According to this article, milk from Holstein cows might have downsides and many health consequences including diabetes.
But I am having a hard time finding more articles that bring up the same topic.
As per the article, the difference in digestion between the A1 protein (Holstein) and A2 protein (Jersey, Guernsey, most Asian/African breed cows) has a host of health impacts. Most notable, reduction in autism symptoms, possible schizophrenia reduction and less chance of developing diabetes.
Are there any studies to corroborate these claims, or is this merely the marketing hype that the article states is possible?