General Description
Alpha lipoic acid, or ALA (also known as thioctic acid) is an antioxidant
fatty acid produced naturally in the body and found in foods such
as red meat, liver, brewer's yeast and green plants. ALA supplements
use the synthetic form dl-alpha lipoic acid.
Health applications
Primary functions
The body requires ALA for production of ATP (adenosine triphosphate),
the main source of cellular energy. ALA also acts as an antioxidant,
effective against both water-soluble and fat-soluble free radicals.1
Research shows that ALA also helps regenerate other antioxidants
inlcuding vitamin C, vitamin E,1,2 and glutathione.3-5
The antioxidant capabilities of ALA make it especially beneficial
for the immune system, the liver, and the cardiovascular system.
Cardiovascular health
The benefits ALA provides for the cardiovascular system stem from
its role as an antioxidant. Research shows that ALA inhibits the
oxidation of LDL (the "bad cholesterol").6 Oxidized
LDL is a major contributor to atherosclerosis. In vitro research
indicates ALA may inhibit atherosclerosis progression at its earliest
stages.7 ALA also works synergistically with vitamin
C to recycle vitamin E, a vitamin known to be essential for cardiovascular
health.
Diabetes
The most promising research on the health benefits of ALA supplementation
involves its potential in the treatment of type II diabetes
(non-insulin-dependent diabetes mellitus, or NIDDM). Research
indicates that ALA can enhance insulin sensitivity,8
improve glucose effectiveness,9 and enhance glucose
disposal10 in patients with NIDDM. Numerous other studies
show that ALA can improve symptoms of NIDDM-related nervous system
disturbances11-15 and cardiovascular problems.14-16
Because ALA supplementation may alter blood sugar and insulin
levels, people with diabetes should only take ALA under a physician's
supervision.
Immune system support
As an antioxidant, ALA may provide specific benefits for immune
system function. By increasing plasma and intracellular levels
of glutathione, ALA should, theoretically, improve the body's
resistance to a variety of illnesses. Many researchers believe
ALA may one day play an important role in treatment of human immuno-deficiency
virus (HIV). Although studies have shown that ALA can inhibit
replication of HIV in vitro,17-20 its effectiveness
in human subjects has not been established.
Dosage/toxicity
Although ALA is not considered to be essential in the diet because
it can be manufactured in the body, some scientists recommend
supplementing 20 to 50 mg per day to boost antioxidant levels.21
ALA has an excellent safety record, with no serious side-effects
reported in over 30 years of clinical research. Although studies
on diabetic patients have used as much as 1,800 mg of ALA per
day, there is little evidence of additional benefit in doses greater
than 600 mg per day.8,14 |
