containing the A2 beta-casein type. It is thought to be the original gene variant of beta-casein in milk, whereas A1 beta-casein evolved later due to genetic mutation through modern farming practises.
According to the A2 Milk Company, A2 milk in Australia is produced from local cows from 28 certified a2 Milk™ dairy farms.
Digestion of A1 type can release a peptide called β-casomorphin-7, or in short BCM-7. Some researchers suggest that BCM-7 is responsible for adverse gastrointestinal effects of milk by inducing inflammation. A2 beta-casein can also release some BCM-7, but in very minimal amounts.
Most of the studies that reported health benefits from drinking A2 milk were small studies funded by the a2 Milk Company itself; thus, there may be a conflict of interest.
For example, one study compared effects of consumption of normal milk, containing a mixture of both the A1 and A2, with milk containing only the A2 type, by 45 Chinese subjects. The study found that consumption of milk containing both A1 and A2 beta-caseins increased inflammation and worsened gastrointestinal symptoms.
Similarly, a study by Curtin University involving 41 Australian participants found that those who consumed A1 milk reported more abdominal pain, bloating, and increased stool looseness.
The European Food Safety Authority (EFSA) concluded that based on the available scientific research, there is no established relationship between the oral intake of BCM-7 and any of suggested adverse health effects.
Food Standards Australia New Zealand (FSANZ) concluded that the available scientific evidence on comparative health effects of the two milks is very limited.
Those who suffer from lactose intolerance may find that drinking A2 milk, despite its similar lactose content to regular milk, does not cause them digestive discomfort. However, lactose-free milk, which does not contain lactose, is available at every supermarket.
Another option is goat’s milk.
It contains only a minimal A1 beta-casein, slightly less lactose than cow’s milk, and its fat globules are smaller, making it easier to digest.
The biggest issue with milk alternatives is the low levels of calcium. If you choose to consume a plant-based milk, it is important to make sure you get enough calcium from other sources, such as sardines, green vegetables (broccoli, cabbage, kale, spinach, green beans), beans, and sesame seeds.
Additionally, some brands contain large amounts of added sugar. Read labels and always choose unsweetened varieties.
The health benefits of A2 milk are still an open debate, and consuming A2 milk is simply a matter of personal choice.
If you suffer from bloating, stomach pain and/or cramps, diarrhoea, flatulence, and nausea after drinking milk, it may well be worth trying A2 milk. However, there is no advantage in substituting your regular milk with the more costly A2 milk if you already drink milk and do not suffer any digestive issues.
Ho, S., Woodford, K., Kukuljan, S., & Pal, S. (2014). Comparative effects of A1 versus A2 beta-casein on gastrointestinal measures: a blinded randomised cross-over pilot study. European Journal of Clinical Nutrition, 68(9), 994–1000.
Jianqin, S., Leiming, X., Lu, X., et al. (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. Nutrition Journal, 15, 35.
Pal, S., Woodford, K., Kukuljan, S., & Ho, S. (2015). Milk Intolerance, Beta-Casein and Lactose. Nutrients, 7(9), 7285–97.
Scientific Report of EFSA prepared by a DATEX Working Group on the potential health impact of β-casomorphins and related peptides. EFSA Scientific Report (2009) 231, 1–107
The a2 milk company 2017, Beta-casein milk protein, retrieved 7 May 2017,