to the Volumetrics plan focus on eating water- and
fiber-rich foods to achieve satiety, the feeling of full-
ness after a meal.Origins
Volumetrics is based on more than two decades
of research by nutritionistBarbara Rolls, Ph.D., the
endowed Guthrie Chair in Nutrition at Pennsylvania
State University. Rolls has been president of the
Society for the Study of Ingestive Behavior and the
North American Association for the Study of Obe-
sity. She was also a member of the Advisory Council
of the National Institute of Diabetes and Digestive
and Kidney Diseases (NIH) and a member of the
National Task Force on the Prevention and Treat-
ment of Obesity. She has also been published in a
variety of peer-reviewedjournals, including theJour-
nal of the American Dietetic Association,New England
Journal of Medicine,and theAmerican Journal of
Clinical Nutrition.
In her laboratory at Penn State, Rolls has studied
dietary patterns and eating behavior. Based on her
research and that of others, she has determined that
the volume of food that people eat affects both how
satisfied they feel and how much they eat.
Scientists like Rolls who study eating behavior
have observed that over the course of a day or two, a
person eats about the same weight of food. To lose
weight, then, a person can lower the calories in each
portion of food while maintaining the same amount of
food. If a dieter eats the Volumetrics way and
increases thewaterandfibercontent in their daily
food intake, he or she will still feel full. However,
because the person is taking in fewer calories than
before, weight loss will occur.Description
According to Volumetrics, the ideal weight-loss
program has several elements.
It satisfies hunger.
It reduces calories.
It meets a person’s nutritional needs.
It includes physical activity.
In addition, a weight-loss plan should also be
enjoyable so that users feel able to sustain the healthy
eating principles long-term.
Volumetrics offers detailed guidance on nutrient
and fluid intake, as well as physical activity. In the 326-
page publication Volumetrics: Feel Full on Fewer
Calories, published in 2000, the authors make the
following weight management recommendations:Calories (Energy): Reduce usual intake by 500 to
1,000 calories per day, depending on weight-loss
goals. This practice should lead to a healthy weight
loss of 1 to 2 pounds per week.
Fat: Limit to 20 to 30% of total calories and look for
foods reduced in fat and calories.
Carbohydrates: Carbohydrates should comprise
55% or more of total calories; it’s preferable to
choose carbohydrates from whole grains, vegetables,
and fruits because they are more satiating.
Fiber: Eat at least 20 to 30 grams per day from whole
grains, fiber-rich breakfast cereals, and whole fruits
and vegetables, as opposed to fruit juices. Fiber is
key for lowering energy (calorie) density as well as
increasing overall satiety.
Sugar: Choose a diet moderate in added sugars. Rolls
suggests lowering intake of sodas and other sugary
drinks because these foods add calories without sati-
ety. Use small amounts of sugar to make low-energy,
nutritious foods tastier.
Protein: About 15% of daily calories, or 0.4 grams
per pound of body weight, should come from protein
foods. Beans, low-fat fish, poultry without skin, and
lean meats are recommended as the most satiating
choices. Adequate amounts of protein are needed to
prevent muscle loss and maintain metabolism.KEY TERMS
Constipation—Inability or difficulty passing stool.
Diverticula—Small pouch in the colon.
Diverticular disorders—Disorders that involve the
development of diverticula.
Energy density—The calories in a given portion of
food.
Hemorrhoids—Swollen and inflamed veins around
the anus or rectum.
Insoluble fiber—Fiber that cannot dissolve in water;
found in whole grains, breads, and cereals as well as
carrots, cucumbers, zucchini, and tomatoes.
Irritable bowel syndrome—A chronic colon disor-
der that involves constipation and diarrhea,
abdominal pain, and mucus in the stool.
Satiety—The feeling of fullness after a meal.
Soluble fiber—Fiber that partially dissolves in water;
found in oatmeal, nuts and seeds, beans, apples,
pears, and berries.Volumetrics