A total of at least 286 participants will be randomized to either a 16-week rapid weight loss (RWL) program; \[an 8-week low-energy-diet (\<1000 kcal/day) - followed by an 8-week gradual increase in energy intake (4 weeks \<1300 kcal/day and 4 weeks \<1500 kcal/day)\], or a 16-week gradual weight loss (GWL) program (controls); \[estimated total energy expenditure minus 800-1000 kcal/day\]. Thereafter, all participants (both groups) will undergo a 36-week comprehensive weight maintenance program.
