Since 1958, we have been measuring pounds lost by the simple rule “One pound equals 3500 calories.” Better stated, to gain one pound or, for most of us, to lose one pound, we need to have a calorie deficit of 3500 calories. In the American journal of Clinical Nutrition, Dr. Max Washnofsky stated the math is straight forward. If you can cut or burn 500 calories per day, which seems easy to do, in one week (7 days) you will lose 1 pound.
So, if I just workout a few times a week and cut the red wine or potato chips out of my current routine I will be down 10 lbs in no time? Right?
Wrong. There is a pretty big flaw in this thinking. For those of us who have tried this method, we can attest that the “500-calorie-rule” assumes weight loss will continue in a linear fashion over time. Unfortunately, this is not the way most bodies respond.
Metabolic Adaptation
The culprit is Metabolic Adaptation. There are a ton of articles out there (and more on this site as well) that delve into this concept much deeper. But here is the basic premise:
In times of feast, our body can store excess calories, mostly in fat, for future use. However, in times of “famine” aka weight lost either by increased exercise and “diet” or decreased food intake, the body does interesting things!
- Burns less calories at a cellular level to produce the same energy because the body thinks it needs to hold on to the calories for basic survival
- Decreased energy and ultimately performance which equals less calorie lost for the same activity prior to the deficit
- Elevations in hormones that promote catabolism (break down in metabolism used for creation of energy which may lead to muscle breakdown) increasing the feeling of hunger
- Decreased hormones that promote anabolism (breakdown in metabolism that expends energy), and the feeling of satiety or fullness.
As you can imagine, these adaptations of the body will slow down weight loss. Therefore, just because you have a 3500 calorie deficit, you may not lose 1 pound. In fact, So abandon the process altogether? No!
There is Help
There are scientific ways to calculate and predict accurate weight loss based on your personal weights and measurements. There are many national institutes and health and wellness companies that have created accurate weight loss calculators and are free online.