Think the debate over milk’s nutritional value is just a veggie-vs.-animal-foods battle? Well, now there’s a more complex and interesting debate pitting A1 against A2. Confused? Read on.
Most consumers are aware of the controversy surrounding the nutritional benefits of so-called “raw milk.”
Proponents of raw (unpasteurized) milk claim that its health benefits are far superior to pasteurized milk — to the extent that many advocates insist that the homogenized, pasteurized stuff 99.99 percent of us drink can cause all sorts of health problems.
That debate pits an isolated fringe group against an overwhelming majority of both scientists and consumers, and when on occasion raw milk containing pathogenic bacteria sickens somebody, it only reinforces the extremist stance of the people opposed to the most reliable food-safety technology ever developed.
But like a belief in alien abduction, there’s no convincing raw milk devotees that they should re-examine their beliefs.
Now, however, there’s another milk-related controversy, one seemingly more plausible, but one also being flogged by a small cadre of researchers and their media cheerleaders. It’s based on the theory that many people who suffer from lactose intolerance are not allergic to lactose. Instead, they’re unable to properly digest the A1 protein typically found in milk from Holstein cows, unlike the A2 protein that predominates in Jersey and Guernsey breeds.
The A1 and A2 proteins are different forms of beta-casein, which comprises about 30 percent of milk’s protein content.
But you already knew that.
What I didn’t know, however, is the A2 backstory. It seems that A2 beta-casein mutated into A1 thousands of years ago among certain European dairy herds. Millennia later, cows can now be classified either as pure A2, A1-A2 hybrid, or pure A1. (Both human breast milk and goat’s milk contains only A2 beta-casein).
This controversy over the alleged ill effects of A1 milk first heated up in New Zealand some 20 years ago, thanks to research by Prof. Robert Elliott at New Zealand’s University of Auckland. Elliott theorized that the consumption of A1 milk might explain the high incidence of type 1 diabetes among Samoan children in New Zealand. According to a current story in Mother Jones magazine, he analyzed per-capita consumption of A1 milk and the incidence rates of diabetes and heart disease in 20 different countries and discovered strong correlations.