On a practical level, I'd be pretty concerned about the cancer risk from all those long-haul flights. Pilots are considered "radiation workers" and receive doses of radiation (from cosmic rays) that put them in the top 5% of exposed workers. Fortunately the overall increase in risk is only about 1% but of course their hours are strictly limited. But if you were flying basically all day, every day, without breaks, for years on end, I'd think that the increased risk would become non-negligible.

On the plus side, you'd never be able to smoke and if you restricted yourself to red wine you might do yourself some good (if myths are to be believed)!

http://hps.org/publicinformation/ate/q941.html