Acetyl-L Carnitine is an amino acid that occurs naturally in the body and is also found in milk and red meat, in particular mutton. It is involved in the transport of fats to the mitochondria (energy producing cell structures of the cells). It also protects from stress and heals damaged nerves caused by injury. In January 2002 a team of researchers showed that Acetyl -L Carnitine combined with Alpha Lipoic Acid, a fatty acid, could delay the ageing process by increasing energy (see below). Acetyl -L Carnitine was found to nourish brain cells, protect from free radicals and stress, increase blood flow, reduce depression, improve cognitive abilities, and increase memory in the elderly. It is indicated in the treatment of Alzheimer, AIDS, depression, fibromyalgia, heart disease, memory loss, multiple sclerosis and stress.
Because L-carnitine is involved in cellular metabolism, acetyl-L-carnitine can help increase energy production in the mitochondria, the "power plants" of all cells, and thereby may generally boost physical and mental energy. As a dietary supplement, acetyl-L-carnitine is often used to help improve memory, and has been studied as a possible adjunct treatment for Alzheimer's disease. Acetyl-L-carnitine may also help address symptoms of depression, and may be useful in the treatment of Parkinson's disease, stroke, and Peyronie's disease. In addition, daily supplementation with acetyl-L-carnitine may have a protective effect on the central nervous system and may benefit the heart. There is also some evidence that acetyl-L-carnitine can enhance visual memory and attention in people with Down Syndrome, and clinical data indicates that it also may slow age-related mental decline that is not associated with Alzheimer's.
[Effect of the chronic treatment with L-acetylcarnitine in Down's syndrome].
SourceCattedra di Neurofisiopatologia, II Facoltà di Medicina e Chirurgia, Università degli Studi di Napoli.
AbstractNeuropsychologic tests were performed in subjects with Down syndrome in order to assess the effect of a 90-day treatment with L-acetyl-carnitine (LAC). Findings were evaluated statistically (Wilcoxon test) and compared to three further groups of subjects: untreated Down syndrome, mental deficiency due to other cases treated and not treated with LAC (Mann-Whitney U-test). Treated Down syndrome patients showed statistically significant improvements of visual memory and attention both in absolute terms and in comparison with the other groups. No improvement was found in mentally deficient non-Down subjects, so that the favourable effect of LAC appears to be specific for Down patients. In view of the analogies of the pathology and neurochemistry between Down syndrome and Alzheimer degenerative deficiency (deficit of cholinergic transmission) it is suggested that the action of LAC in these pathologies is related to its direct and indirect cholinomimetic effect.
L-acetylcarnitine may help with attention deficit hyperactivity disorder in children with the genetic disorder known as fragile X syndrome which results from an inherited genetic defect on the X chromosome. It is associated with mental retardation and may also cause autism and ADHD, Dr. Giovanni Neri from Universita Cattolica in Rome studied boys between 6 and 13 years old for a period one year. Twenty four received l-acetylcarnitine and 27 received placebo. There was a more effective reduction of hyperactivity and improvement of social behavior. American Journal of Medical Genetics 2008.
May be helpful in those with Alzheimer's disease since It protects against amyloid-beta neurotoxicity.
Effects of acetylcarnitine in Alzheimer's disease patients unresponsive to acetylcholinesterase inhibitors.
Curr Med Res Opin. 2003.
An evaluatation was made of the effect of 2 grams /day orally for 3 months in association with donepezil or rivastigmine in 23 patients with mild AD who had not responded to treatment with acetylcholinesterase inhibitors (AChE-I). The response rate, which was 38% after AChE-I treatment, increased to 50% after the addition of acetylcarnitine.
Anti-aging and longevity with alpha lipoic acid
Scientists at the University of California, Berkeley, CA rejuvenated aging rats by giving them a combination of alpha lipoic acid and acetylcarnitine. Lead researcher Dr Bruce Ames, said the results were astonishing: "With the two supplements together, these old rats got up and did the Macarena. The brain looks better, they are full of energy - everything we looked at looks more like a young animal." The animals' memories were also significantly improved. The two chemicals in combination have a positive impact on mini-organs within the body's cells called mitochondria and were able to mop up free radicals. Mitochondria generate energy within the cells and their deterioration is an important cause of aging.
It is difficult to predict whether this combination is effective in humans, and if so, how to determine the ideal dose combination. In the meantime, those who wish to supplement prudently with small amounts may consider taking about 5 to 10 mg of lipoic acid, and 30 to 100 mg of acetyl-l-carnitine. Since these nutrients are not often available over the counter in these small doses, you may need to open the capsules and take a portion.
Chronic fatigue syndrome
Exploratory open label, randomized study of acetyl- and propionylcarnitine in chronic fatigue syndrome.
Psychosom Med. 2004.
We compared 2 grams a day acetyl-L-carnitine, 2 g/d propionyl-L-carnitine, and its combination in 3 groups of 30 chronic fatigue syndrome patients during 24 weeks. Acetylcarnitine significantly improved mental fatigue and propionylcarnitine improved general fatigue.
Depression and low mood
ALCAR may benefit geriatric patients with mild depression.
Acetyl-L-carnitine in the treatment of diabetic neuropathy. A long-term, randomized, double-blind, placebo-controlled study.
Drugs R D. 2002.
A group of 333 patients with diabetic neuropathy were enrolled. Acetylcarnitine (or placebo) was given orally at a dosage of 2000 mg/day. This natural medicine was effective and well tolerated in improving neurophysiological parameters and in reducing pain over a 1-year period.
Acetyl L Carnitine Improves Pain, Nerve Regeneration, and Vibratory Perception in Patients With Chronic Diabetic Neuropathy: An analysis of two randomized placebo-controlled trials.
Diabetes Care. 2005.
We evaluated frozen databases from two 52-week randomized placebo-controlled clinical diabetic neuropathy trials testing two doses of acetyl-l-carnitine : 500 and 1,000 mg/day three times a day. Data showed significant improvements in sural nerve fiber numbers and regenerating nerve fiber clusters. Nerve conduction velocities and amplitudes did not improve, whereas vibration perception improved in both studies. Pain as the most bothersome symptom showed significant improvement in one study and in the combined cohort taking 1,000 mg.
Hypertension and insulin resistance
Ameliorating hypertension and insulin resistance in subjects at increased cardiovascular risk: effects of acetyl-L-carnitine therapy.
We prospectively evaluated the effects of 24-week oral acetyl-L-carnitine (1 g twice daily) therapy on the glucose disposal rate in nondiabetic subjects at increased cardiovascular risk. It safely ameliorated arterial hypertension, insulin resistance, impaired glucose tolerance, and hypoadiponectinemia.
Studies in aging rats shows chronic administration of acetyl-l-carnitine increases cholinergic synaptic transmission and consequently enhances learning capacity. The memory of aging rats is rejuvenated by giving them a combination of acetylcarnitine and lipoic acid.
A pilot study on the effect of acetylcarnitine in paclitaxel- and cisplatin-induced peripheral neuropathy.
Twenty-seven patients with paclitaxel and/or cisplatin-induced neuropathy received at least one cisplatin or one paclitaxel based regimen, or a combination of both. Patients with chemotherapy-induced peripheral neuropathy were treated with acetyl-L-carnitine 1 g/die i.v. infusion over 1-2 hours for at least 10 days and it seemed to be an effective and well-tolerated agent for the treatment of chemotherapy-induced peripheral neuropathy.
ALCAR is more effective than tamoxifen in the therapy of acute and early chronic Peyronie's disease.
Vision research study
Improvement of visual functions and fundus alterations in early age-related macular degeneration treated with a combination of acetyl-L-carnitine, n-3 fatty acids, and coenzyme Q10.
The aim of this randomized, double-blind, placebo-controlled clinical trial was to determine the efficacy of a combination of acetyl-L-carnitine, n-3 fatty acids, and coenzyme Q10 (Phototrop) on the visual functions and fundus alterations in early age-related macular degeneration. Findings suggest that an appropriate combination of compounds which affect mitochondrial lipid metabolism, may improve and subsequently stabilize visual functions, and it may also improve fundus alterations in patients affected by early age-related macular degeneration.
Some people notice ALC reduces appetite but I have not seen formal studies using this supplement as an effective weight loss pill.
Various forms manufactured and provided by Sigma Tau corp:
Acetyl L-Carnitine hydrochloride
There has not been enough research with each of these forms of ALCAR to determine which are best for long term human consumption.
I'm passing on to you information about this product that was posted at Life Extension: "Acetyl-L-carnitine arginate dihydrochloride has several valuable properties. The attachment of an arginine molecule gives this compound a number of additional benefits for the aging brain. Acetyl-L-carnitine arginate appears to mimic the effects of a protein called nerve growth factor that supports the survival of neurons in areas of the brain associated with emotion, such as the hippocampus, and in the forebrain, which is associated with cognition, emotion, and important body functions."
I have not seen human studies with this form, and hence any statements such as the one above are speculative and premature. I am not aware of studies comparing the two forms and hence there is no evidence that we know of that one form is superior to the other.
Those who take carnitine pills notice an increase in physical energy, but not as much mental energy. Acetyl l-carnitine has a more immediate and noticeable mental effect than carnitine because it crosses into the brain much better and quicker. The mind boosting effect of ALC is often noticed within a few hours, or even within an hour. Most people report feeling mentally sharper, having more mental stamina, having more focus and being more alert. Some find a mild mood enhancement.
The typical daily dosage for long term use is 100 to 300 mg once a day, preferably in the early part of the day. Higher amounts, such as 500 to 1000 mg, can be taken for short periods. Most people begin to notice the effect from after an hour or two, and the mental enhancement can last a few hours or all day depending on the dosage. There are many different dosages available over the counter ranging from 100 mg to 500 mg or more.
I give Jett (weighs about 22 lbs) two servings of about 500 mg each serving w/food. Once in am and once in the afternoon. I see that this dose is high. I haven't seen any hyperactivity, though. He still takes his nap fine and falls asleep at night.
Acetyl-L-carnitine is a powerful anti-aging nutrient that is beneficial for mild mental impairment; practitioners recommend 1,000 to 2,000 mg a day for up to ninety days.
Power Aging by Gary Null, page 192 Results of this double-blind, placebo-controlled study found that treatment with 2 g of acetyl-L-carnitine per day for 24 weeks had beneficial short-term memory effects on patients with Alzheimer-type dementia.
The Clinician's Handbook of Natural Healing by Gary Null PhD, page 711
Several major studies have shown that daily supplementation with ALC significantly slows the progression of Alzheimer's disease, resulting in less deterioration in memory, attention and language, and spatial abilities.
Prescription for Nutritional Healing by Phyllis a Balch CNC and James F Balch MD, page 46
Results of this double-blind, placebo-controlled study showed that the administration of 2g per day of acetyl-L-carnitine for three months led to significant improvements in elderly patients suffering from mental impairment.
The Clinician's Handbook of Natural Healing by Gary Null PhD, page 854
Elderly patients receiving acetyl-L-carnitine at doses of 1,000 to 2,000 mg a day for up to ninety days found relief from mild mental impairments such as slow memory.
Power Aging by Gary Null, page 93
Results of this double-blind, placebo-controlled study indicated that the administration of 1500 mg per day of acetyl-L-carnitine to elderly patients with mild mental impairments proved to be beneficial against cognitive and emotional-affective mental impairment.
The Clinician's Handbook of Natural Healing by Gary Null PhD, page 706
Side effects include mild gastrointestinal symptoms, such as nausea, vomiting, and abdominal cramps, as well as headache; an increase in agitation or restlessness; and an increase in seizure frequency in persons with seizure disorder. Persons with Alzheimer's disease may exhibit psychiatric disturbances, such as depression and confusion, but it is uncertain whether these effects are due to acetyl-L-carnitine or the disease itself. Some evidence suggests acetyl-L-carnitine may interfere with thyroid metabolism.
At least in eyes, it appears that acetyl-L-carnitine may have antiglycation abilities (55). Hendlor and Rorvik report, “”Acetyl-L-carnitine has recently demonstrated some efficacy as a possible neuroprotective agent for strokes, Alzheimer’s disease, Down’s syndrome and for the management of various neuropathies…recent studies show beneficial effects in Alzheimer’s disease. Younger patients seem to benefit most” (55). However, some few with seizure disorders have reported increases in seizure frequency or severity on acetyl-L-carnitine (54). As the DS population is much more inclined towards seizure disorders than the general public (56), caution would seem to be advisable regarding using acetyl-L-carnitine to attempt to prevent glycation.
54. Hendlor SS, Rorvik D, eds. PDR for Nutritional Supplements. Medical Economics. Montvale (NJ) 2001
55. Swamy-Mruthinti S, Carter AL. Acetyl- L -carnitine decreases glycation of lens proteins: in vitro studies. Exp Eye Res. 1999;69(1):109-115
56. Thiel R, Fowkes SW. Down syndrome and epilepsy: A nutritional connection? Med Hypo. 2004; 62(1):35-44
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