One of the most common but controversial topics in the dieting world is metabolism. We’re always hearing about things like “slow or fast metabolisms” and “metabolic damage” and there are even “metabolic reset” diets, which claim to give miraculous, one-size-fits-all solutions to boost your metabolism. So is all this talk about fixing your metabolism the secret to sustainable weight loss? Until recently, this was a difficult question to answer but three new studies have looked at how weight loss affects metabolic rate and they’ve all come to similar conclusions.
Firstly, just before we move on, it’s silly to discuss this matter any further without getting our terms straight. When most people refer to metabolism, what they mean is “metabolic rate”. The metabolism consists of all of the thousands of things the body must do to survive and function well - so we’re talking about how the body uses calories as fuel (not the problems caused in the long term by a poor diet, like diabetes, etc). Metabolic rate is a measure of how many calories the body burns to keep the metabolism ticking along.
When dietary intake is restricted, the body slows its metabolic rate and becomes more efficient. How? Well, it burns fewer calories off as heat and restricts excess movement when sitting or sleeping, along with other small adjustments to “conserve fuel”. The degree to which your body reduces metabolic rate will depend upon different factors related to your genetics and the amount and types of foods you eat.
So it is not controversial that the body slows metabolic rate and that everyone reacts a bit differently to a large reduction in calories but the big questions are: Is this slowdown a big reason why some people gain the weight back? How large is this slow down? …and finally, can you “reset” your metabolism with various diets for game-changing results?
The answer to the first question is now becoming clear. Three recent studies show that after substantial weight loss (over two stone), dieters did have a small reduction in metabolic rate (less than 100 calories per day) but, as they maintained most of their weight loss over the next several months and years, their metabolic rates returned to normal. Even more importantly, those who had a larger reduction in metabolic rate were not more likely to gain the weight back than those whose rates were relatively higher!
In other words, according to the latest research, metabolic rate only slows a tiny bit, even during substantial calorie reduction (a 1,000 calorie diet) and then it gradually returns to normal when a maintenance diet is adopted. It also isn’t the cause of weight regain. So, to answer the question of whether you can “reset” your metabolism? Well, this doesn’t bode well for the legitimacy of Metabolic Reset diets because they are trying to solve an insignificant problem that naturally resolves itself if the dieter adopts a proper maintenance diet after losing weight.
These studies provide strong evidence for The 1:1 Diet. All of them used the same kind of intensive calorie reduction that we use and then gradually transitioned people to eating mostly typical food, as our Plan does. So now we know what we’ve always suspected – and what several of our studies have suggested - that metabolic rate is well supported on our diet. If you want to see a few examples of people who definitely seem to have regained their metabolic rate to keep the weight off, see: Jason Blow and Cheryl Shapland!