How dieting destroyed my Basal Metabolic Rate (BMR), and contributed to my weight loss stall, or plateau.
My next question was; why am I eating the same foods I was in beginning of my diet, but not losing weight now? Did something happen to my metabolism, did it slow down, and if so, why?
BMR: Quick facts.
The basal metabolic rate (BMR) is the rate at which your body consumes calories for basic metabolic functions at rest. Including:
- Internal temperature
- Repairing cells
- Pumping blood
- Other functions
BMR doesn’t take into account exercise or calories burned through other activities. Your BMR’s affected by the amount of muscle mass you have. The more muscle fiber, the higher your Body Mass Index (BMI) will be. Muscle, even at rest, burns more calories than fat and other tissues.
Note: This is why strength training is so important, the more muscle you have, the higher your BMI, and the higher your BMR is going to be.
You can use this calculator to calculate your own BMR. Calculator.
One of the reasons for my stall had to do with the reduction of my BMR and my decrease body mass (BMI), as I went from 260 lbs to 190 lbs. My BMR had slowed from 2,300, to approximately 1,800 calories a day. This was the same amount of calories I was eating when I started Atkins, and the same amount I was eating when I hit my weight loss plateau. Since my BMR had slowed, and I didn’t adjust my calorie consumption, I had no weight loss.
This would have been true, if not for the fact that I was active; therefore, on top of my 1,800 calorie BMR, I was burning an additional 1000 calories from other activities, which should have resulted in a 2 lb loss a week. This wasn’t happening, so something had to have screwed up my metabolism. But what? And what happened to those 1,000 calories I should have been burning? Did I go into starvation mode, reach a set point, or, did something else happen? Or perhaps it was a combination of things?
To understand these questions I had to understand what a metabolism does.
Metabolism is the amount of energy (calories) your body burns to maintain itself. Whether you are eating, drinking, sleeping, cleaning etc, your body is constantly burning calories to keep you going. It’s affected by your body composition, and the amount of muscle you have versus the amount of fat. Muscle uses more calories to maintain itself than fat. People who are more muscular, (and have a lower percentage of body fat), have a higher metabolism than those who are less muscular. For example, let’s say you have two people who are the exact same height and weight. One exercises on a regular basis with weights, and has a low percentage of body fat. The other never exercises, and has a higher percentage of body fat. The first person who exercises will have a higher metabolism than the second person will, because the extra muscle will burn more energy. If you want to have a higher metabolism, you have to have a higher body mass, or, increase your activity level. But we don’t want that mass to be fat. Ideally, we would add more muscle. The problem with dieting, and this is on any diet you are on, you lose muscle mass. It is true that you don’t lose as much muscle mass on Atkins, but you will lose some nonetheless.
So, to answer the question, did something happen to my metabolism, did it slow down, and if so why? The answer is clear; the very act of losing weight destroyed my metabolism. Not only had I lost mass due to fat loss, but also, I had decreased my BMI due to my loss of muscle.
Note: Maybe destroyed is not the right word, and I think it’s worth noting that the slowing down of a metabolism is quite normal when we lose weight. Since we are no longer carrying around all those extra pounds we don’t need as much muscle. Therefore, to conserve energy the body jettisons some of that muscle. The real problems happen when we lose more muscle than we should by dieting badly, trying to lose to quick, or by eating too little.
I’ll explain latter how to avoid this.
It was at this point the picture was starting to become clearer, but this was only part of the puzzle, there were other contributing factors to my weight loss stall. I knew I had engaged in some self-sabotaging behaviors, and so I asked myself why. My research led me to understanding the mechanism of hunger, and the role it plays in controlling our weight, and eventually to understanding set points and starvation mode. Both of which, as I would find, screwed up my hunger mechanism, and eventually led to my stall.
This is where I will pick up in part Chapter 4.