Health
Benefits
New Research
Ethnobotany
Bibliography
Nutrition Summary Learning
Center
Blueberry
Health
Benefits::
From research labs all across the country and the
world, there is growing evidence that blueberries
could be powerful little disease fighters. Here
is what we have learned so far. (summary)
Antioxidants
Anti-Aging
Disease Prevention
Urinary Tract Infections
Eyesight
Antioxidants:
Researchers at the USDA Human Nutrition Center (HNRCA)
have found that blueberries rank #1 in antioxidant
activity when compared to 40 other fresh fruits and
vegetables. Antioxidants help neutralize harmful
by-products of metabolism called "free radicals" that
can lead to cancer and other age related diseases.
Anthocyanin -- the pigment that makes the blueberries
blue -- is thought to be responsible for this major
health benefit. (reference)
More on antioxidants: (antioxidants)
Anti-Aging:
In another USDA Human Nutrition Center (HNRCA) lab,
neuroscientists discovered that feeding blueberries
to laboratory rats slowed age-related loss in their
mental capacity, a finding that has important implications
for humans. Again, the high antioxidant activity
of blueberries played a role. (reference)
Disease
Prevention -
Blueberries may reduce the build up of so called "bad"
cholesterol that contributes to cardiovascular disease
and stroke, according to scientists at the University
of California at Davis. Antioxidants are believed
to be the active component. (reference)
Prevention
of Urinary
Tract Infections: Researchers at
Rutgers University in New Jersey have identified a
compound in blueberries that promotes urinary tract
health and reduces the risk of infection. It
appears to work by preventing bacteria from adhering
to the cells that line the walls of the urinary tract.
(reference)
Blueberries
and Eyesight:
A number of studies in Europe
have documented the relationship between bilberries,
the European cousin of blueberries and improved eyesight.
This is thought to occur because of the anthocyanin
in the blue pigment which is also available in the
blueberry. One study in Japan documented that
blueberries helped ease eye fatigue.
New
Research:
Around the world, blueberries are being studied in
health and medicinal studies.
Learning
Centre:
|
Eating
blueberries may help you remember where you placed
your car keys—important findings if you’d like
to keep Alzheimer’s and heart disease at bay.
The
research was presented Monday, August 19, at
the ACS national meeting in Boston.
In
one study, Jim Joseph, director of the neuroscience
laboratory in the USDA Human Nutrition Center
(HNRCA), fed blueberry extractions—the equivalent
of a human eating one cup of blueberries a day—to
mice and then ran them through a series of motor
skills tests.
He
found that the blueberry-fed mice performed
better than their control group counterparts
in motor behavioral learning and memory, and
he noticed an increase in exploratory behavior.
When he examined their brains, he found a marked
decrease in oxidative stress in two regions
of the brain and better retention of signal-transmitting
neurons compared with the control mice.
The
chemical that appears responsible for this neuron
protection, anthocyanin also gives blueberries
their color and might be the key component of
the blueberry’s antioxidant and anti-inflammatory
properties. Blueberries, along with other colorful
fruits and vegetables, test high in their ability
to subdue oxygen free radicals. These oxygen
radicals, which can damage cell membranes and
DNA through a process known as oxidative stress,
are blamed for many of the dysfunctions and
diseases associated with aging.
These
findings could become increasingly important
as the U.S. population ages. It is projected
that by 2050, more than 30% of Americans will
be over 65 and will have the decreased cognitive
and motor function that accompanies advanced
age. Joseph is currently testing the effects
of blueberries on humans. Preliminary results
show that people who ate a cup of blueberries
a day have performed 5–6% better on motor skills
tests than the control group.
|
Ethnobotany
and Blueberries: Blueberries
have been associated with positive physiological and
cosmetic benefits for centuries. Here we list
non scientific information which although not endorsed
by the USHBC, may be of interest to researchers as
a direction for further research.
|
Blueberry
Health and Nutrition traditions in China.
|
|
Native
American and First Nations of Canada blueberry
health and medicinal traditions.
|
|
Blueberry
health and nutrition in Russia and Central European
Traditions.
|
Bibliography:
Prior,
RL, et. al. J of Agric. Food Chem. 1998, 46:2686-2693
Bickford,
P.C. et. al. Society for Neuroscience Abs. 1998,
24: 2157
Heinenen,
L.M. et al. J. Agric. Food Chem. 1998, 46:4107-4112
Howell,
A.B. and V. Nicholi. New Engl. J. Med 1998, 339: 1085-1086
Nutrition
Summary: The
following summarizes some of the published research
in the area of nutraceuticals and health.
The belief
that food products have medicinal properties has been
celebrated in folk medicine for centuries. Today food
properties are being explored by the medical and scientific
fields. Some cultures have long valued many naturally
occurring substances believed to have preventative
and therapeutic value. In the United States, nutraceuticals
are part of a rapidly expanding area of biomedical
research, generating considerable interest among consumers,
manufacturers, and regulators alike. This is a progressive
area; the field is continually conducting studies
and discovering possible benefits.
Though
blueberries themselves are not a cure-all, they contain
a number of substances which are thought to have health
benefits. These substances include, but are not limited
to fructose, fiber, vitamins and antioxidants. Antioxidants
thus far, seem to have the most conclusive role in
the prevention/ delaying of such diseases as cancer,
heart disease and the aging process however, a limited
number of studies, especially long term and on human
beings, are not available at this time.
What
is a Nutraceutical? Nutraceutical:
Any substance that may be considered a
food or part of a food that provides health benefits,
including the prevention or treatment of disease.
They range from isolated nutrients to genetically
engineered "designer foods".
The term
"nutraceutical" was coined by The Foundation for Innovation
in Medicine in 1989 to provide a name for this area
of biomedical research, and has since become part
of the standard lexicon in both the medical - scientific
community and in the food and drug industries (The
Foundation for Innovation in Medicine, 1991). The
wide acceptance of this term itself provides ample
testimony that a new product category is ready to
be born. Largely based on their cultural and historical
beliefs, Japan and many European countries hold established
places in the international marketplace for nutraceuticals.
They have long valued many natural substances that
hold preventative and therapeutic values, and have
a rapidly expanding body of research to back them
up. The United States, however, is at the beginning
of this process. Nutraceuticals have become a focal
point for updating the U.S. economic and regulatory
system in response to worldwide medical and scientific
trends.
Free
Radicals - Antioxidants:
Antioxidants are thought to help protect the body
against the damaging effects of free radicals and
the chronic diseases associated with the aging process
(Ames, 1993). Fresh fruits (blueberries) and vegetables
contain many of these naturally occurring antioxidants
such as vitamins A, C and E.
Blueberries
contain 0.04 mg of beta-carotene, 13 mg of vitamin C
and 1 mg vitamin E per 100 g of blueberries. Blueberries
contain 10 RE (Retinol Equivalents, a unit of vitamin
A) of vitamin A per 100 grams of blueberries.
The RDA for vitamin A is 1000 RE for men and 800 RE
for women. In addition, blueberries contain anthocyanins
and phenolics that can also act as antioxidants.
Ellagic
and Folic Acid: Although their modes of
action is still poorly understood, it appears that
these acids may inhibit cancer initiation. Ellagic
acid (in its most biologically active form, ellagitannin)
is found in blueberries and some other berries. (Stoner,
1989).
Folic acid
may help guard against cervical cancer (Toufexis,
1992), and may benefit the fetus during pregnancy.
Blueberries contain 6 ug./ 100g of folic acid. The
RDA for women is 180 ug.
Other
Substances: Antibacterial Agents: In Sweden,
dried blueberries are used to treat childhood diarrhea
(Kowalchuk, 1976). This use is attributed to anthocyanosides,
a natural substance found in blueberries which is
believed to be "lethal" to E. Coli (a bacteria sometimes
linked to the infection).
Fiber:
Multiple Health Benefits: Considerable
evidence collected over the last 20 years has proven
the numerous advantages of high fiber diets (Potter,
1986). Blueberries are a source of dietary fibers:
2.7g/100g. A diet containing 25g. of dietary fiber
per day is generally recommended.
Blueberries
contain a variety of compounds. These include: antioxidants,
anthocyanosides, bacterial inhibitors, folic acid,
vitamins A and C, carotenoids, ellagic acid, folic
acid, and dietary fibers. The significance of their
presence and modes of action remain largely unexplored.
Sources:
-
The
Foundation for Innovative Medicine, The Nutraceutical
Initiative: A Proposal for Economic and Regulatory
Reform. December1991
-
Kowalchuk
J. Antiviral Activity of Fruit Extracts. J
Food Science. 41: 1013-1017, 1976
-
Potter
N. Food Science 4th ed. Conn:
A VI 1986
-
Potter
N. Do Functional Foods Raise the Health Threshold.
The World of Ingredients. Oct.-Nov.
54-55, 1994
-
Stoner
G.. Ellagic acid: A Naturally Occurring Inhibitor
of Chemically-Induced Cancer. 1989
-
Toufexis
A. The New Scoop on Vitamins. Time 139(14).
1992
- Ames
BN, Shigenaga MK, Hagen TM. Oxidants antioxidants,
and the degenerative diseases of aging. Proc.
Natl. Acid. Sci. USA 90:7915-7922, 1993
|