Welcome to Dr. Warrick's podcast channel. Warrick is a practicing cardiologist and author with a passion for improving care by helping patients understand their heart health through education. Warrick believes educated patients get the best health care. Discover and understand the latest approaches and technology in heart care and how this might apply to you or someone you love. Hi, my name is Dr. Warrick Bishop and I'd like to thank you for joining my podcast channel. Today I'd like to talk about something that you may have seen at your local supermarket or corner store and that is a 2 milk. What is it? Why do we bother about it? And is it for you? Well, I don't know that much about. milk and milk proteins, but beta casein is the main protein that we find in milk. This is a bit of history that I would never have known, but about 8,000 years ago, some characteristics of beta casein began to change, and that occurred with a mutation of one of the 200 plus amino acids that are required for its genetic profile. It turns out that with that change, A1 milk was generated. And A1 milk, through history and through breeding practices and so forth, ended up in Europe and then subsequently around the remainder of the Western world. So, we've ended up with... A1 milk cows, not A2 beta casein milk cows. Well, there is some theoretical and observational data that suggests that A1 beta casein may have an effect on the gut that's different to A2 beta casein. So hence there's a difference in these two proteins. which makes sense, not a big difference, but a little difference. And importantly, they appear to alter the release of a subsequent substance called opioid beta-casomorphin in the small intestine. This opioid beta-casomorphin has been linked to impaired gastrointestinal function, the gut contracts, and also in the number of inflammatory cells that might be seen in the gut. Well, now we have a potential, or at least theoretical mechanism, which differentiates A1 milk, what most of us are drinking, to A2 milk, perhaps the good old-fashioned stuff, which is now not so readily available. researchers an opportunity to look into A2 milk to see if there are differences between it and A1 milk. So it turns out that there's been a bit of research and observational studies looking at A1 milk consumption and trying to understand if those changes in the gut, which it's fair to say we're starting to understand that gut, and gut microbiome are becoming more and more important, but these observational studies looking at A1 milk consumption have suggested perhaps an increase in type 1 diabetes, perhaps autism, perhaps coronary artery disease, and even schizophrenia. So you say, well, let's get some A2 milk happening here. Well, There have been some criticisms of the A2 milk research, and that is primarily that it's been funded by the company. That, of course, is a double-edged sword. If you weren't producing A2 milk and then started to produce it, of course you'd want to justify that it worked okay, otherwise there wouldn't be a market for it. But the fact that that research is funded by the company certainly casts... a shadow of doubt over a possible unbiased presentation of the facts. It turns out that an independent study in 2014 was unable to show the same link between A1 milk and human health, although did note that there was some slight changes in inflammatory markers when A1 milk was consumed by mice. Well, does that help us? Some further debate around A1 and A2 milk suggested that it's lactose intolerant people who may benefit more from using A2 milk. And so some research around about 2017 using 600 Chinese adults in a randomized crossover trial did look at this. And in fact, for that group of people, suggested that A2 milk, in a double-blind, randomized, crossover trial, which is the real deal, A2 milk reduced such gastrointestinal symptoms as bloating and abdominal pain in comparison to A1 milk. Well, I guess the question is, does that help us if we're not lactose intolerant? And to a large degree, the jury is still out on that. Interestingly, there was a critical review in 2006 evaluating A1 and A2 milk and trying to establish the legitimacy of the claims. And in fact, in one of the reviews undertaken, the author or the paper, and I quote, says, I quote, was ingenious. If the scientific evidence had worked out, it would have required huge adjustments in the world's dairy industries. Close quotes. In a funny twist, in a funny and interesting twist, the author who produced that review and provided that quote I just gave was subsequently found out to be a consultant. for the New Zealand dairy industry. And I wonder if there was just some degree of interest in the dairy industry not looking to change. So where are we now? We're in 2018, 2019, and looking ahead. At the moment, it would be fair to say that there are no clear-cut trials for the general population to suggest that a two-milk is preferable over A1 milk. There is some data that suggests if you're lactose intolerant, you may benefit from taking A2 milk over A1 milk. But remember, if you're lactose intolerant, you probably won't be drinking milk at all. What my thoughts would be is that if you think that you may have some issues with milk, then you may experiment with A1 and A2. And if at all possible, I'd suggest you try and blind yourself to those challenges. So get your husband, wife, friend, children, whoever it might be, to blind you between A1 and A2 and try and observe those differences over a 24-hour to 48-hour period. For my own approach to dairy, I don't drink a lot of dairy. I use it for coffee, but not a great deal else. In terms of what I buy, I tend to buy milk from local producers in the state where I live in Tasmania. I know these cows have been grass-fed, high-quality milk without any additives or hormones or antibiotics. produced straight from the cow and to the supermarket or corner store. I personally like supporting the small milk producer that's local. Well, I hope I've given you a little bit to chew over as a cow might chew its cud. I hope you understand now A1 and A2 beta casein proteins. and understand that there is some theoretical differences between the two, and whether you choose one or two at the moment is probably up to you. If you are lactose intolerant, then there is some data which looks like it was a well-performed trial to give you some reassurance you may get less symptoms using A2. I'm going to wrap it up there. I hope you enjoyed that. Hope you found it interesting. If you have any suggestions for other podcasts, please feel free to let me know. Take care and bye for now. You have been listening to another podcast from Dr. Warrick. Visit his website at drWarrickbishop.com for the latest news on heart disease. If you love this podcast, feel free to leave us a review.
