Leung's Encyclopedia of Common Natural Ingredients Used in Food, Drugs, and Cosmetics

found in for degenerative retinal conditions.7,8
Anthocyanosides extracted from the fruit have
shown diverse activities in animal studies: a
protective effect on the liberation of lactate
dehydrogenase in heart and plasma and cardi-
ac isoenzymes, indicating an angina-protect-
ing effect.^9 The anthocyanosides have also
shown retinal phosphoglucomutase and glu-
cose-6-phosphatase inhibiting activity;^10 a
hypoglycemic effect (due to neomyrtillin
content in leaves);^11 vasoprotective activity
(twofold as active in protecting capillary per-
meability as rutin); and antiedema activity.^12
A long-lasting increase in capillary resistance
produced by the anthocyanins of the fruit is
believed to result from their greater affinity
for the skin and kidney tissue rather than
plasma.^13 The anthocyanins decrease collagen
hydrolysis, significantly reducing permeabili-
ty of the blood–brain barrier.^14 Their vasodi-
lating effect stimulates local synthesis of
vasodilator prostaglandins;15,16 they also
inhibit platelet aggregation and thrombus
formation via stimulation of PGI 2 -like sub-
stances in vascular tissue.^17 Orally adminis-
tered to rats with experimental type 1 diabetes,
leaf extracts lowered plasma, glucose, choles-
terol, and triglyceride levels.^18

TOXICOLOGY

In mice and rats, the acute oral LD 50 of a
bilberry extract (standardized to contain 36%
anthocyanins) was greater than the equi-
valent anthocyanins at 720 mg/kg. Long-term
(6 months) oral administration of bilberry
extract equivalent to up to anthocyanins at
180 mg/kg/day failed to produce toxic effects;
no teratogenic or mutagenic effects were
found.^19 Prolongeduse oftheleavesmay result
in chronic intoxication. At a chronic dose of
1.5 g/kg/day, bilberry leaf caused toxicity and
eventual death of animals. Side effects of the
berries are unknown (BLUMENTHAL1). How-
ever, inhibition of platelet aggregation was
found after 30–60 days in human volunteers
taking an extract that provided 480 mg of
bilberry anthocyanosides per day.^20

USES

Medicinal, Pharmaceutical, and Cosmetic.

Fruit preparations, calculated at a daily dose

of 20–60 g, are used for the treatment of acute

diarrhea and for localized mild inflammation

of the mucous membranes of the mouth and

throat. In Europe, leaf preparations are used

for the supportive treatment of diabetes mel-

litus; prevention and treatment of gastrointes-

tinal, kidney, and urinary tract disorders, as

well as arthritis, dermatitis, functional heart

problems, gout, hemorrhoids, poor circula-

tion, and for metabolic stimulation of circula-

tion. Efficacy of the leaves is not established

and their therapeutic use is not recommended

(BLUMENTHAL1).

Food. The fruit is best known for its food

value; used in alcoholic and nonalcoholic

beverages; conserves, pastries, compote, syr-

ups, or eaten raw; fruit extracts also used as red

coloring in wine.

Dietary Supplements/Health Foods. Dried

fruits in encapsulated products; teas; primarily

for improved vision (BLUMENTHAL1).

Traditional Medicine. Historically, in

Europe, the fruits and to a lesser extent the

leaves, have been used for astringent and

antiseptic activities in diarrhea, dysentery,

dyspepsia, intestinal dyspepsia in infants; leaf

tea as antidiabetic.

COMMERCIAL PREPARATIONS

Crude berries or extract.

Regulatory Status. Regulated in the United

States as a dietary supplement. Both the leaves

and the fruits are subjects of German thera-

peutic monographs. Efficacy of leaves is not

documented; fruits allowed for acute diarrhea

and mild inflammation of mouth and throat

(BLUMENTHAL1;WICHTL).

94 Bilberry