Great question. And the answer is “yes” and “no.” The sexual life has two pieces: mechanics (erections and stuff) and desire (libido).
Good mechanics is largely a matter of good blood circulation. All those pills for men (Viagra etc) just send blood to the naughty bits. (If you have an erection that lasts more than 4 hours, call me… I’d like to hear about it.) They have no impact on desire except to the extent that having good mechanics may make you feel perky. For some, the mere sight of those little blue pills is an aphrodisiac.
Libido, alas, is on the biological time line – the 30% of aging you cannot do much about. Men lose testosterone and increasingly aren’t interested. Saddest thing in the world. BUT libido is mysterious.
If you suddenly lose 35 pounds and don’t look scary with your duds off, there may well be an impact on your desire to take your duds off. There you go.