The age-old
maxim "Eat breakfast like a king, lunch like a prince and dinner like a
pauper" may in fact be the best advice to follow to prevent metabolic
syndrome, according to a new University of Alabama at Birmingham (UAB) study.
Metabolic
syndrome is characterized
by abdominal obesity, high triglycerides, insulin resistance and other
cardiovascular disease-risk factors.
The study,
published online March 30 in the International
Journal of Obesity, examined the influence exerted by the type of foods
and specific timing of intake on the development of metabolic syndrome
characteristics in mice. The UAB research revealed that mice fed a meal higher
in fat after waking had normal metabolic profiles. In contrast, mice that ate a
more carbohydrate-rich diet in the morning and consumed a high-fat meal at the
end of the day saw increased weight gain, adiposity, glucose intolerance and
other markers of the metabolic syndrome.
"Studies
have looked at the type and quantity of food intake, but nobody has undertaken
the question of whether the timing of what you eat and when you eat it
influences body weight, even though we know sleep and altered circadian rhythms
influence body weight," said the study's lead author Molly Bray, Ph.D.,
professor of epidemiology in the UAB School of Public Health.
Bray said
the research team found that fat intake at the time of waking seems to turn on
fat metabolism very efficiently and also turns on the animal's ability to
respond to different types of food later in the day. When the animals were fed
carbohydrates upon waking, carbohydrate metabolism was turned on and seemed to
stay on even when the animal was eating different kinds of food later in the
day.
"The
first meal you have appears to program your metabolism for the rest of the
day," said study senior author Martin Young, Ph.D., associate professor of
medicine in the UAB Division of Cardiovascular Disease. "This study
suggests that if you ate a carbohydrate-rich breakfast it would promote
carbohydrate utilization throughout the rest of the day, whereas, if you have a
fat-rich breakfast, you have metabolic plasticity to transfer your energy
utilization between carbohydrate and fat."
Bray and
Young said the implications of this research are important for human dietary
recommendations. Humans rarely eat a uniform diet throughout the day and need
the ability to respond to alterations in diet quality. Adjusting dietary
composition of a given meal is an important component in energy balance, and
they said their findings suggest that recommendations for weight reduction
and/or maintenance should include information about the timing of dietary
intake plus the quality and quantity of intake.
"Humans
eat a mixed diet, and our study, which we have repeated four times in animals,
seems to show that if you really want to be able to efficiently respond to
mixed meals across a day then a meal in higher fat content in the morning is a
good thing," Bray said. "Another important component of our study is
that, at the end of the day, the mice ate a low-caloric density meal, and we
think that combination is key to the health benefits
we've seen."
Bray and
Young said further research needs to test whether similar observations are made
with different types of dietary fats and carbohydrates, and it needs to be
tested in humans to see if the findings are similar between rodents and humans.
"We're
also working on a study right now to determine if these feeding regimens
adversely affect heart function," Young said.