I've recently read that ultra accel promotes healthier longer lives. is it safe to take and why isn't the medical profession shouting about it?

Waiting for science: Ultra Accel and similar products are not medications approved by the FDA. That means such products are probably not vigorously tested for interactions and side effects like real medicines are. So, that means nobody really knows what benefits or side effects there are. If an Ultra Accel user hears of some interaction or thinks she is getting a side effect, she can visit her primary care doctor.