Energy Density

Cutting Calories: Portion Control, Energy Density

Article By: The Weight Watchers Research Dept. Print Email

DECEMBER 2006—Two credible weight-loss methods to reduce calories in a way that meets overall nutritional needs are portion control and energy density.

In order to lose weight, energy balance must be put into the red zone. In other words, you must: Eat fewer calories than your body needs to maintain its current weight; Increase the calories burned in physical activity, or Do a combination of the two.

Credible weight-loss methods are designed to reduce calories from food in a way that meets overall nutritional needs. Two approaches with a proven track record for weight management are portion control¹ and energy density.²

Portion Control
Portion control works by specifying the amount, or portion size, of foods eaten in a day with the goal of eating a specific number of calories. Weight-loss plans that work on portion control are characterized by "counting" foods eaten by serving or following a very specific meal plan. Examples of diets that are based on portion control include the diabetic exchange diet, the USDA Food Guide Pyramid and most "7-day diets" in women's magazines.

Energy Density
Energy density works by focusing choices on foods that provide a good volume-for-calories ratio. Low energy density foods tend to be rich in water and fiber and low in fat. Examples include soups, stews, vegetables, and fruits. Weight-loss plans that work on energy density concentrate on what foods are eaten instead of how much (e.g., "start every lunch and dinner with a broth-based soup or green salad" or "eat whole grains").

Emerging research suggests that energy density and portion control are independent factors for weight loss.³ This finding suggests that weight-loss plans that combine elements from each approach may lead to a greater weight loss than either used alone.

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The Weight Watchers Approach: The Flex Plan is primarily a portion-controlled approach to reducing calories. Lower energy density foods are encouraged because the POINTS® formula includes dietary fiber and total fat as well as calories to calculate the POINTS value per serving of food. The Core Plan is primarily an energy density approach to reducing calories. The Core Food List includes only foods with a low energy density and portions are adjusted based on an individual's determination of when she is hungry and when she is satisfied, which is known as the Comfort Zone.

RELATED INFORMATION

Other Science Library Topics:

• Macronutrient Recommendations
• Introduction to the Glycemic Index
• Glycemic Index and Weight Loss

FOOTNOTES

¹Hannum SM, Carson L, Evans EM, Canene KA, Petr EL, Bui L, Erdman JW Jr. Use of portion-controlled entrees enhances weight loss in women. Obes Res. 2004 Mar;12(3):538-46.

²Drewnowski A. The role of energy density. Lipids. 2003 Feb;38(2):109-15

³Kral TV, Rolls BJ. Energy density and portion size: their independent and combined effects on energy intake. Physiol Behav. 2004 Aug;82(1):131-8.