An Excerpt From
The Flavor Point Diet
 By David L. Katz, MD, MPH, with Catherine S. Katz, PhD
Authors of
The Flavor Point Diet: The Delicious, Breakthrough Plan to Turn
Off Your Hunger and Lose the Weight for Good
The most important, prevalent, and
powerful reason we eat and overeat is sensory delight: We do it because we see,
smell, and taste food. You, along with every other human, have a sensory relay
system that connects your mouth to your brain, your brain to your stomach, and
your stomach back to your brain. Ultimately, your brain is in charge of your
eating behavior. It controls what you eat and what you like to eat. As soon as
you taste food, the sensory information registers in the hypothalamus in the
brain, which, depending on the flavor of the food, sends out signals to eat
more or eat less. Because of this sensory relay system, the appetite center in
your hypothalamus can become aroused -- and in some cases overly aroused -- by
how a food tastes.
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, neurochemical 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, neurochemical 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;$24.95US/$33.95CAN; 1-59486-162-5) Permission granted by Rodale, Inc.,
Emmaus,
PA
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.
For more information, please visit
www.flavorpointdiet.com. |
