Of course, correlation is not causation; the etiology of chronic disease is always multifactorial, meaning that factors such as diet, lifestyle and the amount of vitamin D a person metabolizes from exposure to sunlight would influence any correlations between A1 milk and chronic disease.
That didn’t slow down Prof. Elliott, however, and in a 1997 study published by the International Dairy Federation, he demonstrated that A1 beta-casein caused mice to develop diabetes. Elliott’s co-researcher, Corran McLachlan, soon after partnered with wealthy New Zealand businessman Howard Paterson to launch the A2 Corporation.
A cause, or a correlation?
Since then he’s had plenty of support and gotten lots of publicity from several self-appointed health authorities.
“We’ve got a huge amount of observational evidence that a lot of people can digest the A2 but not A1,” Keith Woodford, a professor of farm management and agribusiness at New Zealand’s Lincoln University and author of the 2007 book “Devil in the Milk: Illness, Health, and the Politics of A1 and A2 Milk,” told Mother Jones. Woodford reviewed more than 100 studies that he said suggest links between the A1 protein and the development of heart disease, diabetes, even autism.
Woodford’s stance is adamant, even though the evidence is less-than conclusive.
For instance: A 2009 study by the European Food Safety Authority reviewed the available scientific literature concerning the health effects of beta-casein in milk and concluded that, “A cause-and-effect relationship is not established between the dietary intake of beta-casomorphin-7 or [its] possible protein precursors and non-communicable disease.”
In other words, the A1 protein does not appear to be a causative agent for diabetes, heart disease and cancer, as Prof. Woodford suggested.
That conclusion prompted New Zealand’s Food Safety Minister, Lianne Dalziel, to declare the debate over A1 versus A2 milk resolved, and that it was not necessary for the New Zealand Food Safety Authority to conduct its own scientific review.
That hasn’t stopped A2 Corporation from marketing its a2 brand milk in New Zealand and Australia, where its product line accounts for about 8 percent of dairy product sales Down Under (according to the company). In 2012, A2 expanded distribution through the Tesco chain into Great Britain, where a two-liter bottle now sells at about an 18 percent premium over conventional milk.