The
Flavor Point Diet:
The Delicious, Breakthrough Plan to Turn Off Your Hunger and Lose the
Weight
for Good
By
David L. Katz, MD, MPH,
with Catherine S. Katz, PhD
To learn how to work with
your appetite center, you must first understand it. It's time for you
and
your brain to become better acquainted.
As soon as you bite into
any food, sensory stimulation of nerve endings on the tongue leads to
the
release of a number of chemicals, including opioids, into the
bloodstream.
You release more opioids -- the body's natural versions of drugs like
morphine
-- when you consume foods high in sugar and fat, creating a powerful,
neuro-chemical
drive to overeat those foods. These opioids and other chemicals enter
the
bloodstream and carry their messages to the hypothalamus, which sends
out
yet another set of chemicals to regulate appetite. The more flavors
your
taste buds register, the more stimulated the hypothalamus becomes,
releasing
the hunger-promoting hormone neuropeptide Y. When you taste a lot of
flavors
at once, the brain releases a lot of neuropeptide Y.
Meanwhile, in response to
the smell and taste of food, your stomach produces the hormone ghrelin,
which also stimulates appetite. It continues to produce this hormone
until
you eat enough food to literally fill your stomach and stretch the
stomach
wall. Farther down the line, in your intestines, levels of several
hormones
rise to varying degrees -- depending on the nature of your meal --
either
inducing more hunger or turning off hunger.
To understand how your food
choices can influence this complex chain of events, let's take a closer
look at how this all works by comparing the neurochemical response to
two
foods you might eat for breakfast: a sausage, egg, and cheese English
muffin
sandwich and a bowl of oatmeal.
In the mouth: The mix of
sugar, fat, and salt in the egg sandwich triggers the release of more
opioids
than the oatmeal does. These opioids create a powerful, neuro-chemical
drive
to eat more sandwich.
In the brain: The sandwich's
sausage, cheese, and muffin offer many varied tastes, causing
neuropeptide
Y -- and hunger -- to surge. The simple flavors of the oatmeal result
in
the release of much less neuropeptide Y.
In the stomach: The sandwich
delivers a lot of calories in a small package. It doesn't stimulate the
stomach's stretch receptors nearly as quickly as the oatmeal, allowing
ghrelin levels to remain high long after you've overeaten. You must eat
many more egg sandwich calories than oatmeal calories before the
stomach
wall registers fullness.
In the intestines: The highly
processed sandwich bread less effectively suppresses hunger-producing
hormones
than does the oatmeal, again leaving you feeling hungry despite the
abundance
of calories.
In the bloodstream: The stomach
and intestines quickly convert the simple starch and sugar in the white
bread into glucose, or blood sugar. The glucose seeps through the
intestinal
wall and into the bloodstream, sending blood sugar levels up. In
response,
the pancreas overproduces insulin, which moves glucose from the blood
into
muscles and other tissues. The insulin quickly drives down blood sugar,
leading to more hunger.
On the other hand, the fiber
in the oatmeal dissolves in water inside the intestines, where it
creates
a barrier through which nutrients must pass to get into the
bloodstream,
thus slowing the entrance of glucose into the blood. The result is a
slower,
lower rise in blood sugar; a slower release of insulin; no rapid surge
and dip in blood sugar levels; and lasting fullness.
As you can see, what you
eat has a powerful ability to influence how much you must eat to feel
full
and satisfied. You can't think yourself thin, as some books in the past
have claimed. But by organizing the flavors in your foods, you can
manipulate
this complex series of chemicals and subdue the appetite center in your
brain sooner, before you've overeaten.
Reprinted from: The Flavor
Point Diet: The Delicious, Breakthrough Plan to Turn Off Your Hunger
and
Lose the Weight for Good by David L. Katz, MD, MPH with Catherine S.
Katz,
PhD © 2005 David L. Katz. (January 2006) Permission granted by
Rodale,
Inc.
Author
David
L. Katz, MD, MPH,
FACPM, FACP, is associate professor of public health, director of the
Yale
Prevention Research Center, and associate director of nutrition science
at the Rudd Center for Food Policy and Obesity at Yale University.
Medical
contributor for ABC News, Dr. Katz writes a monthly nutrition column
for
O: The Oprah Magazine and a health and nutrition column for the New
York
Times Syndicate. Twice honored by the Consumers' Research Council of
America
as one of America's top physicians in preventive medicine, Dr. Katz is
one of the nation's foremost authorities on nutrition, weight control,
health promotion, and the prevention of chronic disease. He lives with
his wife, collaborator Catherine S. Katz, PhD, and their five children
in Connecticut.