Each attempt at this approach results in further reduction of the BMR with worsening of the metabolic adaptation to energy deficiency.
At PHD we have listened to thousands of clients tell us about their struggles with weight loss and maintenance prior to starting on the PHD program and ultimately finding success. Almost universally these struggles have included an attempt at calorie counting, food restriction and exercise. The idea that limiting intake and increasing output is the simple indisputable way to lose weight and keep it off has been told and retold so many times that it has been socially accepted as truth without any real scientific evidence. Clients will sometimes point to the success of the contestants on The Biggest Loser as clear proof of concept. And yes! These contestants do lose weight using this approach and my guess is you have too. However, research shows that this approach results in weight loss plateaus and weight regain. Why? The research can help us figure this one out.
First, we must understand two clinical terms, Basal Metabolic Rate or BMR and metabolic adaptation. BMR also sometimes referred to as RMR (resting metabolic rate) or REE (resting energy expenditure) is the energy needed to perform all basic bodily functions and makes up most of the calories required throughout the day. This rate of energy consumption can be increased or decreased by hormonal control of the body based off of need and availability of energy(calories). So, when someone reduces intake of available energy with severe calorie restriction the body responds by slowing down or shutting down bodily functions in order to lower the BMR. That’s why calorie restriction eventually result in weight loss plateaus. The BMR has lowered enough to balance the consumed energy.
There is some thought that attempting to maintain lean muscle with exercise while dieting will minimize this effect. While it is possible to minimize lean muscle loss with exercise for those that lose considerable weight some loss of lean muscle mass is expected and healthy. As the body loses some of this muscle your BMR will reduce some but research demonstrates a phenomenon called Metabolic Adaptation (MA) also known as Adaptive Thermogenesis (AT). This measures the decrease in BMR over what you would expect from the decrease in lean muscle mass. As BMR lowers and metabolic adaptation to energy deficiency gets larger weight loss efforts get harder. For successful weight loss to continue one would have to lower their calorie consumption even more, but this will lead to a subsequent plateau, further lowering of the BMR with an even larger metabolic adaption. Eventually dieters get frustrated and increase their calorie consumption.
Unfortunately, the BMR will not increase with increases in nutrient consumption which is why people using this approach frequently gain more weight than they started with and find it even harder to be successful the next time. This yo-yo effect results in a very low BMR and a damaged metabolism as measured by metabolic adaptation. Unfortunately, this also leads to incredible frustration and feelings of failure! If you find it hard to believe that this could be true look at the following studies on The Biggest Loser contestants.
This study published in 2012 on 12 of the 16 contestants from The Biggest Loser reported how significant the reduction of BMR was for the 30 week intensive program. The group started with an average weight of almost 330 pounds and lost nearly 130 pounds on average. The BMR however also declined almost 800 calories or 30% on average. The greatest drop in BMR was over 1000 calories! The metabolic adaptation to this effort was nearly 500 calories with the greatest measure of over 700. Meaning that the BMR was 700 calories less for that participant than would be expected based off of lean body mass. What does that mean for weight maintenance?
In this follow up study on 14 of the 16 participants they looked at maintenance of weight as well as response of the reduced BMR and MA over time to determine if their success was maintained after the show.
Six years after the intensive program, all but one contestant gained most of their weight back.
5 of the 14 were at or above where they started. The average weight loss from baseline went from 130 pounds down to less than 40. Shockingly the average BMR DID NOT return to normal and in fact continued to decrease 6 years after the show despite weight regain. Metabolic adaptation also continued to increase demonstrating worsening metabolic adaptation to a low energy state as demonstrated in Dr. Ashley Lucas’ doctoral thesis on this topic.
Sadly, this is a typical story for so many of our clients before they see success with PHD. Weight regain from calorie restriction is frequently met with feelings of failure and despair. So many people feel that there must be something wrong with them if they can’t succeed with such a simple approach that is so well “known” as the truth to successful weight loss. The research above indicates that it is not your fault, it’s the approach. Simple calorie restriction is a recipe for failure for nearly everyone. Each attempt at this approach results in further reduction of the BMR with worsening of the metabolic adaptation to energy deficiency. This is part of the metabolic damage that makes each attempt at further weight loss more difficult and maintenance more challenging. Enter into successful weight loss without causing metabolic damage by utilizing a different approach- An approach designed for successful fat loss and weight maintenance.