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Eat Less, Burn Less — The Body Fat Thermostat Part 5
Cutting Calories Cuts your Metabolic Rate — science.
The amount of body fat we carry is regulated much like a thermostat (see The Body Fat Thermostat Part1). If you eat less, you’ll become more hungry (see Part2 — The Science, and Part 3 — Understanding Hunger), which will eventually make you want to eat more.
If you white knuckle it and use all your willpower to force yourself to continue eating less despite the increased hunger, (driven by hormones), then your body will reduce the Calories Out so that Body Fat is maintained. (See Part 4). This corrects the perturbation to the system in a homeostatic fashion.
These basic facts have been confirmed by medical research over the past century, although nobody seems to ever want to tell you this inconvenient fact.
The Energy Balance Equation
To lose weight, it appears simplistically that one of the keys is to Eat Less (reduce Calories In). But this simplistic view is completely wrong. If eating fewer calories causes you to burn fewer calories, then the equation is now balanced without loss of body fat. You need to know what happens to ‘Calories Out’ when you decrease ‘Calories In’.
If you eat less, your body burns less, and you will not lose body fat.
This in no way violates the ‘First Law of Thermodynamics’ where energy (calories) cannot be created or destroyed. Eating fewer calories will only result in loss of body fat IF, and ONLY IF metabolic rate (how many calories you burn daily) stays steady.
BUT IT DOESN’T.
Virtually every metabolic study of the past century confirms this. Consider a financial analogy.
Increased Revenues Doesn’t mean Increased Profits
Suppose you run a business that gives change for large bills. People give you a $100 bill and you give them 5x $20 bills. On a regular day, you might have revenues of $2000 and costs of $2000, and no profits. (Just as on a regular day, you might eat 2000 calories and burn 2000 calories).
The ‘Money Balance Equation’ says:
