In Part I, I discussed the history and problems surrounding pasteurized milk in the early 19th century. To understand why perhaps even raw cow's milk isn't good for us, we need to go much farther back in history.
At some point between the 1300s and the 1500s, our ancestors started switching from goats milk to cow's milk. It is probable that they made the switch for the larger milk producing udder of a cow. Whatever the reason, the change in milk came with a change in casein fraction - the sticky, glue-like protein in milk - and thus, unknowingly moved from an A2 Beta-Casein (A2) to an A1 Beta-Casein (A1). As Dr J Symes writes, "The difference in the casein fraction is subtle but immunologically immense." (1)
This difference in casein types helps to explain why some people who cannot tolerate cow's milk, can tolerate goat's milk. Cow's milk is made up of 80% casein, and of this casein, 75% of it is A1 Beta-Casein (2). Interestingly enough, different breeds of cattle also produce different types of casein. The Brahma produces the A2 casein, while the cows most commonly used in North American for dairy - the Jersey, Guernsey, and Holstein - contain the difficult to digest A1 casein.
Why is casein a problem? As I mentioned above, casein is a glue-like protein, and when it gets to the intestines it has the tendency to bind to our intestinal villi, the little finger-like projections which are there to help increase absorption of nutrients. If the villi cannot do their job, our bodies become malnourished and that leads to a whole host of other problems. The immune system's response is to shrink the damaged villi to prevent them from attaching to any more milk protein. This eventually leads to increased gut permeability or leaky gut, which allows particles of food enter the blood stream. When this happens, we set ourselves up for all sorts of food sensitivities, and much more serious auto-immune responses.
One particular type of casein, Beta Casomorphin 7 (BCM7) has been implicated in triggering Autism, Type-1 Diabetes (3), Multiple Schlerosis and Schizophrenia. Did you notice the 'morphin' in Casomorphin? This protein breaks down into an opioid and is responsible for the addictive-like behavior we experience in food allergies - I talk more about that here. Food allergies to BCM7 can cause similar behavioral responses to someone addicted to Heroin. What's more, researchers have known for years that children who receive cow’s milk in the first five days of their lives have a 40-50 times higher rate of Type-1 Diabetes than the general population (4)!
Learning all of this information terrified me. I wondered what kind of damage had I done to my body? My family's? The information also saved me, by helping me to understand why I was having my own digestive battles, why I developed food sensitivities to everything, why my hair was falling out, why I was constantly fatigued and had memory problems. Not only was I malnourished, my intestinal villi were extremely damaged and I was suffering from a severely leaky gut. I felt ill and irritable all the time. I wasn't just lactose intolerant - it was simply an indicator of a much larger problem. I feel fortunate to have found this information before the onset of something more serious.
More importantly, this information was powerful. Knowing that I could spare my son from my own fate or worse, spurred me into action. We're all hearing about the rise in Autism, ADHD, and other learning disabilities and enough information out there implicates diet as a large part of the problem. The removal of casein from the diet has show remarkable behavioral differences in children suffering from these disorders. I noticed that the removal of casein from my son's diet made a difference too.
The hesitancy for most people, as it was for myself, is what do we give our children instead so that we know they're getting enough calcium and vitamin D. Part III will lay to rest some of the myths floating around about cow's milk.
(3) Elliott R et al (1999). Type I (insulin-dependent) diabetes mellitus and cow milk: casein variant consumption. Diabetologia, 42:292-296.