Should you switch from ordinary cow’s milk to a2 Milk? The claim is that it does not contain a protein that’s been shown to cause unpleasant gastric symptoms associated with lactose intolerance.
Many people who have tried a2 Milk report that the symptoms they experienced after drinking ordinary cow’s milk – such as bloating or constipation and diarrhoea – disappeared when they made the switch. And in a recent Netmums poll, 85 per cent of those who tried a2 Milk said they would recommend it.
Blogger Nathalie Newman, a mum of two, runs The Intolerant Gourmand, which offers support and advice to food-allergy sufferers. She heard about a2 Milk via other bloggers, and was inspired to try it for herself.
“I’ve had IBS [Irritable Bowel Syndrome] for about 17 years, which has caused symptoms such as bloating, cramping, sickness and a general feeling of malaise,” she says. “It was horrible. I was prescribed Colofac tablets [a common medication prescribed for IBS], and took peppermint capsules and tea, but nothing was very helpful.”
Newman decided to do a four-week trial of a2 Milk two years ago, and says: “Within a week, the difference was incredible. I was suffering no bloating or cramping. It tasted like normal milk – it was creamy and you can cook with it, normally too. I’ve never looked back since – and I am a huge advocate of it. Drinking a2 Milk works.”
So does the science back up the anecdotal evidence? The majority of European cows produce milk containing a protein called the A1 beta casein protein. The cows that make a2 Milk produce milk which contains A2 beta casein protein instead. It may not sound like a big difference, and indeed it makes no difference to the taste or nutrition, but as none other than the European Food Safety Authority (EFSA) has confirmed, it can make a difference to our tummies.
The EFSA, which provides independent scientific advice on emerging and existing risks in food safety, reviewed the research underpinning the role of different beta casein proteins in health and disease in 2009. Its paper conclusively accepts that A1 and A2 beta casein proteins are digested differently by our bodies.
Clinical dietitian Rick Miller explains that scientists began research into the different proteins about 40 years ago. “Physiological effects such as gastric motility, inflammation and possibly a link with certain illnesses have all been explored,” he says.
In 1997, Japanese researchers found that some people seemed to struggle to digest A1 protein more than others. One theory was that the A1 protein could be inhibiting the digestion of lactose, the sugar in milk, thus causing people to feel uncomfortable or even to worsen IBS.
When New Zealand research scientist Dr Corran McLachlan learned that some cows produced milk that contained only A2 proteins – and this could be determined by a simple genetic test of an individual cow’s hair – it was a breakthrough. Just by choosing the right cows, milk could now be produced that only contained A2 beta-casein.
The first human clinical trial looking at digestion took place at Curtin University in 2014. Those who consumed 100 per cent A1 protein-containing milk suffered inflammation, bloating and discomfort, and a tendency towards constipation. Those who drank milk containing only A2 protein had none of these symptoms.”
A follow-up trial was published last year in Shanghai, which was particularly significant as the Chinese population has the highest proportion (up to 90 per cent) of people with milk intolerance in the world.
In addition to testing both regular cow’s milk and a2 Milk in the double-blind study, the participants also swallowed a smart pill – a tiny device designed to take pictures of inside the gastric tract to monitor temperature, acidity and measure transit time.
The results once again showed that drinking A1 protein-containing milk led to bloating, pain and discomfort, but those who drank milk containing only A2 protein had no symptoms. “It was revolutionary,” says Miller. “In this study, even those who were confirmed as lactose-intolerant could digest it.”
So it turns out that not all proteins are good guys after all. Who could have thought that one little protein in milk would be causing so many problems? But at least now there’s a solution that doesn’t involve dropping dairy altogether…
Not all milk is the same
a2 Milk is real cow’s milk that’s naturally easy to digest.
Switching to a2 Milk has helped people who have previously had difficulty with traditional cow’s milk.
Find out more about with the symptoms of IBS and other adverse reactions to traditional cow’s milk.