Metformin did pan out, but the research seems to indicate One Meal A Day would have to be employed with it, as Metformin seems to interfere with autophagy. Lack of autophagy seems to be the biggest cause of the effects of old age, as the Western Diet pounds 3 meals a day, which means our insulin levels never drop to the autophagy activation level.

If you want that "one weird trick that doctors hate", OMAD alone is almost magical. I've been suggesting it to everyone I know just so they can do something easy and simple to get a few free years out of their fleshy meat body. Also, because of OMAD, I now spend less time prepping food, eating food, and other food-related tasks. Even if OMAD had no health effects (positive or negative), I'd keep doing it as it has freed up a surprisingly large amount of time.