Eat
your procyanidins
(continued)
In general,
plant foods are thought to play two powerful roles as anti-carcinogens.
First, they help neutralize free radicals. To generate energy, millions
of chemical reactions within the body must take place. During these
reactions, some of the electrons get moved into strange, unstable
configurations. These unpaired electrons are called free radicals.
Free radicals are a byproduct of metabolism and have the ability
to oxidize neighboring cells and create abnormal changes by attaching
to genetic material (DNA).
Defining the
"somehow" is what drives his research.
Phytochemicals
in fruits and vegetables attach to free radicals, taking away the
ability of these unstable molecules to affect surrounding cells.
Secondly, they induce enzymes in the body that repair damaged cells
and make toxins water-soluble so that they can be excreted in urine.
Fruits and
vegetables are loaded with compounds that do both - compounds like
flavonoids. Flavonoids serve many roles in plants. Some, like the
bitter tannins found in tea and wine, repel insects. Others put
the colorful hue in fresh produce. "Eat your colors - that's
pretty good advice for a healthy diet," said Mitchell.
Mitchell is
interested in procyanidins, a flavonoid found in all kinds of common
foods: grapes, barley, green tea, peaches, apples, red wine, berries,
even cocoa. Procyanidins make your body produce enzymes called glutathione
S-transferases (GSTs). GSTs are part of a family of protective molecules
known as phase 2 enzymes. These little worker cells mop up free
radicals and otherwise do all the heavy lifting of detoxifying molecules
before they can cause DNA damage.
"Glutathione
S-transferases are ubiquitous - your body makes them in virtually
every cell," said Mitchell. "But more is definitely better.
They are the most important defense system we have to protecting
against chemical carcinogens. And they can't be replicated in pills."
Home |
Table of Contents |
To our Readers |
Building on Basics
Focusing on Patients |
In Translation |
First Steps
Campus Connection |
Benefactors |
News in Brief
UC Davis Health System |
© 2000, 2001, 2002 UC Regents. All rights reserved.
|