Editor's Note:  The Negative Calorie Diet works, but as you'll find out in today's article, it isn't necessarily the smartest diet for long-term success.

The Negative Calorie Diet will help you lose weight. You might - as the book promises - lose 14 pounds in 7 days. However, the diet is not one that I use or recommend. Let me explain why.

The Negative Calorie Diet is based on the idea that some foods cause you to burn more calories digesting these foods than the actual calorie content of the food itself.

It's true that some foods raise your metabolic rate more than others do. Carbohydrate and protein, for example, contain about four calories per gram. But, the thermic effect of protein is far greater than that of carbohydrate.

In other words, some of the energy in each gram of protein is wasted as heat during the process of digestion and metabolism. The thermic effect of nutrients is approximately 2–3 % for fat, 6–8 % for carbohydrates, and 25–30% for proteins [2].

The foods you eat on The Negative Calorie Diet are mainly fruit and vegetables. For breakfast, you might have a bowl of strawberries or an orange. A snack might consist of apples or celery. You can have soup for lunch and dinner, though foods like chicken or fish are allowed after the first few days.

The reason that fruit and vegetables help you lose weight is not because they're "negative calorie foods."

Rather, fruit and vegetables have a very low energy density. Energy density refers to the number of calories in a gram of food. If you check the nutrition label on the top of a food label, you should find the standard serving size of the food, and the number of calories in that serving.

To calculate the energy density, divide the calories by the weight. A food that contains 200 calories and weighs 100 grams, for example, has an energy density of 2.0.

Let’s use grapes and raisins (which are nothing more than dried grapes) as an example. If you wanted to eat 150 calories of raisins, you’d be able to eat approximately 50 grams. Yet the same number of calories would give you almost 220 grams of grapes - more than four times as much.

Because the grapes are higher in volume, they’ll keep you feeling fuller for longer, and you’ll eat less over the course of the day.

Editor's Note: Jon Benson, a fitness expert and lifecoach, wrote an excellent article about the importance of the energy density of foods to lose fat and get fit. The article is titled, Can The Weight Of Your Food Affect The Weight Of Your Body?

In one eating study at Pennsylvania State University, a group of women hardly noticed when they ate fewer calories each day - as long as their meals contained lots of fruits and vegetables to bulk up the servings and lower the energy density [1].

The Bottom Line

You will lose weight on the Negative Calorie Diet. You might - as the book promises - lose 14 pounds in 7 days. But 14 pounds of what? A lot of it will be muscle and water, and not fat.

More information on how to burn fat without losing muscle is available in the Members-Only Area of my website, TheFactsAboutFitness.com. Tom Venuto also covers the same subject in his excellent e-book, Burn the Fat Feed the Muscle.

As soon as people hear the word "diet," they think of restriction, and pain. However, the word comes from the Latin term diatea, which means "a way of living."

Follow any diet to the letter, and you'll probably lose weight. But, if it isn't a way of eating you can live with for more than two weeks, you'll have to come off it again.

Don't be deceived by false promises. When something sounds too good to be true, it usually is.

Read other articles by Christian Finn

About the Author

Christian Finn is a Certified Personal Trainer and holds a masters degree with distinction in exercise science. He's lectured at a number of universities and private training organizations around the United Kingdom on fitness training, weight loss and the effective use of nutritional supplements. He writes extensively on the subject and his articles have been published in numerous magazines, leading industry journals and websites worldwide, including Men's Health, Men's Health Muscle, Fit Pro (April/May 2001), CAM magazine (February 2003), Image (January 1997), Zest (March 2004), and Body Life magazine (March/April 1997). He was also featured in the July 2004 issue of Muscle & Fitness (UK edition). His website, TheFactsAboutFitness.com, is dedicated to providing its members up-to-date, unbiased information and research on the world of fitness.

References

1. Bell, E.A., Castellanos, V.H., Pelkman, C.L., Thorwart, M.L., & Rolls, B.J. (1998). Energy density of foods affects energy intake in normal-weight women. American Journal of Clinical Nutrition, 67, 412-420

2. Jequier, E. (2002). Pathways to obesity. International Journal of Obesity and Related Metabolic Disorders, 26, S12-S17