The Volumetrics diet shows you how you can eat a lower-calorie diet that helps promote weight loss, but still eat satisfying portions of food. The concept of Volumetrics is that by eating foods that are low in calories but high in density, you can eat larger amounts of food. This diet was developed by Barbara Rolls, PhD, a professor at Penn State.

How Is This Diet Supposed to Work?

The premise of this diet is that many diets fail because they don’t satisfy or control hunger. With the volumetrics diet, however, you can eat larger portions of food. The key is minimizing the energy density of your meals, which you can do through techniques such as increasing fiber content, cutting back on sauces or sweeteners, choosing fresh foods, and so on.

What’s Involved?

Volumetrics involves eating a diet that is made up primarily of lower density foods. Energy density refers to the amount of calories per gram contained in a particular food. The following chart provides some examples of different energy density levels.

Very Low-Energy-Dense Foods

Low-Energy-dense Foods

Medium-Energy-dense Foods

High-Energy-Dense Foods

(0-0.6 calories/gram)

(0.6-1.5 calories/gram)

(1.5-4.0 calories/gram)

(4.0-9.0 calories/gram)

Load up on:

  • Chicken broth
  • Broth-based soups
  • Cucumber
  • Celery
  • Tomato
  • Milk
  • Carrots
  • Peach
  • Raspberries
  • Apples

Start monitoring portion size of:

  • Tofu
  • Yogurt (plain, low-fat)
  • Grapes
  • Vegetarian chili
  • Banana
  • Shrimp
  • Olives
  • Potatoes
  • Pasta

Control your portion size of:

  • Frozen yogurt
  • Eggs
  • Turkey breast
  • Raisins
  • Italian dressing
  • Bagel
  • Hard pretzels
  • Angel food cake
  • Sirloin steak
  • Ravioli

Limit your intake of:

  • Potato chips, baked
  • Croissant
  • Graham crackers
  • Granola bar
  • Bacon
  • Tortilla chips
  • Peanut butter
  • Ranch dressing
  • Pecans

The theory behind this diet is that by eating mostly very low-energy and low-energy dense foods you can eat large, satisfying portions. While you can still eat high-energy dense foods, you should limit how much you eat and substitute other foods when you can.

To determine how energy dense a food is, simply divide the calories by the weight in grams. For example, a food that has 50 calories per 50 grams would have an energy density of about 1, placing it in the low-energy dense category.

Strategies for lowering the energy density of a meal include:

  • Adding water-rich ingredients (eg, fruits and vegetables)
  • Incorporating high-fiber ingredients (Fiber is a form of carbohydrate that cannot be fully digested, so it does not contribute many usable calories.)
  • Reducing the amount of fat (eg, from butter, oil, meat)

In addition to eating low-energy-dense foods, here are some other ways to feel full:

  • Protein—Eating a bit of lean protein with your meals can help promote satisfaction and fullness.
  • High-fiber, whole-grain cereals—Eating high-fiber cereal at breakfast is associated with eating fewer calories at lunch.

The Volumetrics Eating Plan helps set realistic goals for losing weight and includes exercise into the plan. It also shows you how to track your progress and offers tips for overcoming behavioral challenges. For people who may have lost touch with what it feels like to be hungry or full, there are suggestions for relearning these sensations, too.

What Does the Research Say?

This diet is based on research conducted by Dr. Rolls in her lab at Penn State, as well as other credible scientific studies. These studies have shown that the total weight of food that a person consumes from one day to the next stays about the same, even if the total calories varies.

Are There Any Concerns With This Diet?

The main concern with this diet is making sure that people don’t completely give up certain healthful high-density foods, such as olive oil and nuts. Likewise, loading up on diet sodas or artificially sweetened foods—just because they are low in energy density—is not the best practice since these foods are usually low in nutrients.

Bottom Line

If you have tried other diets but never felt satisfied with the small portion sizes or limited amounts of food, then this diet may be for you. This diet offers a realistic, lifelong approach to eating that is low in calories but still satisfying.