Decreasing Consumption of Energy-Dense Foods
Research has shown that, in general, people eat a fairly consistent volume of food every day1. Since it is hard to visualize volume, think of it this way: We tend to eat roughly the same number of mouthfuls of food from day to day. So, for convenience, let’s say we usually eat approximately 100 mouthfuls of food each day. Research shows that this is true whether the food is high or low in energy (calories). So if you select foods that are low in calories but high in volume, total calorie consumption after eating 100 mouthfuls will be lower than if you selected foods that are high in calories.
Research shows that choosing low-energy-dense foods — foods low in calories but high in volume — can help people feel full without consuming a lot of calories. That is why diets of low energy density are favored for the sake of weight control. The secret is to select foods that have one (or more) of the following attributes:
- Low in fat (since fat delivers DOUBLE the calories of carbohydrates or proteins)
- High in fiber (since fiber delivers bulk or volume but no calories)
- High in water (since water adds volume but zero calories)
How do we accomplish this when choosing foods in the market?
To choose foods that offer fewer calories per mouthful, keep in mind that vegetables are naturally low in calories but high in nutritional quality as well as volume because of their high water and fiber content. So adding plenty of vegetables to your diet will add volume but few calories. The same is true for whole grains since they are naturally high in fiber, or products made from whole grains such as cereals, bread and pasta. To identify whole grain food products make sure you see the word “whole” on the ingredients listing. Better yet, learn how to make them yourself from whole grain ingredients.
Fruits are a good choice if you are looking for something sweet but low in calories. Fruits are high in volume (low in energy density) due to their high fiber and water content. But beware of dried fruit which means the water has been removed, thus concentrating the calories, i.e. raising the energy density.
For protein foods of lower energy density, look for lower fat items. Choose fish, poultry and leaner cuts of meat; or if you choose a fattier cut, trim away the visible fat. If available, grass-fed, grass-finished beef or bison or even wild-caught game are lower in fat than conventionally-raised meat.
For manufactured food products (the ones with a “Nutrition Facts” label), identifying those of lower energy density can be a bit more complicated, but the goal is to seek lower fat, high fiber food products. The Nutrition Facts label can help. Consult the Nutrition Facts to learn the weight of a serving of the food product and the calories in that serving. Energy density is the amount of energy (calories) per unit weight of that food. Energy density is expressed as “calories per gram” to allow you to compare two foods (such as two cereal products) to one another. For example one cereal has 170 calories per 55 g serving or an energy density of 3.1 calories per gram. The other cereal has 210 calories per 58 g serving or an energy density of 3.6 calories per gram, so the second cereal is higher in energy density. For dairy products, the trick is to choose lower fat varieties. So if you are currently choosing 2% milk, try choosing 1% or even skim (fat free) milk instead. The dairy industry now offers many tasty lower fat varieties that are lower in calories and therefore lower in energy density.
If carrying a calculator to the supermarket is not your style, remember that the goal here is to discourage consumption of higher calorie cakes, cookies, chips, candy, ice cream and other energy dense foods that are of low nutritional quality. These are the foods that deliver plenty of calories but few nutrients and they are easily overeaten because they of such high energy density. Choose instead lower calorie food products of lower energy density that help you feel full on fewer calories.
Low Energy Dense Diets Deliver Other Health Benefits
Generally, a low-energy-dense diet will also be low in fat, since fat contains more than twice as many calories per gram as do protein and carbohydrates. A lower fat diet is generally considered more heart-healthy because it is associated with a reduced risk of cardiovascular disease. Low-energy-dense diets also tend to be high in water and fiber content because both add volume but not calories. Diets rich in fiber may reduce the risk of cardiovascular disease and promote bowel health, and, of course, water maintains the hydration of the body which is also important for good health.
The amount of energy, or calories, that a person should consume each day to gain, lose or maintain weight varies according to age, sex, height, weight and physical activity level. Online guidance for individuals can be found the Shape Up America! CyberKitchen. When energy consumed exceeds energy expended, the result is weight gain in the form of fat. According to government data, , approximately two-thirds of the adult residents of the U.S. have a body mass index (BMI) equal to or greater than 25. For most, this means that they have taken in more calories than they have used and are storing the extra energy as fat.
1 Rolls BJ, Barnett RA Volumetrics: Feel Full on Fewer Calories. HarperTorch Publishers 2003