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Summary: Eating apples
may help fight the cognitive
decline associated with
aging and neurodegenerative
diseases like Alzheimer's
and Parkinson's.
 An
apple a day keeps the doctor
away, as the saying goes.
And not just any doctor. An
apple a day may help keep
the neurologist away-along
with the cognitive decline
that often accompanies aging
and neurodegenerative
diseases like Alzheimer's
and Parkinson's.
Food scientist Chang Y. Lee
recently found that a
nutrient in apples can
protect rat brain cells from
damage. The nutrient, an
antioxidant called quercetin,
provided even more
protection than Vitamin C,
which is known to combat
neurodegenerative diseases
in humans.
Quercetin belongs to a group
of substances getting a lot
of attention these days-flavonoids.
These are naturally
occurring chemical compounds
that help give plants their
color. Most flavonoids, as
well as certain vitamins and
minerals, are potent
antioxidants; they
neutralize harmful free
radicals of oxygen, produced
when cells burn oxygen for
energy. If left unchecked,
free radicals cause
cumulative cell damage that
may lead to cancer or, in
the case of brain cells,
Alzheimer's, Parkinson's or
other age-related mental
decline.
"Quercetin has much higher
antioxidant activity
compared to other flavonoids
and Vitamin C," says Lee.
His work has shown that not
only may quercetin help
brain cells, but also it may
actually hurt cancer cells.
In his lab experiments,
quercetin blocked some of
the pathways by which tumors
grow out of control, and
once again, in this task
quercetin outperformed
Vitamin C.
 Apples
are a primary source of
quercetin. The same
flavonoid is also found in
onions, tea, blueberries and
cranberries.
Other research suggests that
quercetin may have a variety
of benefits in combination
with other nutrients. A
Dutch study found that a
high intake of black tea,
which contains a variety of
flavonoids in addition to
quercetin, reduces the risk
of heart disease, and a
Finnish study found that
people who ate the most
whole apples had a lower
risk of stroke than those
who ate the least.
Substances that protect the
heart and its circulation
generally protect the brain
as well. The common
denominator is the network
of blood vessels so crucial
to both organs. Damage to
blood vessels in the brain
may impair the communication
lines between nerve cells
that underlie all mental
activity.
Lee can't say for sure yet
whether quercetin can halt
neurodegeneration in people.
Clinical trials or studies
of large populations are
needed to see whether his
lab results hold up in the
real world.
In the meantime, though, Lee
heartily recommends apples
for everyone. Given the
potential benefits of
quercetin, plus the other
nutritious qualities of
apples, he suggests that
people add an apple to the
mix of fruits and vegetables
that they eat each day.
"One apple a day provides a
significant amount of
quercetin and flavonoids,"
he notes. The exact quantity
of quercetin in an apple
varies depending on the
year, season and region the
apple was grown in. But all
apples-from red delicious to
fuji-have a large amount.
 Choose
a fresh apple over
applesauce or apple juice
for a snack, Lee suggests,
since quercetin resides
primarily in the skin of the
fruit. "Processed food may
always have a chance to lose
active compounds," he adds.
He also warns against
supplements, because large
doses of purified quercetin
may prove dangerous. And it
may turn out that quercetin
works best just as nature
intended it to be
consumed-in concert with
other substances in whole
foods.
Although Lee has devoted the
past 20 years to studying
apples, he admits that
quercetin also shows up in
blueberries, cranberries and
onions. "But how much onion
can you eat per day?" he
asks.
Article courtesy of
www.psychologytoday.com
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