Acetyl-L-Carnitine (ALCAR, ALC or LAC) is a synthesized version of L-Carnitine. Which is a derivative of the amino acids lysine and methionine.
ALCAR is more bioavailable than L-Carnitine. It easily crosses the blood-brain barrier. And delivers L-Carnitine across cell membranes (which it would not be able to cross on its own).
L-Carnitine is naturally made in your liver and kidneys. And then transported to other tissues including your brain and heart.
ALCAR helps:
- Brain Energy Metabolism. ALCAR helps transport of fatty acids into mitochondria where they’re needed for energy metabolism. Fueling your cells “power plants” can boost physical and mental energy.
- Neurotransmitters. ALCAR is a necessary ingredient for acetylcholine formation. Which boosts memory, mental alertness, and fluid thought.
- Brain Optimization. The antioxidant properties of Acetyl-L-Carnitine provides neuroprotective qualities, boosts Brain-Derived Neurotrophic Factor (BDNF), and promotes cerebral blood circulation.
Overview
L-Carnitine is an amino acid that’s synthesized in your body. You also get it from red meat and dairy.
L-Carnitine is considered a “conditionally essential” nutrient because when your body uses it faster than it can produce it, you need supplemental L-Carnitine either from food or a supplement.
L-Carnitine is used throughout your body. Here we’re talking about the Acetyl-L-Carnitine form of L-Carnitine because of its affects on brain health and chemistry.
L-Carnitine vs. Acetyl-L-Carnitine: What’s the Difference?
L-Carnitine and Acetyl-L-Carnitine are often referred to as Carnitine. But each are structurally different, and each has its advantages.
L-Carnitine: Provides energy for the mitochondria of your cells, but is not capable of crossing the blood-brain barrier. Supplemental L-Carnitine is difficult for your body to absorb; only 18% of it reaches your bloodstream.
L-Carnitine is favored by athletes and dieters who want Carnitine’s fat-metabolizing benefits. But are not seeking any brain benefits.
Acetyl-L-Carnitine: Is easier to absorb and used by your body than L-Carnitine. One study showed using 2 grams daily for 50 days boosted blood ALCAR levels by 43%.[i]
ALCAR does everything that L-Carnitine does, but can also cross the blood-brain barrier. In another study, researchers found that ALCAR protects brain cells from oxidative stress, while L-Carnitine does not.[ii]
How does Acetyl-L-Carnitine Work in the Brain?
Acetyl-L-Carnitine boosts brain health and function in several ways. But two in particular stand out.
- ALCAR boosts acetylcholine, a neurotransmitter tied to memory and overall brain function.Acetyl-L-Carnitine is a precursor to acetylcholine in the presence of Coenzyme-A. ALCAR donates a “methyl group” to make acetylcholine.[iii]
Alzheimer’s-diseased brains show a 25% to 40% reduction in carnitine acetyltransferase, a brain enzyme that works with L-Carnitine & Acetyl-L-Carnitine.
This brain enzyme decline led researchers to link low ALCAR with low acetylcholine, and Alzheimer’s onset. They went on to suggest ALCAR as a viable therapy for brain regeneration.[iv]
- ALCAR promotes brain energy by fueling your brain cell’s mitochondria.[v]
ALCAR works as a shuttle transport for fatty acids through cell membranes. Right to the cell powerplant mitochondria.[vi]
- As ALCAR shuttles fatty acids into mitochondria, it provides the fuel that is burned for energy.
- As ALCAR shuttles fatty acids out of mitochondria, it flushes out toxic byproducts.
ALCAR maintains mitochondria in nearly every cell of your body. Your brain consumes at least 20% of your body’s energy. And generates a lot of toxic byproducts. So ALCAR is particularly important for a healthy brain.
How things go bad:
As we get older, our brain chemistry and energy metabolism changes.[vii]
↓ Nerve growth factor in the brain declines
↓ Acetyl-L-Carnitine levels decline
↓ Acetylcholine levels decline
↓ Mitochondria loses efficiency
All of these age-related changes are contributing factors to the neurodegenerative diseases of aging, including Alzheimer’s and dementia.
ALCAR to the rescue.
Research from the Linus Pauling Institute at Oregon State University shows that Acetyl-L-Carnitine will:[viii]
- Restore efficient mitochondrial energy production
- Replenish age-related changes to mitochondrial structure
- Replenish ALCAR and acetylcholine levels in the brain and body
ALCAR’s has the ability to boost acetylcholine and rejuvenate brain cells (including mitochondria). This has been proven to benefit those with age-related brain diseases like Alzheimer’s and major depression.[ix]
How does Acetyl-L-Carnitine feel?
You may not feel ALCAR… unless you’re elderly or have Erectile Dysfunction. Within those specific groups, Acetyl-L-Carnitine helps with memory, mood, mental performance and the ability to get and maintain an erection.
ALCAR’s brain support and its ability to fuel the mitochondria in your brain cells should boost cognition in all age and gender groups.
As a nootropic, ALCAR user reviews report a boost in energy and quick thinking.
The Research
In one study, researchers showed that ALCAR may have positive effects for depression and dementia.[x]
Another study out of Italy; researchers showed that Acetyl-L-Carnitine stimulated the growth of new neurites. More of these minute projections from nerve cell bodies meant increased signaling between cells throughout the central nervous system (brain and spinal cord).[xi]
And a study conducted at the Mount Sinai School of Medicine in New York found that ALCAR has potential in treating the symptoms of Parkinson’s Disease. By directly affecting mitochondrial respiration and assisting dopamine neurons and the use of dopamine in the brain.
ALCAR helps with Mild Cognitive Impairment (MCI)
A gold-standard double-blind, randomized controlled trial on 1,204 people showed significant effect on attention, mental performance, memory and higher mental functions.[xii]
In this study ALCAR seemed to ward off further brain deterioration. And could be considered as therapy for brain degeneration.
Acetyl-L-Carnitine slows rate of cognitive decline
130 Alzheimer’s patients were given ALCAR or a placebo daily for a year. They were tested across 14 points of cognitive performance.
This research showed a slower decline in cognitive performance with the ALCAR group compared to the placebo group.[xiii]
ALCAR effective for Chronic Fatigue Syndrome
Acetyl-L-Carnitine has been shown to improve fatigue in patients with chronic fatigue syndrome.
In a randomized, double-blind, crossover study; 36 people were treated for 3 months with either amantadine (used to treat Chronic Fatigue), or 1 gram of ALCAR twice daily.
The results of the study showed that ALCAR was better tolerated and more effective than the pharmaceutical for fatigue.[xiv]
Acetyl-L-Carnitine protects from oxidative damage of Ecstasy (MDMA)
Research has shown ALCAR to be effective in protecting your mitochondria from oxidative stress. But these guys took it a step further.
Male rats were given Acetyl-L-Carnitine before a dose of Ecstasy (MDMA). ALCAR pretreatment “exerts effective neuroprotection against MDMA-induced neurotoxicity at the mitochondrial level”, said the researchers.[xv]
Keep that in mind before your next party.
ALCAR for Erectile Dysfunction?
In this study, 120 patients were split into 3 groups. Group 1 was given 160 mg of testosterone per day. The 2nd group was given 2 grams of Propionyl-L-Carnitine plus 2 grams of Acetyl-L-Carnitine per day. And the 3rd group a placebo.
Did you know that there’s an International Index of Erectile Function?
Turns out the Propionyl-L-Carnitine/Acetyl-L-Carnitine stack was better than testosterone for erectile dysfunction. Without the side effects of an enlarged prostate, better orgasms, more sexual desire and improved mood.[xvi]
Dosage Notes
- Acetyl-L-Carnitine suggested dosage for cognitive benefits is 1 – 4 grams per day.
- For improved mood and elimination of chronic fatigue, 1 – 3 grams of ALCAR per day.
- For age-related memory concerns, 1 – 2 grams of ALCAR per day.
ALCAR is water-soluble and can be taken on an empty stomach with water. A few supplement manufacturers recommend taking their Acetyl-L-Carnitine with a meal. Which implies that it’s fat-soluble for which I’ve found no evidence in the scientific literature.
Side Effects
Acetyl-L-Carnitine is produced naturally in your body. So is considered well-tolerated and safe.
Side effects are rare but can include nausea, vomiting, increased agitation, weight loss, and restlessness.
You can also see an increase in seizure frequency if you have any kind of seizure disorder.
Available Forms
- Acetyl-L-Carnitine: L-Carnitine with an extra acetyl group. This version is more bioavailable and easily crosses the blood-brain barrier.
- L-Carnitine: This is the standard form of carnitine found in food.
- Lipo-Carn®: A proprietary blend of Alpha-Lipoic Acid and Acetyl-L-Carnitine. Studies show this combination is a powerful anti-aging duo.
Together, these two help combat diabetes, boost energy production, maintain proper cognitive function, protects the body from radiation and chemical toxins and helps immunity.[xvii] - Propionyl-L-Carnitine: L-Carnitine combined with propionic acid. This form is noted for its antioxidant activity, and is used for heart health applications. Also useful for erectile dysfunction.
Nootropics Expert Recommendation
Acetyl-L-Carnitine 500 – 1,500 mg per day
We recommend using Acetyl-L-Carnitine as a nootropic supplement.
Your body does synthesize some ALCAR on its own. And from the food you eat. But most Acetyl-L-Carnitine comes from red meat. And unless you eat a lot of great quality grass-fed beef or mutton…
ALCAR is especially helpful for those suffering from age-related cognitive decline. Studies show it helps stop or reverse brain degeneration with Alzheimer’s Disease, and depressive disorders. Particularly in the early stages of the disease.
We suggest starting with a dose of 500 mg daily. ALCAR is a great compliment to a stack including Piracetam. Add a choline source (Alpha GPC or CDP-Choline) at a ratio of 1:4. 1 gram of Alpha GPC to 4 grams of Piracetam. Take enough choline to eliminate a racetam-induced headache. Then add 500 mg of ALCAR.
Some have found ALCAR stacked with Coenzyme Q-10 has a profound effect on everything from mood to bipolar disorder. Especially combined with Alpha-Lipoic Acid.
Age-related cognitive disorders like Alzheimer’s may want to up the dose to 1,500 mg per day.
[i] Rebouche C.J. “Kinetics, pharmacokinetics, and regulation of L-carnitine and acetyl-L-carnitine metabolism.” Annals of the New York Academy of Sciences 2004 Nov;1033:30-41. (source)
[ii] Liu J., Head E., Kuratsune H., Cotman C.W., Ames B.N. “Comparison of the effects of L-carnitine and acetyl-L-carnitine on carnitine levels, ambulatory activity, and oxidative stress biomarkers in the brain of old rats.” Annals of the New York Academy of Sciences2004 Nov;1033:117-31. (source)
[iii] White H.L., Scates P.W. “Acetyl-L-carnitine as a precursor of acetylcholine.” Neurochemical Research 1990 Jun;15(6):597-601. (source)
[iv] Kalaria R.N., Harik S.I. “Carnitine acetyltransferase activity in the human brain and its microvessels is decreased in Alzheimer’s disease.”Annals of Neurology 1992 Oct;32(4):583-6. (source)
[v] Berg J.M., Tymoczko J.L., Stryer L. Biochemistry. 5th edition. New York: W H Freeman; 2002. (source)
[vi] Berg J.M., Tymoczko J.L., Stryer L. Biochemistry. 5th edition. New York: W H Freeman; 2002. (source)
[vii] Costell M., O’Connor J.E., Grisolía S. “Age-dependent decrease of carnitine content in muscle of mice and humans.” Biochemical and Biophysical Research Communications 1989 Jun 30;161(3):1135-43. (source)
[viii] Gomez L.A., Heath S.D., Hagen T.M. “Acetyl-L-carnitine supplementation reverses the age-related decline in carnitine palmitoyltransferase 1 (CPT1) activity in interfibrillar mitochondria without changing the L-carnitine content in the rat heart” Mechanics of Aging Development 2012 Feb-Mar; 133(0): 99–106. (source)
[ix] Pettegrew J.W., Levine J., McClure R.J. “Acetyl-L-carnitine physical-chemical, metabolic, and therapeutic properties: relevance for its mode of action in Alzheimer’s disease and geriatric depression.” Molecular Psychiatry 2000 Nov;5(6):616-32. (source)
[x] Ferrari F., Gorini A., Villa R.F. “Functional proteomics of synaptic plasma membrane ATP-ases of rat hippocampus: effect of l-acetylcarnitine and relationships with Dementia and Depression pathophysiology.” European Journal of Pharmacology 2015 Jun 5;756:67-74. (source)
[xi] Taglialatela G., Navarra D., Olivi A., Ramacci M.T., Werrbach-Perez K., Perez-Polo J.R., Angelucci L. “Neurite outgrowth in PC12 cells stimulated by acetyl-L-carnitine arginine amide.” Neurochemical Research 1995 Jan;20(1):1-9. (source)
[xii] Montgomery S.A., Thal L.J., Amrein R. “Meta-analysis of double blind randomized controlled clinical trials of acetyl-L-carnitine versus placebo in the treatment of mild cognitive impairment and mild Alzheimer’s disease” International Clinical Psychopharmacology 2003 Mar;18(2):61-71. (source)
[xiii] Spagnoli A. et. Al. “Long-term acetyl-L-carnitine treatment in Alzheimer’s disease.” Neurology. 1991 Nov;41(11):1726-32. (source)
[xiv] Tomassini V., Pozzilli C., Onesti E., Pasqualetti P., Marinelli F., Pisani A., Fieschi C. “Comparison of the effects of acetyl L-carnitine and amantadine for the treatment of fatigue in multiple sclerosis: results of a pilot, randomized, double-blind, crossover trial.” Journal of Neurological Science 2004 Mar 15;218(1-2):103-8. (source)
[xv] Alves E. et. Al “Acetyl-l-carnitine provides effective in vivo neuroprotection over 3,4-methylenedioximethamphetamine-induced mitochondrial neurotoxicity in the adolescent rat brain” Cellular Neuroscience Volume 158, Issue 2, 23 January 2009, Pages 514–523 (source)
[xvi] Cavallini G., Caracciolo S., Vitali G., Modenini F., Biagiotti G. “Carnitine versus androgen administration in the treatment of sexual dysfunction, depressed mood, and fatigue associated with male aging.”Urology 2004 Apr;63(4):641-6. (source)
[xvii] Liu J., Head E., Gharib A.M., Yuan W., Ingersoll R.T., Hagen T.M., Cotman C.W., Ames B.N. “Memory loss in old rats is associated with brain mitochondrial decay and RNA/DNA oxidation: partial reversal by feeding acetyl-L-carnitine and/or R-alpha -lipoic acid.” Proceeding of the National Academy of Sciences of the United States of America 2002 Feb 19;99(4):2356-61. (source)
I was wondering why a basic piece of information regarding the use of the various supplements (i.e. Water or fat soluble ) is rarely provided anywhere, including from the suppliers of the nootropics themselves.
Michael.
Michael, not an easy question to answer. I imagine some of the marketing people for these companies are not aware of fat- vs. water-soluble.
A few supplement makers include in a supplement’s directions to take it with a meal. The implication there is that the meal provides enough fat for the supplement to be absorbed by your body.
It’s really up to every neurohacker to become very familiar with each supplement in their stack. And find out if it’s water- or fat-soluble. I’ve included that information in the “Dosage Notes” section of each nootropic written about here on Nootropics Expert. Hope that helps.
Hi David,
Thanks for the great information, can you tell me if better to take ALCAR with food or on an empty stomach. My web research is yielding mixed results.
Paul, ALCAR is fat soluble so take it with food that has a decent amount of healthy fats. Or like I do with a tablespoon of organic coconut oil. ALCAR is processed in your gut (obviously) using two of the same transporters that helps it cross the blood-brain barrier; OCTN2 and B(0,+) transporters.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2278553/
I’ve found ACAL a great supp to stack with my other brain boosters, and the effects are very notieable with and without ACAL. However if I go beyond 500g a day I get excessive blood thinning and my nose literally pours a watery blood. I take nothing else that thins my blood but I have noticed a similar effect from some other amino forms and also taurine, so I assume I am one of those with a natural tendency to have thin blood.
Jay, blood thinning is one of the few side effects of using ALCAR. Thanks for your comment.
Hi David,
Thanks for all the information! I’m really enjoying your videos and texts. Could you give me your opinion on my case, please?
I’m 27 and I was recently diagnosed with Multiple sclerosis (I’m not taking any specific treatment), I’ve been taking vitamin D for 2 months (5000 i.u.) and started to feel dizzy, so I stopped.
I have always been a very positive and communicative person, but I have been feeling anxious, discouraged, with repetitive negative thoughts, and difficulty in sleeping. Three days ago I started taking a supplement (below follow the composition) to boost my mood and cognition (since I’m a student). After taking the supplement and a coffee this morning I was feeling very happy (more than usual) however, after ~1 hour I started feeling very accelerated and with a bad feeling, especially after taking a strong tea (high caffeine concentration). This sensation lasted for about 1hour. Actually, I have an accelerated metabolism and sometimes if I take like 2 or more coffees I feel very accelerated (my heart too) and with a bad feeling. However, I drink a cup of coffee every morning and it’s ok.
Do you thinking the supplements I’m taking could be bad for me?
Thank you! Nayara
……
Acetyl-L-Carnitine 100 mg,
L-theanine 100 mg,
Taurine 100 mg,
caffeine 75 mg,
Vitamin C 40 mg,
Vitamin B3 32 mg,
Zinc 20 mg,
Vitamin B5 12 mg,
Vitamin B6 7,98 mg
Vitamin B1 3,3 mg
Vitamin B2 2,8 ug
Folate 100 ug
Vitamin B7 100 ug
Selenium 82,5 ug
Vitamin B12 20 ug
Omega 3 893 mg (EPA 410 mg/DHA 250 mg)
Vitamin E 6 mg
Vitamin D3 25 ug
Magnesium citrate 2x 150 mg
Nayara, The dosage of each of the supplements you are taking in this stack are very low. So low in fact that most will not provide much therapeutic benefit at all. On a more positive note, the synergy with many of these compounds working together will boost their effectiveness somewhat. It is certainly not “bad” for you.
It seems caffeine is causing you problems. You already have the equivalent of the caffeine dose of one coffee in this supplement. It sounds like you are having a negative reaction from additional caffeine. You can counteract this effect by using L-Theanine. Either with a L-Theanine supplement. Or preferably drinking 3 or 4 cups of green tea throughout your day. See my review on L-Theanine here on Nootropics Expert.
This is what I would do if I was diagnosed with MS. I would learn everything I could about this disease. What causes it, and what it is doing to my body and brain. Study it until I understood what is going on. Then look for ways to either “fix” it or keep it under control.
Multiple sclerosis involves the loss of a specific type of cell that is required for making myelin. Myelin is the sheath surrounding axons in your brain and body. Axons send signals between neurons. Think of myelin as electrical tape wrapped around an electrical wire which protects the wire. If the electrical tape is removed, the wire is exposed and can short-circuit. And quickly burn out.
This destruction of myelin seems to be caused by your autoimmune system attacking this myelin sheath because it identifies it as the enemy.
I’m not a doctor. Don’t even play one on TV. This is my understanding of MS after about 30 minutes of research before responding to your question. My point is this…
Learn all you can about this disease. Then use resources like Nootropics Expert to search for ways to boost your immune system. And keep the inflammatory proteins that attack myelin in check. Then look for ways to rebuild myelin.
Ashwagandha for example helps regenerate axons and dendrites of brain nerve cells. And helps reconstruct synapses, the junctions where nerve cells communicate with other cells.
Pine Bark Extract (Pycnogenol) inhibits proinflammatory gene expression. You need Vitamin B6 to help control inflammation in your brain. B6 suppresses the inflammatory cytokines interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α). The inflammation that is likely contributing to myelin destruction.
Vitamin B1 (Thiamine) also contributes to the production of the enzyme PDH which is essential for making the neurotransmitter acetylcholine. And for the synthesis of myelin, which forms a sheath around the axons of neurons.
“Feeling anxious, discouraged, with repetitive negative thoughts, and difficulty in sleeping” is a perfectly natural reaction to being diagnosed with something like MS. The best way to turn this around is to do whatever you can to take back control of your own health. You can do this. I did and it saved my life. I’m not saying that you can completely “heal” yourself. But taking back control as you are starting to do will make all the difference. And take action with what you learn.
I have weird problem with ALCAR.
When I am taking it, I feel no effect (low dosage – 500 mg), or I am becoming tired (1000-1500 mg dosage).
What can be the problem?
Thomas, it could be the ALCAR is simply not for you. If a higher dosage of ALCAR causes fatigue it usually means too much acetylcholine. Same thing happens when using too much Alpha GPC or CDP-Choline.
does ALCAR need to be cycled or can we become resistant to it?
JB, ALCAR is a version of carnitine which is an essential nutrient in your body. If you became “resistant” to it you would die. So no, it does not need to be cycled. ALCAR is the kind of nootropic that you can dose 3 or 4 times a day for the rest of your life.