How Does the Volumetrics Diet Work?

Overview

Dr. Barabara Rolls, Penn State nutrition professor and former president of the Obesity Society, published "The Volumetrics Eating Plan" in January 2005. This style of eating is not promoted as a "diet," but instead as principles that are used to maintain a healthy lifestyle. Weight loss is achieved through consuming fewer calories than usual through higher volumes of low-energy dense, high-nutrient dense foods. Eating a variety of nutritious foods and including small portions of favorite foods is the focus, unlike deprivation-style eating plans that restrict food choices or even whole food groups. Food choices are designed to manage hunger and encourage satiety, so the desire to overeat or snack is reduced. The book includes chapters entitled "Your Personal Weight Management Plan" and "Your Personal Eating Plan," as well as 125 recipes for all food types.

Satiety and Energy Density

Experiencing satiety, or feeling satisfied and full after eating, is integral to weight management. Satiety can be achieved through reducing fat, consuming lean protein, increasing fiber, and choosing foods with low-energy density. Energy density is the measurement of calories per gram that a food provides. High-energy density means that a small portion of food is high in calories, while low-energy density means that the same size portion is lower in calories. Therefore, choosing foods with low-energy density allows larger portions for the same calories. People tend to eat similar total amounts of food each day, so gradually incorporating more low-energy dense food reduces calorie intake without restricting portion sizes. Hunger is not increased even when fewer calories are consumed. Fat has the most energy density, at nine calories per gram, so reducing fat intake saves calories. Adding foods with a higher water content, such as fruits and vegetables, also saves calories because water is no-calorie. Incorporating high-fiber foods reduces energy density and adds "bulk" that slows the digestive process. Energy density is broken into categories 1, 2, 3, and 4. Category 1 includes very low-energy dense foods such as non-starch fruits and vegetables, skim milk and broth-based soups. Category 2 has the low-energy density options of starchy fruits and vegetables, lean meats, beans and legumes, and low-fat cereals with low-fat milk. Category 3 becomes medium-energy density, including meats, full-fat dairy products, bread, salad dressings and cake. Category 4 contains the highest energy-dense foods, including crackers, chocolate, cookies, nuts, butter and oils.

Applying the Principles

The "Personal Weight Management" chapter leads followers through a five-week process of weight-management concepts. The baseline week establishes realistic personal goals, including weight, daily caloric intake and daily activity. A food diary shows current caloric intake, energy density categories, and areas which could be improved. Eating slowly and assessing hunger and satiety on a ten-point scale reacquaints the mind and body with those feelings. Improving eating behaviors and setting specific physical activity goals are also covered in Week 0. Weeks 1 to 4 encourage followers to use the meal plans included in the back of the book. Menus should be recreated as closely as possible, but some meals can be rearranged or substituted. Self-monitoring forms of "What I ate" and "How am I doing?" are used during this time for reinforcement. Consumed meals are written down, as well as the ratio of low-energy dense foods, hunger and satiety influences, daily activity and daily personal goals. The plan continues with more flexibility after week 4. Followers will choose meals based on which fit best into their lifestyles, and they should continue using the self-monitoring forms. The self-monitoring process is crucial to maintaining losses once a goal weight is achieved. The inclusion of low-energy density foods and more mindful eating behavior become part of a sustainable healthy lifestyle.