I have seen a lot of info on this, and it appears legitimate. I'm on a long-term program to gradually reduce my weight, but I will not be going to the extreme of giving up beer and the occasional desert. I'm sure I'll never get near my "ideal" weight, but hopefully I can still realize some long-term benefits.
My bodyfat is low, but I carry extra muscle mass which apparently still causes your organs and metabolism to work harder. Not to mention the joint stress from extra weight...I about cured my minor knee and ankle issues by losing 5 pounds (and glucosamine/chondrotin).
I'm going to gradually ramp up the aerobic stuff a bit and shift to higher reps and lower weights when lifting. I'm also trying to eat more fruits and veggies.