General Description
A close relative of the American blueberry, bilberry (also known
as European blueberry, whortleberry, wineberry, huckleberry, or
trackleberry), is a shrubby perennial that grows in forests and
meadows throughout much of Europe. Growing up to 50 cm in height,
bilberry flowers from April to June, with greenish-pink, bell-shaped
blossoms. The fruit is a blue-black or purple berry with multiple
seeds. The meat of the bilberry is also purple, unlike the American
blueberry, which has cream-colored pulp. The ripe berries are used
to promote vision and circulatory health. Decoctions of the leaves
are used as a folk medicine treatment for diabetes.
Health Applications
History and Traditional Use
Bilberries have long been used as food, in much the same fashion
as the American blueberry. Dried berries have traditionally been
used in the treatment of diarrhea and dysentery, while decoctions
of the leaves have been used in the treatment of diabetes. Interest
in the medicinal use of bilberry was revived during World War II
when British Royal Air Force pilots reported improved nighttime
vision after eating bilberry preserves.
Chemical Composition
The primary active constituents in bilberries are flavonoid compounds
known as anthocyanidins, which exhibit powerful antioxidant activity.
Bilberry extracts are commonly standardized to 25% anthocyanidin
content, and this is the concentration used in most scientific
studies.
Bilberry and
Circulation
Bilberry's high antioxidant concentration makes it a good herb
for promoting cardiovascular health. Compounds in bilberry have
shown the ability to protect LDL cholesterol molecules from oxidative
damage.1 Oxidized LDL is a major contributor to atherosclerosis,
which can lead to heart attack or stroke. Anthocyanidins found
in bilberry help stabilize collagen structures and maintain capillary
strength, which may promote circulation to the eyes and to the
extremities.
Bilberry and
Eye Health
Much of the European research on bilberry has focused on the herb's
potential eye health benefits. Studies conducted in Germany indicate
bilberry may be helpful for people with diabetic retinopathy,
presumably by strengthening blood vessels in the retina and reducing
vascular permeability.2-3 Although bilberry extracts
have become very popular for promoting nighttime vision and helping
"night blindness," the herb's effectiveness in these areas has
not been demonstrated conclusively in scientific studies.
Dosage/Toxicity
Dosage of bilberry should be based upon its anthocyanidin content.
Most bilberry extracts are standardized to 25% anthocyanidin content,
and are commonly taken in 60-120 mg doses, three times daily.
Bilberry is well tolerated in this dosage range and devoid of
adverse effects. Excess anthocyanidin is excreted in the urine
and does not accumulate in the body in toxic levels.4
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