Alternative Names: Thiotic Acid or Thioctic Acid
Discovered in 1951, lipoic acid (also called alpha-lipoic acid or ALA) has long been recognized as a coenzyme that helps break down sugar for energy production during the Krebs cycle. Only recently has its therapeutic potential been realized.
Lipoic Acid is considered to be among the elite, multipurpose
antioxidants and has been variously called "the universal
antioxidant" or the "ideal oxidant". You can think of lipoic acid as a kind of "wild card" antioxidant. Evidence shows that even if you are not getting enough
vitamin C or E, for example, lipoic acid supplements can make up at least part of the deficit. Lipoic acid is considered a conditionally vital antioxidant nutrient. Specifically, the body makes some of its own lipoic acid, but we still need to get most of it form external sources, either from food, such as meat, or supplements. Our ability to make lipoic acid does decline with age.
The supplemental use of lipoic acid is expected to have huge impacts on health in the future. Almost any portion of the body can use increased levels of lipoic acid
Source
Alpha
Lipoic Acid can be found in potatoes, carrots, broccoli,
yeast, beets, yams and kohlrabi, and is also abundant in red meat. It is a vitamin-like
antioxidant that is also produced naturally in the body. It is also supplied in 25, 50, 100, and 200mg capsules.
Function; Why it is Recommended
Lipoic Acid is the only
antioxidant that is fat- and water-soluble. This property has made it a perfect electron transporter for both oxidized
ascorbic acid (water-soluble) and
vitamin E (fat-soluble); it is easily absorbed and transported across cell membranes. Whereas many
antioxidants only provide protection outside of cells, ALA is broken down inside cells to dihydrolipoic acid - an even more potent antioxidant. It also regenerates other antioxidants like
vitamin C, vitamin E and
glutathione.
Lipoic acid fights
free radical damage in both fatty and watery regions of cells and helps to recycle other antioxidants in what is described as "antioxidant
synergism". A recent study showed that when lipoic acid was missing, other antioxidants did not interact well, thereby reducing their ability to protect cells. [
Packer, L., et al. "Alpha-lipoic acid as a biological antioxidant," Free Radical Biol & Med. 19(2): pp.227-50, 1995]
In addition to its ability to scavenge
free radicals on its own, Lipoic Acid also enhances the actions of many other antioxidants such as glutathione and vitamin E. It can either substitute for them when they are deficient, or help to recycle them after they have neutralized free radical molecules. Lipoic acid contains two thiol (sulfur) groups which allows it to reduce oxidized glutathione.
Lipoic acid, like
insulin, reduces
glycation, enhancing the movement of blood sugar into our cells. It promotes greater energy production by muscles and reduces the amount of
glucose stored as fat.
Lipoic Acid protects the
liver from alcohol damage, the
lungs from smoke damage, and enhances
glucose disposal in type II
diabetes and reduces associated
neuropathy and
cataracts. Individuals with capillary fragility (
bruise easily) can benefit.
In addition to being a powerful
antioxidant, lipoic acid has an important role in controlling blood sugar. Through both of these mechanisms, it may help prevent the negative effects of having an even slightly elevated blood sugar causing some of the serious side-effects of
diabetes (nerve damage, pain, blindness, heart disease and accelerated aging). It may even help repair some of the nerve damage that may have occurred by encouraging new nerve growth.
It is medically approved in Germany for treating adult-onset type II diabetes and its complications. Ironically, the research that demonstrated its increased blood sugar utilization was done in the United States.
Lipoic acid is not a controlling factor in such instances, but research shows that a high intake (300 to 600mg per day) tends to normalize blood sugar levels in
diabetics. [
Haugaard, N., et al. "Stimulation of glucose utilization by thioctic acid," Biophys Acta 222: pp.583-6, 1970]
Clinical applications for this nutrient include the following conditions:
Diabetic polyneuropathy, cataracts,
glaucoma, ischemia-reperfusion injury, radiation injury, metal toxicity, Amanita mushroom poisoning and CCl4 poisoning. Because of its unique characteristics ALA is likely to have therapeutic application in a wide range of additional clinical conditions.
Studies in the late 1990s demonstrated that lipoic acid stops
cholesterol and intracellular damage by
free radicals, discourages the formation of active species, inhibits growth of cancer cells and, possibly, even improves memory.
Lipoic acid is also a super-chelator, capable of removing form our bodies excess
iron,
calcium,
copper, toxic molecules such as cadmium, lead and mercury, as well as organic hydrocarbons.
Lipoic acid is used therapeutically for a variety of conditions including
chemical hypersensitivity syndrome, heavy metal toxicity,
diabetic neuropathy, chronic aggressive
hepatitis, elevated
liver enzymes and liver toxicity.
The U.S. National Institutes of Health (NIH) considers α-lipoic acid to be the only approved antidote for mushroom (Amanita) poisoning (although milk thistle extracts are a much more proven natural product for this use).
Instructions
No RDA has been established. Humans are usually not deficient in alpha-lipoic acid, but supplementation can help in some conditions. While some human studies involve doses as high as 1,000mg daily, 100mg is sufficient to obtain the
antioxidant effects in most cases.
The recommended "therapeutic dose" for healthy adults is 100-200mg. By contrast, animal studies have shown the acute toxic dose to be ten times that of the therapeutic dose. It may be taken once a day with any supplement or food.
Side-Effects; Counter-Indicators and Warnings
Lipoic acid is safe with no side-effects except for possible toxicity in
diabetic patients. In over three decades of use in Europe, no study has shown any serious adverse effects of taking lipoic acid supplements. Diabetic patients should have blood sugar monitored if lipoic acid is to be taken as it is known to improve sugar metabolism and may change
insulin needs.
At the time of writing there was no known interference with any other drugs.