Superior metabolic Control: The power of setpoint

When you lose weight too quickly your body fights back by lowering metabolism to defend its setpoint level of flab. The effect can be dramatic: An overweight person who has lost a lot of mass through dieting may actually burn fewer calories than someone of normal weight.

In one study, a group of non-obese men and women who weighed an average of 138 pounds needed about 2,280 calories per day to maintain either weight. A group of obese men and women weighing an average of 335 pounds needed 3,651 calories a day, but when they dieted down to 220 pounds, they needed only 2, 171 a day to maintain this new weight -- 100 calories fewer than the lean subjects! The metabolism of the formerly obese subjects had been depressed by dieting to below the level of a 138 non-obese individual.

As you might expect, some of the drop in metabolism was due to muscle loss which could have been prevented if the subjects had lifted weights and eaten 0.8 grams of protein per pound of bodyweight each day. But more was found to be due to sluggishness: If you lose weight too quickly, your body will drastically lower it's rate of caloric burn, essentially going into "famine mode". That's why a gradual approach to fat loss is recommended.

From Muscle & Fitness Hers Dec / Jan 2001 pg. 69

Nat

Good one!

There's nothing worse a dieter can do to sabotage their weight-loss than losing muscles. Some are happy to see the scale drop, but if the weight lost is muscle, you end up fatter than when you started even if you're 20 lbs lighter.

Wa'il