Is a Calorie Really a Calorie?

There’s a huge myth in dieting that has been perpetuated by seemingly smart individuals who get christmas cards addressed to Dr. something or other. The myth is that a calorie is a calorie and calories in vs calories out is the only way to loose weight.

We believe this myth because it’s all we ever hear, sometimes from our own personal doctor. Well it isn’t true.

Since calories are really just a measure of heat energy let’s look at it this way:

  • 1 calorie of food = 4.1868 kilojoules
  • 195 lb male requires about 2000 calories a day or 60,000 calories per month
  • 1 gallon of gas = 131,760 kilojoules or 31,470.3 calories

So simply assuming calories are units of energy that our body burns or stores and disregarding the type or quantity of these nutrients I could power my body  on about 2 gallons of 93 octane gas…I’ll take E85 please.

Ridiculous, eh?

Not if you believe calories in calories out and a calorie is a calorie.

In the July 1956 edition of The Lancet Doctors Kekwick and Pawan, compared three groups put on semistarvation diets consisting of 90% fat, 90% protein, or 90% carbohydrate. Here were the outcomes:

  • 1,000 cals. at 90% fat = weight loss of 0.9 lbs. per day
  • 1,000 cals. at 90% protein = weight loss of 0.6 lbs. per day
  • 1,000 cals. at 90% carbohydrate = weight gain of 0.24 lbs. per day

Different sources of calories = different results.