Leucine, for instance, is well known to boost muscle, which is why it’s found in large quantities in the protein drinks that bodybuilders often chug before, during, and after workouts. But that muscle building is coming in part because leucine is activating mTOR, which essentially calls out to your body, “Times are good right now, let’s disengage the survival circuit.”28 In the long run, however, protein drinks may be preventing the mTOR pathway from providing its longevity benefits.
