Researchers Look at How Frequency of Meals May Affect
By Rosalie Marion
February 15, 2008
The health consequences of eating
one large meal a day compared with eating three meals a day has not been
established. Now two recently published journal articles are among the first to
report the effects of meal skipping on key health outcomes, based on a study
involving a group of normal-weight, middle-aged adults.
The study analyses were authored by scientists at the Agricultural Research
Human Nutrition Research Center in Beltsville, Md., and colleagues at the
National Institute on Aging (NIA)
Intramural Research Program in
For the study, a small group of male and female volunteers participated in
two eight-week meal-treatment periods. The study's crossover design meant that
each volunteer completed both of the treatment diets, enabling them to serve as
their own controls.
Volunteers were divided into one of two groups during each treatment period.
They consumed either all of their required weight-maintenance calories in one
meal a day or in three meals a day. ARS physiologists
Rumpler and NIA neuroscientist Mark Mattson designed the study.
The first study analysis showed that consuming a one-meal-per-day diet,
rather than a traditional three-meal-per-day diet, is feasible for a short
duration. It showed that when the volunteers were "one-mealers," they
had significant increases in total cholesterol, LDL "bad" cholesterol
and in blood pressure, compared to when they were "three-mealers."
The changes in cardiovascular disease risk factors occurred despite the fact
that the one- mealers saw slight decreases in their weight and fat mass in
comparison to when they were three-mealers. Those findings were published in
the April 2007 issue of the American Journal
of Clinical Nutrition.
Further analysis of the study group showed that when the volunteers were
one-mealers, they had higher morning fasting blood sugar levels, higher and
more sustained elevations in blood sugar concentrations, and a delayed response
to the body's insulin, compared to when they were "three-mealers."
Insulin is required to lower blood sugar levels. Those findings were published
in the December 2007 issue of Metabolism.
ARS is the U.S. Department of
Agriculture's chief scientific research agency.