The concept of negative-calorie food works on the theory that their thermic effect, or the calories you use to chew and digest them, is greater than the calories they contain. The process of digestion accounts for about 10 percent of the total calories your body burns for energy each day. Since losing weight is always the result of burning more calories than you eat, these negative-calorie foods can theoretically help you lose weight.
Fruits
The lower a food is in calories, the more likely it is to be catabolic, or use more of your body's energy than it contributes. The best catabolic fruits are blueberries, watermelon, grapefruit and oranges. Grapefruit also has properties that affect your insulin levels, which can help with weight loss. Blueberries are a rich source of antioxidants, as well as containing less than a calorie per berry.
Vegetables
Artichokes and bok choy are both notably low in calories. Bok choy has about 10 calories in a ½ c. serving, and a medium artichoke has about 60 calories. However, the best low-calorie vegetable is probably spinach, with only about 7 calories per cup.
Protein
High-protein foods usually have more calories than fruits and vegetables, so most are not technically catabolic; you can't possibly burn off more calories eating them than they provide. A possible exception is egg whites, at about 20 calories per egg. If you eat the whole egg, this increases to about 80 calories, however.
Tips
According to the Mayo Clinic website, your basal metabolic rate, or the number of calories your body burns while you're at rest, depends somewhat on your gender and your age. Older people burn fewer calories at rest, and men usually burn more calories at rest than women do. Between 60 percent and 75 percent of the calories you burn each day go to your basal metabolic rate. The 10 percent that your digestion burns off is over and above this, and it isn't usually susceptible to other factors that might make it vary. Although there's no definitive proof yet that negative-calorie foods work for weight loss, when you decrease your calories by consuming lower-calorie foods, you usually lose weight, especially if you also get in some exercise. Plus, negative-calorie foods include a wide range of healthy vegetables and fruits, which are good for any diet.
References
- Time Magazine: There Are No Negative-Calorie Foods; Dr. Nancy Snyderman; May 2009
- MayoClinic: Negative Calorie Foods: Diet Gimmick or Weight-Loss Aid?; Donald Hensrud, M.D.; January 2010
- The American Council on Exercise: Do Negative Calorie Foods Really Exist?; Natalie Digate Muth; June 2011
- MayoClinic: Metabolism and Weight Loss: How You Burn Calories; Mayo Clinic Staff; October 2009
- Journal of Medicinal Food: The Effects of Grapefruit on Weight and Insulin Resistance: Relationship to the Metabolic Syndrome; K Fujioka, et al.; 2006
- Medical News Today: Grapefruit and Weight Loss; January 2004
Member Comments