Just to start off with a disclaimer that this is not meant to be a comprehensive article but rather an overview.
Metabolic Adaptation (or metabolic damage as we like to call it) is basically when your metabolism is changed or altered to function under circumstances that have deviated from what it was used to. So the typical example of this would be a successful diet where a person loses weight nicely and then suddenly stops showing the results it once was. So here is the reason behind that change from losing weight to not:
The weight loss results in a lower total daily energy expenditure. The more you weigh, the more calories your body requires. As you lose weight, your body suddenly requires less calories. This means that suddenly your body has gone from requiring a higher maintenance (simply to maintain weight) calorie amount to a lower maintenance calorie amount.
So what does that mean? Basically, to maintain your pre-diet weight you required a certain amount of calories, after diet weight your body will now require less calories to maintain your new current weight.
This would lead you to assume that another decrease in calories can make you lose weight again? And you are not wrong per se, but you won’t be able to keep decreasing your calorie intake forever you will eventually eat more or die of starvation.
That adjustment your body has made of decreasing the amount of calories it requires is done through various mechanisms which include hormonal adjustments in leptin and ghrelin, adjustment to your (BMR) basal metabolic rate and your (NEAT) non-exercise activity thermogenesis as well as a greater ability for your body to convert and store energy.
Suddenly you have a mix of mechanisms that make it extremely difficult to lose weight.
BMR and NEAT go down, so less calories used.
Ghrelin (hunger hormone) goes up making you more hungry. Ghrelin is a real piece of work!
Lastly, increased ability to store energy. Basically your body stores fat more than before. These factors are not alone, but rather the factors easily explained.
As a result you have metabolic adaptation. This is reversible, but it’s easier to prevent than it is to reverse.
How to prevent? That’s a whole blog in its own! But a little excerpt to wet your apetite…
After a diet where you lose weight, you need to reverse diet, maintain weight for a good couple of weeks, and then re-establish what your maintenance calories are. It can become quite complicated, but largely manageable by an experienced dietitian, trainer or coach.
If you have any questions or want us to burrow down into the details let us know and we can help you.
by Theo Pretorius