In order to undergo significant weight loss, we need to establish a new balance between the calories we consume and the energy we spend burning these calories. A part of our brain, called the hypothalamus, regulates this balance by sending hormones through our body to regulate our hunger levels and controlling our metabolism – how quickly we expend the caloric energy we consume.
The hypothalamus helps our body find a “weight set-point” and adjusts our metabolism and hunger levels to best maintain this point. This bodily function is precisely why moderate weight loss can be difficult to achieve; the body is resisting this weight loss because it wants to maintain the equilibrium of the “weight set-point.”
For people who are obese and lose significant weight, the body continues to adhere to their bodies’ original “weight set-point.” People who are obese generally have higher resting metabolic rates (the rate at which the body burns calories while in rest). After losing weight, however, the body’s resting metabolic rate drops dramatically and the hypothalamus sends more hunger signals through the body – both of which will cause weight gain.
This is ultimately what happened to the contestants of the show The Biggest Loser. Although each of these contestants lost significant percentages of their body weight on the show, almost all of them struggled to maintain their new weight in the six years following the show.
What doctors now advise for individuals striving to lose weight, and maintain this weight loss, is to perform strength exercises that preserve muscle mass and help raise the body’s resting metabolic rate. This should be, however, combined with consistent exercise and a permanent decrease in calorie consumption.
As with any other physical development, weight loss is a process that should be maintained long term, not accomplished within the matter of a few months.
