It's a let's agree to disagree situation.
Some of my family members lectured me with similar arguments on gym and whey powder, like, you will be so fat and unhealthy from all the liver-tiring protein when you quit. I tried to make a point that it's a lifestyle which means I won't quit (unless I get really broke or severely injured), and also whey is healthier than their sources of protein which are high in fats (sausage, beef/russian salad, the norm around here), all the talk to no avail. I don't necearily advocate whey protein, but in this context it was a better alternative. Nobody cooks lean meat without adding a large amount of oil to it. I guess it's cultural.
I'd never start a topic on aas in the family, it's way too personal.
“The thing women have yet to learn is nobody gives you power. You just take it. ” - Roseanne Barr