Oh yeah, does he work out too? If not, tell him that it'll give him more energy, a better mood, more confidence and help his brain work better and his performance at work (and elsewhere) improve. It'll basically deliver what those Enzyte commercials promise (well, except for the bigger wang).
And maybe that "lovin' feeling" of yours will be helped along by his developing muscles.
a fine and enviable madness, this delusion that all questions have answers, and nothing is beyond the reach of a strong left arm.