Ahh, a traveler after my own heart - a foodie.
My general plan is to lose 5-10 before you leave, planning on gaining 10-15lbs, for a net gain of only a few lbs. Otherwise, trying to fit into your pants on the last day before going to the airport can prove to be quite the challenge!
Interested to know how the ultra long haul is. 16 hours is a long time to spend in an aluminum tube. But in F, I imagine it to be quite tolerable and even enjoyable!