My last article, the body's fat thermostat - Part 1, discussed the concept of homeostasis and how body fat is regulated like a thermostat rather than simply being the end product of calories in - calories out. The level set by the thermostat is determined by many hormones (just like most everything else in our bodies), rather than the number of calories we consume. However, it is true that the types of foods and the amounts of food will affect those hormones, but different foods, even with the same calories, have different hormonal effects. This is why counting calories is such an unsuccessful weight loss strategy.
Is there scientific evidence for the existence of this body weight set point (BSW)? Absolutely. Almost every study conducted in the past 50 years shows this. It is remarkable that very few people discuss the mechanisms of this fat thermostat as it has significant implications for weight loss. Huge.
How the body's fat thermostat works
The body weight set point (BSW) acts like a thermostat. Our bodies set a certain level of body fat and then defend it according to the equation body fat energy balance = calories in - calories out, which is always true.
If body fat is too high, then our bodies will bring it back into range by activating several mechanisms such as:
· Decreasing appetite (so we eat less)
· Increasing energy expenditure (so we burn off some of the stored calories (body fat))
If body fat drops below the BSW (when we lose weight), then our bodies will also bring it back to the original state by activating mechanisms such as
· Increasing appetite (so we eat more)
· Decreasing energy expenditure (so we store more calories (body fat))
This is crucial for weight loss because it means that successful weight loss depends on fixing the body fat thermostat that is set too high, not on reducing calorie intake (eating less) because that will cause the body to increase appetite and decrease metabolic rate.