By Carlin Flora, published on January 6, 2004 - last reviewed on September 4, 2008
There's a revolution going on. And it's not being
fought with guns and bombs but with garden-variety fruits and
Call it the "smart-food revolution." It has to do with
the growing body of research showing that everyday produce can function
medically to prevent, treat and even cure common diseases.
Many green grocery items contain goodies that can help ward off the
diseases of aging, such as cancer and heart disease, and slow down the
aging process itself. Some of them can even halt the brain deterioration
and memory loss that tends to accompany aging.
All together, the findings suggest that relatively simple diet
modifications can slow down the normal process of brain aging and memory
impairment. And delicious little blueberries may be the smartest food of
Fruits and vegetables get their bright colors courtesy of
phytonutrients, or natural plant compounds. Anthocyanin, the
phytonutrient responsible for the blueberry's deep hue, is largely
thought responsible for the fruit's protective powers. In a one-two
punch, anthocyanin acts to protect the brain in two ways—as an
antioxidant and as an anti-inflammatory agent.
A Tufts University study of more than 40 fruits and vegetables
found that blueberries contain the highest concentration of anthocyanin,
giving the fruit superior ability to clean up free radicals of oxygen.
These are highly reactive molecular fragments that, left to their own
devices, undermine normal body processes by attacking cell membranes and
the genetic material contained inside cells.
Free radicals accumulate in tissue as a result of normal metabolic
activity, exposure to toxins, and age. The damage they do is collectively
known as oxidative stress, and it is now thought to cause cancer and
other age-related diseases.
So far, most of the research on blueberries has been conducted
on rats, but the results offer clear clues as to how the fruit can help
humans. A team of scientists led by James Joseph of the Friedman School
of Nutrition Science and Policy at Tufts University has found that a diet
rich in blueberries reverses age-related declines in balance and
coordination. It also improves short-term memory and spatial learning,
even in older rats.
Joseph is also conducting studies with human subjects.
Preliminary results show that people who eat a cup of blueberries a day
perform 5 percent to 6 percent better than a control group on tests of
While the mechanism is not completely understood, the compounds in
blueberries seem to reverse, or at least slow down, the damaging effects
of aging on nerve cell function and behavior by reducing oxidative
stress. In addition, anthocyanin's anti-inflammatory properties
keep blood flowing smoothly. This not only prevents hardening of the
arteries, it provides energy for mental functions and supports a bright
At the University of Maine, Dorothea J. Klimis, associate professor
of clinical nutrition, started looking at blueberries because of her
interest in heart disease and manganese, a trace mineral found in
abundance in blueberries.
She found that blueberries have a powerful effect on arteries,
keeping them from constricting in response to stress hormones. Constricted
arteries can raise blood pressure and bring on cardiovascular disease,
the leading cause of death in the U.S.
Her studies suggest that the compounds in blueberries bolster the
bioavailability of nitric oxide, an artery relaxer. She is
measuring enzymes that aid nitric oxide to see at which point in the
chemical process blueberries intervene.
Although the research points to a compound within anthocyanin,
Klimis is not interested in singling out specific ingredients. "The
food industry is notorious for extracting things and turning them into
pills. I promote whole foods. It's probably a synergistic effect
within blueberries anyhow."
Smaller, wild blueberries, the "low-bush" variety, are
thought to be healthier than cultivated blueberries because they contain
more anthocyanin. And frozen berries are just as good as fresh
Like their first cousins the cranberries, blueberries have been
shown to suppress urinary tract infections, and to reduce eyestrain, too.
"Hippocrates said to use food as medicine," Klimis reports,
"but doctors don't do that."