(MayoClinic.com) Feel full on fewer calories? It might sound like another gimmick for weight loss, but it's not. Rather, it's putting the concept of energy density into practice to help with your weight loss. In fact, well planned weight-loss diets, such as The Mayo Clinic Diet, use the concept of energy density to help you lose weight and keep it off long term.
Weight loss with more food, fewer calories
Simply put, energy density is the number of calories (energy) in a specific amount of food. High energy density means that there are a lot of calories in a little food. Low energy density means there are few calories in a lot of food.
When you're striving for weight loss, the goal is to eat low-energy-dense foods. That is, you want to eat a greater volume of food that's lower in calories. This helps you feel fuller on fewer calories. Here's a quick example with raisins and grapes. Raisins have a high energy density — 1 cup of raisins has about 434 calories. Grapes have a low energy density — 1 cup of grapes has about 104 calories.
The keys to energy density and weight loss
Three main factors play a role in what makes food high or low in energy density:
Energy density and the food pyramid
- Water. Many fruits and vegetables are high in water content, which provides volume and weight but not calories. That's why they're low-energy-dense foods. Grapefruit, for example, is about 90 percent water. Half a grapefruit has just 39 calories. Raw, fresh carrots are about 88 percent water. Half a cup has only about 25 calories.
- Fiber. High-fiber foods not only provide volume, but also take longer to digest, making you feel full longer on fewer calories. Classic examples are vegetables, fruits and whole grains.
- Fat. Fat is high in energy density. One teaspoon of butter, for example, contains almost the same number of calories as 2 cups of low-energy-dense raw broccoli. Most fruits and vegetables don't contain a lot of fat. Foods that contain fat naturally, such as dairy products and various meats, or foods with added fats are higher in calories than their leaner or lower fat counterparts.
Changing lifestyle habits is never easy, and creating an eating plan using the energy-density concept is no exception. The first step is knowing which foods are better options when it comes to energy density. Here's a look at energy density by the categories in the Mayo Clinic Healthy Weight Pyramid.
Making energy density work for you
- Vegetables. Most vegetables are low in calories but high in volume. Examples include — salad greens, asparagus, green beans, broccoli and zucchini. To add more vegetables to your diet, top your pasta with sauteed vegetables instead of meaty or cheesy sauces. Decrease the meat portion on your plate and increase the serving of vegetables. Add vegetables to your sandwiches. Snack on raw vegetables.
- Fruits. Practically all types of fruit fit into a healthy diet. But some fruits are lower calorie choices than others are. Whole fresh, frozen and canned fruits without added sugar are good options. In contrast, fruit juices and dried fruits are concentrated sources of natural sugar and therefore have a high energy density — more calories — and they don't fill you up as much. To fit more fruits into your diet, add blueberries to your cereal in the morning. Try mango or peach slices on whole-wheat toast with a little peanut butter and honey. Or toss some mandarin orange and peach slices into a salad.
- Carbohydrates. Many carbohydrates are either grains or made from grains, such as cereal, rice, bread and pasta. Whole grains are the best option because they're higher in fiber and other important nutrients. To include more whole grains in your diet, simply choose whole-wheat bread, whole-wheat pasta, oatmeal, brown rice and whole-grain cereal instead of refined grains.
- Protein and dairy. These include food from both plant and animal sources. The healthiest low-energy-dense choices are foods that are high in protein but low in fat and calories, such as legumes (beans, peas and lentils, which are also good sources of fiber), fish, skinless white-meat poultry, fat-free dairy products and egg whites.
- Fats. While fats are high-energy-dense foods, some fats are healthier than others. Include small amounts of healthy monounsaturated and polyunsaturated fats in your diet. Nuts, seeds, flax oil, and vegetable oils, such as olive and safflower oils, contain healthy fats.
- Sweets. Like fats, sweets are typically high in energy density. Good options for sweets include ones that are low in added fat and that contain healthy ingredients, such as fruits, whole grains and low-fat dairy. Examples include fresh fruit topped with low-fat yogurt, a cookie made with whole-wheat flour or a scoop of low-fat ice cream. The keys to sweets are to keep the serving size small and the ingredients healthy — even a piece of dark chocolate fits.
When you stick to the concept of energy density, you don't have to feel hungry or deprived. By including plenty of fresh fruits and vegetables and whole grains in your diet, you can feel full on fewer calories. You may even have room in your diet for a tasty sweet on occasion. By eating larger portions of low-energy-density foods, you squelch those hunger pains, take in fewer calories and feel better about your meal, which contributes to how satisfied you feel overall.
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