According to the June 2007 issue of Consumer Reports, in a study
rating the diets, Volumetrics is the best carefully researched diet plan.
Volumetrics is based on eating foods with low "energy density"--that is, foods
with relatively few calories per portion and high water content (fruits, salads,
Her best-selling book is titled: The Volumetrics Eating Plan. Part
weight-control program, part cookbook, it's an effort to put into practical
form a lifetime of study on why people eat what they do and how to satisfy the
human biological drive for abundant food while achieving a healthy weight.
University's Laboratory for the Study of Human Ingestive Behavior is one of the
world's most sophisticated centers for the study of what and how humans eat. The
queen of this empire is Barbara Rolls, professor and Guthrie
chair in nutrition at the university. For nearly three decades, Rolls, 60, has
researched food choices, portion sizes, the caloric or energy density of foods,
and myriad other factors that influence the human appetite and what satisfies it.
Most recently, the lab has been
studying the impact of energy or calorie density--that is, the number of
calories in a given weight of food--on satiety and weight control. Rolls calls
this research "Volumetrics."
How The Plan Works
The Volumetrics diet program is based on eating
foods with low "energy density"--that is, foods with relatively few calories per
portion and a high water content. No foods are "forbidden".
It was Rolls who realized that
satiety, or the sensation of fullness, is "food specific." That is, when people
are full of one food, they can still eat another--an explanation, says Rolls,
"for why you always have room for dessert." She was among the first to notice
that humans eat about the same weight or volume of food every day but not the
same calories, a notion now accepted by nutrition scientists.
Yet she also discovered an
apparent contradiction: When food portions are "supersized," people eat more.
Adults offered four different portions of macaroni and cheese at her lab ate 30% more calories when given the largest portion, compared with the
smallest. Fewer than half noticed any difference in the serving sizes. Likewise,
in Rolls's sandwich experiments, men and women were served 6-, 8-, 10-, and
12-inch submarine sandwiches. When given the 12-inch sub, women ate 31% more
calories and men 56% more--compared with those given the 6-inch sub.
Asked to rate their fullness after lunch, diners reported
little difference whether they had eaten the larger or smaller sub. In a 2-day
study, portion sizes were increased for some dishes by as much as 100%, and
people continued to eat more over both days. "As to why...