I'm not a member but have been alerted to a thread discussing A2 milk. I'm not connected with A2 but follow the topic very closely. If you like, you can feed this info in to the thread.
A2 milk is believed to have significant health benefits but:
(1) They are not the kind that body builders would probably be looking for, since A2 milk does not have (and is not claimed to have) greater nutritional or energy value than standard milk;
(2) The health benefits, although fairly well established, are not ABSOLUTELY PROVEN to the point where they can be openly advertised under consumer laws. But they are pretty widely accepted, and arise from the clearly established fact that in countries where milk is predominantly A2 there is a much lower incidence of diabetes, coronary heart disease and some psychiatric conditions (e.g. autism, schizophrenia) than countries such as Australia and NZ where the milk largely contains the A1 protein due to the breeding genetics of the cattle population. It's a bit like the old days when the tobacco industry said "we know most people who die of lung cancer are smokers, but that doesn't prove there's a connection". It'll take years to prove that A2 is safer, but the statistical evidence is awfully strong, and science is now beginning to understand how A1 milk can trigger these disease conditions in susceptible individuals.
And although the A2 people don't say people with a lactose alergy are more likely to be able to drink A2 milk, there are lots of people who've tried it and say that is the case.
Hope this may be helpful. More information can be seen on the site <
www.a2corporation.com>