I have never seen a medical chart that recommends 160 lbs for a six-foot tall male. Your reference to 'body-mass index' is on-target, of course, but 160 lbs is not likely to be healthy for ANYone (small-boned or large-boned) who is 6'00". You are setting the OP up for anorexia. Most charts I have seen recommend 165-170 for a small-framed person, 170-175 for a medium framed person, and 175 to 180 for a large-framed person. I weighed 175 in the Army and looked like a refugee from Dachau--I want to be at least 10 lbs above that weight. If this person is truly as athletic as they suggest, they probably also need to figure on carrying just a few pounds more than the 'charts' suggest, just to look and feel healthy.