Many of the supplements at OVitaminPro contain L-carnitine or Acetyl-L-Carnitine. It would be helpful for you to know a few basic facts regarding this helpful nutrient.

Acetyl-L-Carnitine is an amino acid sometimes referred to as ALCAR. The body can make ALCAR but supplementation appears to be beneficial anyway as shown in studies that will be discussed a little later.

ALCAR appears to have its primary effects in the mitochondria, the energy production portion of the cell. This is especially true in the brain. ALCAR is an antioxidant and also helps in the production of acetylcholine, a neurotransmitter important in blood supply, memory and mood.

The general population has no minimum daily requirement of ALCAR like it does for vitamin C or B vitamins as the body can make it in sufficient quantities to maintain health at a basic level. Some people, however have a genetic makeup that limits the ability to synthesize L-carnitine and some liver and kidney diseases and some medications (especially anti-seizure) interfere with synthesis as well.

Studies indicate that L-carnitine works best in the presence of coQ-10 and is absorbed better when taken with an oil like fish oil.


We like to talk about doses as therapeutic or fundamental. A fundamental dose is the minimum required to keep the body going at its most basic level. A therapeutic dose is what is required to get a specific healing effect. Many articles you read about supplements don’t understand the difference between the two. For example, to avoid scurvy, very small amounts of vitamin C will work. To achieve an immune response, you may need 100 times that amount. Similar effects can be observed for vitamin D where small amounts to keep blood levels at 25 to 30 will keep the lights on so to speak but a much greater therapeutic dose might be needed to get levels up to 75 or 80.


And so it is with acetyl-L-carnitine. Eating dairy and meats can supply L-carnitine in sufficient quantities for basic life function. However if you are battling heart or brain degenerative problems you will want significantly more than you can get from a diet. Typical dose is 250 to 1000 mg 3x per day along with 100 to 200 mg coQ-10 with each dose of acetyl L-carnitine.

How do you know how much to take? Start with the lower dose and work up week by week until your body responds. You may need a third party to help you with the dose as sometimes it is hard to tell from the inside. An observant spouse or a knowledgeable nutritionist can help.

I will say it here and again at the end of this article. We insist that supplementation like L-carnitine should be coupled with proper testing to be sure you are getting the desired effect. I can’t be more specific than that because each case is a little different. Maybe home monitoring of some key marker like blood pressure or blood sugar is possible and meaningful and maybe you will need extensive lab work.

The following is a summary of some published articles about L-carnitine and acetyl-L-carnitine. I will add some references for those so inclined for a starting point for further reading.


Mayo Clin Proc. 2013 Jun;88(6):544-51. doi: 10.1016/j.mayocp.2013.02.007. Epub 2013 Apr 15. L-carnitine in the secondary prevention of cardiovascular disease: systematic review and meta-analysis. DiNicolantonio JJ1, Lavie CJ, Fares H, Menezes AR, O’Keefe JH

Carnitine might be a good addition to standard therapy for angina. In one controlled study, 200 individuals with angina (the exercise-induced variety) took either 2 g daily of L-Carnitine or were left untreated. All the study participants continued to take their usual medication for angina. Those taking Carnitine showed improvement in several measures of heart function, including a significantly greater ability to exercise without chest pain. They were also able to reduce the dosage of some of their heart medications (under medical supervision) as their symptoms decreased.

Another trial that did use a double-blind, placebo-controlled design tested L-Carnitine in 52 individuals with angina, and found evidence of benefit. In addition, several small studies (some of them double-blind) tested Propionyl-L-Carnitine for the treatment of angina, and also found evidence of benefit.


Atherosclerosis. 2013 Dec;231(2):456-61. doi: 10.1016/j.atherosclerosis.2013.10.013. Epub 2013 Oct 24. Gut microbiota metabolism of L-carnitine and cardiovascular risk. Ussher JR1, Lopaschuk GD, Arduini A.

People with advanced hardening of the arteries, or atherosclerosis, often have difficulty walking due to lack of blood flow to the legs. Pain may develop after walking less than half a block. Although Carnitine does not increase blood flow, it appears to improve the muscle’s ability to function under difficult circumstances.

A 12-month double-blind placebo-controlled trial of 485 patients with intermittent claudication evaluated the potential benefits of Propionyl-L-Carnitine. Participants with relatively severe disease showed a 44% improvement in walking distance as compared to placebo. However, no improvement was seen in those with mild disease. Another double-blind study followed 245 people and also found benefit.

Similar results have been seen in most but not all other studies of L-Carnitine or Propionyl-L-Carnitine. Propionyl-L-Carnitine may be more effective for intermittent claudication than plain Carnitine.


Ann Agric Environ Med. 2013;20(3):606-12. Comprehensive rehabilitation in chronic heart failure. Gąsiorowski A1, Dutkiewicz J.

Several small studies have found that Carnitine, often in the form of propionyl-L-carnitine, can improve symptoms of congestive heart failure. In one trial, benefits were maintained for 60 days after treatment with Carnitine was stopped.


Carnitine may help reduce death rate after a heart attack. In a 12-month placebo-controlled study, 160 individuals who had experienced a heart attack received 4 g of L-Carnitine daily or placebo, in addition to other conventional medication. The mortality rate in the treated group was significantly lower than in the placebo group, 1.2% versus 12.5%, respectively. There were also improvements in heart rate, blood pressure, angina (chest pain), and blood lipids. A larger double-blind study of 472 people found that Carnitine may improve the chances of survival if given within 24 hours after a heart attack. Note: Carnitine is used along with conventional treatment, not as a substitute for it.


Evidence from three double-blind placebo-controlled studies enrolling a total of 49 individuals suggests that L-Carnitine can improve exercise tolerance in COPD, presumably by improving muscular efficiency in the lungs and other muscles.


Numerous double- or single-blind studies involving a total of more than 1,400 people have evaluated the potential benefits of Acetyl-L-Carnitine in the treatment of Alzheimer’s disease and other forms of dementia. Early studies found some evidence of benefit, although it was generally quite modest. However, the two most recent and best-designed studies found no benefit.

A double-blind placebo-controlled trial that enrolled 431 participants for 1 year found no significant improvement at all in the group treated with Acetyl-L-Carnitine. A close look at the results appeared to suggest some benefit in individuals who developed Alzheimer’s disease at a particularly young age. However, when this possibility was tested in a 1-year double-blind placebo-controlled trial of 229 patients with early-onset Alzheimer’s, no benefits were seen.


A double-blind study of 60 seniors with mild depression found that treatment with 3 g of Carnitine daily over a 2-month period significantly improved symptoms as compared to placebo. Positive results were seen in another study as well.


Enlargement of the thyroid (goiter) can be due to many causes, including cancer and iodine deficiency. In some cases, thyroid enlargement occurs without any known cause, so-called benign goiter.

Treatment of benign goiter generally consists of taking thyroid hormone pills. This causes the thyroid gland to become less active, and the goiter shrinks. However, there may be undesirable effects as well. Symptoms of hyperthyroidism (too much thyroid hormone) can develop, including heart palpitations, nervousness, weight loss, and bone breakdown.

A double-blind, placebo-controlled trial found evidence that use of L-Carnitine could alleviate many of these symptoms. This 6-month study evaluated the effects of L-Carnitine in 50 women who were taking thyroid hormone for benign goiter. The results showed that a dose of 2 or 4 g of Carnitine daily protected participants’ bones and reduced other symptoms of hyperthyroidism.

Carnitine is thought to affect thyroid hormone by blocking its action in cells. This suggests a potential concern: Carnitine might be harmful for people who have low or borderline thyroid levels to begin with. This possibility has not been well explored as yet.


Peyronie’s disease is an inflammatory condition of the penis that develops in stages. In the first stage, penile pain occurs with erection; next, the penis becomes curved; finally, erectile dysfunction may occur. Many medications have been tried for Peyronie’s disease, with some success. One such drug is tamoxifen (better known as a treatment to prevent breast cancer recurrence.) A 3-month, double-blind study compared the effectiveness of Acetyl-L-Carnitine (1 gram twice daily) against tamoxifen; the study enrolled 15 men in the first stage of Peyronie’s disease and 33 men in the second stage. The result indicated that Acetyl-L-Carnitine reduced penile curvature while tamoxifen did not; the supplement also reduced pain and slowed disease progression to a greater extent than the drug. Furthermore, while the drug caused various side effects, the supplement caused none.


A 1996 review of clinical studies concluded that no scientific basis exists for the belief that Carnitine supplements enhance athletic performance. A few studies have found some benefit, but most have not.


L-Carnitine in its three forms appears to be quite safe. However, individuals with low or borderline-low thyroid levels should avoid Carnitine because it might impair the action of thyroid hormone.

Individuals on dialysis should not receive this (or any other supplement) without a physician’s supervision. The maximum safe dosages for young children, pregnant or nursing women, or those with severe liver or kidney disease have not been established.

L-Carnitine – Interaction Drug Side Effects You Should Know About

If you are taking;

•          Antiseizure medications, particularly valproic acid (Depakote, Depakene) but also phenytoin (Dilantin): You may need extra Carnitine.

•          Thyroid medication: Do not take Carnitine except under a physician’s supervision

I will repeat that use of higher doses of L-carnitine should be coupled with appropriate and meaningful testing to ensure that you are getting the physiological benefit you need without pushing another physiological system into stress. Get knowledgeable professional help if this isn’t your expertise.


Some examples of Acetyl L-Carnitine on are:

NuMedica Acetyl L-Carnitine 90c

Jarrow Acetyl L-Carnitine 120c