I'm a product of good nutrition, cutting edge supplementation and hard training, and I'm an old guy.
Some coaches are not educated at the elite level in health and nutrition. They're not educated in how the body works from anatomy and physiology perspectives.
Doctors' positions and recommendations about drugs, procedures, surgical interventions, health and nutrition are not always based on strong scientific evidence.
Nutrition makes me puke.
I don't take supplements - I get nutrition from food.