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 and into your brain (which L-Carnitine 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 producing adenosine triphosphate (ATP). Fueling your cells and 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.
Table of Contents
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: Helps produce energy within 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 of ALCAR 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 supporting your brain cell’s mitochondria in creating ATP which is your main source of cellular energy.[v]
ALCAR works as a shuttle transport for fatty acids through cell membranes into mitochondria to assist with adenosine triphosphate (ATP) synthesis.[vi]
- As ALCAR shuttles fatty acids into mitochondria, for the creation of ATP.
- As ALCAR shuttles fatty acids out of mitochondria, it flushes out toxic byproducts.
ALCAR helps maintain mitochondrial health 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 benefits
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]
And one animal study conducted in New Delhi showed that Acetyl L-Carnitine reduces lipofuscin in the cerebral cortex, hippocampus, striatum and thalamus.
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.
ALCAR Clinical 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]
ALCAR Recommended Dosage
- 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.
ALCAR 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.
Types of ALCAR to buy
- 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.
- Biosint™ is pharmaceutical grade Acetyl-L-Carnitine that is manufactured in Italy by Sigma Tau HealthSciences
ALCAR 750 mg is also included in the Performance Lab Energy nootropic stack.
Nootropics Expert Recommendation
Acetyl-L-Carnitine 500 – 1,500 mg per day
I 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 you are likely deficient in ALCAR.
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.
I suggest starting with a dose of 500 mg ALCAR daily. ALCAR is a great compliment to a stack including any of the racetams. Take enough Alpha GPC or CDP-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.|
You can also get 750 mg Acetyl L-Carnitine in one dose of my favorite energy supplement Performance Lab® Energy.
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)
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My husband has suffered a TBI. I’m looking into this as a supplement to help him recover. What are your thoughts?
Jessica, you are going to need a lot more than ALCAR for treating TBI. Please see this article for why and what to use: https://nootropicsexpert.com/best-nootropics-for-traumatic-brain-injury/
David, I recently watched your video on ALCAR and wondered if you could comment on its conversion to TMAO; and how to mitigate this.
Thanks,
Wayne
Wayne, it does NOT convert to TMAO and that information is based on headlines from a tiny study in 2013 with 10 people eating red meat. Life Extension has done the best rebuttal in this article which I recommend reading: https://www.lifeextension.com/magazine/2013/8/rebuttal-to-attack-against-carnitine
Wow, will definitely try it. Thank you.
Hi David, after the consumption of 500mg of alcar in the morning I feel a little bit anxious along with racing thoughts. This is an impact of raising noradrenaline or norepinephrine?
Pavlos, even though it rarely happens, the side effects of ALCAR can include nausea, vomiting, increased agitation, weight loss, and restlessness. If you are experiencing anxiety and racing thoughts then ALCAR is the wrong supplement for you.
Hi David,
I take alcar and r-ala. Could this combination have a negative effect on cellular uptake of thyroid hormone and if so would this be significant enough for me to worry about? If it’s only a slight effect then I’d rather keep taking them.
Howard, ALCAR can affect thyroid hormones. I use ALCAR and am hypothyroid so need to be careful about how much I use or I can go hypo.
Thanks David,
I’ll be careful with dosage and keep monitoring the situation.
Hello David! :)))
Stacking ALCAR with fatty acids like MCT or Omega 3 will make them more effective at reaching brain cells?
I’ve seen some guys claiming, ALCAR support fatty acid transport.
Do you personally use it like that? 🙂
Benjamin, ALCAR helps transport fatty acids into mitochondria to be used for the synthesis of ATP. But it’s water soluble and does not need any help crossing into the brain or crossing cell membranes.
David, I want to supplement with Carnitine. I read your list below the different types of Carnitine.
I am looking for a soure of Lipo-Carn.
Im looking to support my body since I have insulin resistance down from diabetes yay me. It took many years to get here. I also have heart flutters which ive had most of my life. I think anything that helps with heart function and possiblly smooth out the rhythm is worth the try.
Also I play pickleball about 15 hours a week. I started this 6 months ago and need to keep as healthy and functioning top shelf. Im 68yr and want to continuing being active for years to come. Thanks for all your responses.
Pilan, if you are 68 it’s going to take a lot more than just Carnitine. See my article on aging here: https://nootropicsexpert.com/best-nootropics-for-the-aging-brain/
The best thing for insulin resistance I’ve found is 500 mg Berberine (https://nootropicsexpert.com/berberine/) 3-times per day.
As for Carnitine, the only form that easily crosses into your brain and is used by the rest of your body is Acetyl L-Carnitine (ALCAR) 500 mg 2 or 3-times per day.
Thank you.
Also is your book a paperback or is it digital only?
Thanks again
Digital-only for this Edition. The 2nd Edition will be offered in hardcover, paperback and digital. Fingers crossed – that should be ready before Christmas.
Niacinamide 500MG capsules. I started with one capsule then 2 so I take 1000MGs twice daily to increase NAD+ levels that naturally decline with age. It’s a B3 precursor found in all of our cells for metabolism.
https://www.sciencedirect.com/science/article/pii/S2468501121000055
I’m 78 years old what dosage of alcar should I use?
Robert, the standard adult dosage is 500 mg 3-times per day. But if that last dose late afternoon interrupts your sleep then stay with two 500 mg doses. Morning and noon.
David,
I’m seriously considering a consultation this coming week.
I just want to point out some of my health issues and want to know if you have any concerns.
1. I have pacemaker now for 2 years. It was installed because of low blood pressure and fainting. I have not had any issues to date.
2. I have a heart ejection factor of 45/50 which is borderline heart failure. My last test was late last year. I have had cardiologist appointment this year and have no issues.
3, I’m 78 years old and generally in good health, I exercise and have a good diet.
4. I have been diagnosed with mild PLMD and use Pregabalin 100 mg to help me stop the kicking and get some sleep at night.
5. I have an extensive vitamins list and trying my best to have the correct approach and want your help.
Please let me know your thoughts
Robert
Robert, I have done consultations with men and women much older then you and with even more serious health issues. I’m happy to help you in any way I can. Schedule the consultation and let’s do this!
David I want to schedule a consultation with you regarding my vitamin stack.b how do I proceed?
Robert here is a link to my calendar: https://calendly.com/davidtomen/60-minute-consultation-with-report. Click that and just follow the steps and instructions through.
David,
Should I send you my list of vitamins that I’m taking that may help facilitate a consultation!
Thank you Robert
Robert, when you schedule the consultation there is space for you to provide a list of the supplement you are using, a list of meds, current health issues and goals or what you wnat to take away from the consultation.