Metabolism in a World of Crash Diets 15/04/2020

Extreme diets can be an effective way to lose weight quickly, but what many dieters do not realize the internal damage that occurs simultaneously. What may seem like a simple calorie deficit and carbohydrate reduction can result in much more than weight loss.

The Atkins, South Beach, Zone, and most recent, Ketogenic diet may all sound different, but are strikingly similar in their guidelines. All four diets are adversized as a healthy way to lose weight fast, with one catch being lowering carbohydrate intake.

The Ketogenic diet specifies 20 grams of net carbs are permitted in one day, to allow the body to go into the ketosis phase. Ketosis occurs when the body is deprived of carbohydrates, which is the body’s main energy source, forcing the body to use stored fat and proteins as fuel. This allows your body to burn fat as fuel instead of fueling off of carbohydrates that are consumed. This phase is not unique in diet trends, but different methods of measuring carbohydrate intake are used.

Another example of a diet that measures out carbohydrates is the Zone diet, created by Dr. Sears, a biochemist. He specified that a meal should be comprised of 40% carbohydrates, 30% fats, and 30% protein. Although this may not be as extreme, it is still considered a carbohydrate deficit, as the Dietary Guidelines for Americans suggests carbohydrates should make up 45-65% of an individual's daily caloric intake.

What the average individual may not be aware of at the start of their diet that promises weight loss, is that a calorie deficit results in slowed metabolism. A slowed metabolism burns fewer calories, making weight loss through activity harder to achieve. Caloric deficit diets have been shown to be harmful to one’s health, long after a diet has been terminated. Once a metabolism is suppressed, it can be hard for the body to increase BMR, even if the body is being fueled sufficiently. Because carbohydrates are the body’s fuel, when the body is deprived, it will reach for fat and protein; meaning that not only will an individual lose weight from fat loss, but muscle weight will also diminish, ultimately weakening both the body and metabolism.

A standard diet should consist of fats, proteins, and carbs, all in moderation. Doctors, nutritionists, registered dieticians, and other health professionals should be the only individuals recommending diets to improve quality of life, not tabloid magazines.