Came out of grad school at a lean and mean 215 lbs.  At 5'11", I thought that was a little much.  Changed my eating habits (no more warm beer and cold pizza), bought a jumprope, and 10 months later here I am down to 175. 

Now I am lifting more weights and trying to tone and maintain.  The gym has actually become the highlight of my day, most days.  One thing about working for the federal government is absurdly cheap, excellently maintained gyms in the basement.

Another unexpected benefit of this lifestyle change is that I finally learned how to cook.  Necessity is the mother of invention...