Table of Contents
Key Takeaways
- Acetyl-L-Carnitine (ALCAR) is a synthesized version of L-Carnitine that enhances energy production, supports fat burning, and improves cognitive function.
- ALCAR facilitates fatty acid transport to mitochondria, boosts acetylcholine formation, and exhibits antioxidant properties.
- ALCAR benefits brain health by supporting mitochondrial function, protecting brain cells, and improving cerebral blood circulation.
- It has potential therapeutic effects on conditions such as Alzheimer’s, dementia, Parkinson’s, depression, and mild cognitive impairment.
- ALCAR supplementation dosage recommendation is 500 – 1,500 mg per day depending on the desired goal.
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 facilitate fatty acid transport to the mitochondria where they’re needed for producing adenosine triphosphate (ATP). Fatty acid metabolism fuels your cells and can boost physical and mental energy. This also assists with fat burning in other cells.
- 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.
Acetyl-L-Carnitine (ALCAR) 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 supplements are 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. In one animal study, who were given 2 grams of ALCAR daily for 50 days, ALCAR boosted blood levels of ALCAR by 43%.[i]
ALCAR does everything that L-Carnitine does, but by adding an acetyl group, it but can also cross the blood-brain barrier. In another animal study, researchers found that ALCAR supports mitochondrial function which then 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. Test tube studies shows that ALCAR donates a “methyl group” to help make acetylcholine.[iii]
Alzheimer’s-diseased brains show a 25% to 40% reduction in carnitine acetyltransferase, an enzyme that works with L-Carnitine & Acetyl-L-Carnitine.
This enzyme decline led researchers to link low ALCAR with low acetylcholine, and Alzheimer’s onset. They went on to suggest that the therapeutic properties of ALCAR supplementation is a viable therapy for brain regeneration.[iv]
- ALCAR promotes brain energy metabolism 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]
ALCAR is essential for fatty acid oxidation:
- ALCAR shuttles fatty acids into mitochondria, for the creation of ATP.
- ALCAR then shuttles fatty acids out of mitochondria, and flushes out tox ic byproducts.
ALCAR helps maintain mitochondrial function 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 as well as different chronic intermittent stressors. . So ALCAR supplementation 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 cognitive impairment and the neurodegenerative diseases of aging, including Alzheimer’s and dementia.
ALCAR Nootropic benefits
Animal research conducted at 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
One of the most potent Acetyl-L-Carnitine benefits is that it 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 depressive symptoms.[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, have low energy levels, or have Erectile Dysfunction. Within those specific groups, users of Acetyl-L-Carnitine report it helps with memory, mental fatigue, mood, mental performance and the ability to get and maintain an erection.
ALCAR’s brain support and its ability to support 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 quicker thinking.
ALCAR Clinical Research
In one study, researchers showed that ALCAR may have beneficial effects for depression and dementia in the aging brain.[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 receptors 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 for brain function 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?
Carnitine versus androgen administration. 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 hcl 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 sexual 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 may imply that it’s fat-soluble although 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.
ALCAR and thyroid hormones. L-carnitine inhibits both triiodothyronine (T3) and thyroxine (T4) entry into the cell. Which means ALCAR supplementation may make thyroid hormone replacement therapy less effective. But could also help someone suffering from hyperthyroidism.
Types of ALCAR to buy
- Acetyl-L-Carnitine: L-Carnitine with an extra acetyl group. This version of l carnitine is more bioavailable and easily crosses the blood-brain barrier.
- L-Carnitine: This is the standard form of l 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.
Performance Lab Energy contains an effective dose of ALCAR Together, these two help combat diabetes, glucose metabolism, boost energy production, lower high blood pressure, fat metabolism, 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, reducing oxidative stress biomarkers, 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
You can also get 500 mg Acetyl L-Carnitine, 100 mg BioEnhanced™ R-Lipoic Acid, 100 mg CoQ10, 10 mg BioPQQ®, and 2.5 mg BioPerine® in one dose of my favorite energy supplement Performance Lab® Energy.
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 L-Carnitine comes from red meat. And unless you eat a lot of great quality grass-fed beef or mutton you can not produce sufficient amounts, and likely have an Acetyl-L-Carnitine deficiency.
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 geriatric depression. 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 500 mg Acetyl L-Carnitine, 100 mg BioEnhanced™ R-Lipoic Acid, 100 mg CoQ10, 10 mg BioPQQ®, and 2.5 mg BioPerine® 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.
Join The Discussion - 360 comments
Irene
February 4, 2020
Hi David,
My son is autistic and does not tolerate methylated vitamins well (shouting and gets hyper/agitated). I would like to try acetyl l carnitine but wonder if the methyl donor will cause him to react badly. Should I not even bother? thanks for your response.
David Tomen
February 5, 2020
Irene, it’s very possible he’ll react badly to ALCAR too. Maybe try a very small dose of 50 or 100 mg and see what happens first before writing it off entirely.
I’ve not written about autism but have researched it for some consulting clients. Book some time with me if you like and I’ll take you through what I’ve found to work with autism.
Irene
April 23, 2020
Hi again, I ended up trying ALCAR for my 8yo son today – about 75 or 100mg and he seemed to respond well – he did his homework correctly without getting distracted or silly. Thank you so much for your suggestion. My son typically becomes agitated or hyper with ‘calming’ supplements but once he napped after drinking coffee, which was my tipoff that he might react well to ADHD type supplements.
I was wondering what an ‘ideal’ dosage would be and if I should be giving it once or twice a day and if giving it before bedtime would be bad. Thanks for all your wonderful work!!
David Tomen
April 23, 2020
Irene, the “ideal” dosage is whatever works best. We know in general what the dosages are for adults for best results. But for an 8 yr. old it’s much lower and can only be determine by trial and error. Fortunately, ALCAR is non-toxic so the danger in experimenting is minimal.
I’d suggest only AM and at noon for now. I wouldn’t use ALCAR before bed because it may mess with sleep.
Dan
January 25, 2020
Type correction:
Hi David, I really like your blog and thanks for putting all that information out there.
I’ve been suffering from focus, cognition and comprehension all my life. Do you think Mind lab Pro stacked with ALCAR, NALT AND SULBUTIAMINE is safe and enough to fix these issues? I‘m using mindLab Pro, it helps with focus but my comprehension is still really really bad.
I can read the pages of book without understanding anything and had to read it again.
Anything specific to increase comprehension that you can suggest?
David Tomen
January 26, 2020
Dan, you’re on the right track. Now it’s looking for a couple more nootropics to take you to the next step.
Try searching for nootropics that specifically boost short-term and working memory. Take a look at the section “The Molecular Biology of Memory” in this post for some ideas: https://nootropicsexpert.com/best-nootropics-for-learning-and-memory/
Mike Kaminski
January 25, 2020
Hello David I’m so grateful for finding your website! I’d like to ask you a question about ALCAR, can it increase agitation and anxiety?
I’m feeling those effects on myself… Not sure it’s alcar though because I’m taking herbs with it. Second, if I’ll ditch it from my stack will it be a “big loss”?
David Tomen
January 26, 2020
Mike, it’s rare but one of the side effects of ALCAR is increased agitation. It is a cofactor in the synthesis of acetylcholine and helps mitochondria produce ATP by shuttling fatty acids into cells.
I can’t tell you that it’ll be a “big loss” if you ditched it. You’ll need to figure that one out. But if it doesn’t agree with you then you’ll not be able to use it. Are you sure the ALCAR you are using is pure?
Mike Kaminski
January 26, 2020
Not sure unfortunately.
David Tomen
January 26, 2020
Best way to find out is hunt down the manufacturer or vendors website. And see if they’ll provide a Certificate of Analysis. And see if they say anything about how they test product.
If you can’t find that info after locating the vendor I’d find another place to buy it before abandoning it. You need to find a source that is as pure as what they use in Mind Lab Pro and Performance Lab products. One that comes to mind if you want a standalone product is Bulk Supplements.
Mike Kaminski
January 26, 2020
I surely will what is the minimal effective dose? Also can I take it before studying or it has a buildup effect and need to be taken daily?
David Tomen
January 27, 2020
Mike, 500 mg is the minimum effective dose of ALCAR. Reports vary but as far as I can figure out it takes about 3.5 hrs. for the full dose of ALCAR after you take it orally to appear in blood tests. And a half-life of about 15 hours.
So looks like you need to take it at least 3.5 hrs. before studying. And if you take it daily it will have a ‘build-up’ effect. But I imagine only to a certain point and your body will get rid of the excess if you take it daily or 2 – 3-times daily.
Charles
December 2, 2019
Hi David, I made the mistake of ordering just L-Carnitine. Is there anything I can take with it to allow it to have the effects of ALCAR?
Thanks!
David Tomen
December 3, 2019
Charles, there is nothing you can do to make it act like ALCAR. But all is not lost because L-Carnitine is still an effective supplement for your mitochondria. It just cannot cross your blood-brain barrier so does not provide any nootropic benefit. For that you’ll need to get Acetyl L-Carnitine.
wong
October 12, 2019
Hi , David
In your post, you mention about Lipo-Carn®, I can’t seems to find any manufacturer selling this with this registered trademarks on the market
As for Propionyl-L-Carnitine. I cannot find any market selling in this combine form too.
Lastly What do you think of Doctor Best Acetyl_L-Carnitine with Biosint or L- Carnitine Fumarate with Biosint.
Thanks in advance.
David Tomen
October 14, 2019
Wong, it appears that the UK company that makes Lipo-Carn® no longer has a licensee in the USA. But several manufacturers are producing a product containing Propionyl-L-Carnitine. Including the company started by the guy from Smart-Drug-Smarts: https://amzn.to/2MbPDsa.
And Biosint is an Italian company whom I’m not familiar with. But according to their website make several L-Carnitine supplement variations. According to the company, L-Carnitine Fumarate is the “most bioavailable of all carnitine salts” at 58% and best application is for “gel capsules, tablets and soluble granulate sachets”. Looks like it’s worth trying.
M
August 12, 2019
How is stacking this with Aphla-GPC,and say Huperizia [sp?] For vagus nerve/aceytcholine support? [ dry eyes dry mouth, low acetyl type symptoms
David Tomen
August 12, 2019
Alpha GPC + Huperzine-A is fine for acetylcholine support. Just make sure you understand how to dose Huperzine-A: https://nootropicsexpert.com/huperzine-a/
m
August 13, 2019
ty also got a headache from GPC, but my fault i think i took the 300mg doses too close together…
Believe i have some vagus nerve dysfunction according to some symptoms,hoarseness, difficulty swallowing liquids, globulous sensation, constipation,bloating.Ty for huperzia info. And or its anxiety related from long term [PRESCRIBED] ativan and adderall usage [ been off them both 6 months now]
Unsure what sort of long term effects those have on our vagus nerve/brain chemicals…any input?
ty
David Tomen
August 13, 2019
Not sure about Ativan but imagine that it’s harder on the liver than anything else. Long-term Adderall use is rough on synapses and overall neuron health from what I can see from the research. One of the best nootropics for neurogenesis is Lion’s Mane Mushroom because it boosts Nerve Growth Factor and BDNF.
M
August 13, 2019
I’m mainly curious how[long term stimulants/benzo use] as it relates to the vagus nerve, digestion and swallowing/ globulous.The huperzia info was good ty. Just bought a ALCAR/ALA product ,a good combo from what i read
David Tomen
August 14, 2019
Sorry but have not seen anything regarding possible damage done to the vagus nerve or digestion from stimulants or benzo use.
M
August 14, 2019
adderall bad for synapses, acetylcholine occurs there? Vagal tone/function relies partly on Ach? Vagus nerve intervenes with almost everything including the”rest digest” portion of parasympathetic pathway [ i.e vagus nerve]. Frustrating as i know somethings off and the 8 months reading ive done one thing keeps popping up is the vagus nerve. In relation to swallowing and digestion, MMC [migrating motor complex]
I seem to swallow more normal after taking the Alpha GPC, like i’m not swallowing as much air. Also started the ALCAR with it as well.
Appreciate the input ty!
Mompher
September 6, 2020
Is constipation a known side effect of ALCAR? I haven’t changed anything else in my diet or routine and I’ve been taking ALCAR for about 10 days and almost immediately noticed bloating and constipation after starting. I also had this same side effect a couple months ago when I took l-carnitine. Everything I’ve read sys that the different forms of carnitine actually help alleviate constipation. I’ve never read anywhere that it can cause it. Wondering if there is anything I can do to be able to take ALCAR and no have constipation.
David Tomen
September 7, 2020
Clearly you’ve isolated the problem and it’s L-Carnitine in any form that is causing constipation. And no, it’s not a known side effect. But it is a sign that something else is going on in your gut when using it that is out of balance.
Try getting a high quality chelated magnesium supplement. Use 400 mg before bed because it’ll help you sleep. And it should also help relieve the constipation. Natural Stacks MagTech Magnesium is one I’m trying right now and it works really well. Start out with 3 capsules and see if that helps. And double it if necessary. You’ll do your brain a favor and should no longer be constipated: https://amzn.to/3bx8SaQ
Linda
August 1, 2019
Hi Dave,
Great article! I’ve tried taking Acetyl-L-Carnitine several times now and every time it lowers my mood, gives me a headache, and just makes me irritable. I am desperately trying to take the supplements to help mitochondria but cannot seem to tolerate this. I have been trying to find out why I would respond this way and can’t even find a hint, though I have seen some comments from people who have a similar response.
1. Do you have any idea why some people respond this way?
2. Would it be effective to take lysine and methionine instead?
Thank you
David Tomen
August 2, 2019
Linda, ALCAR boosts acetylcholine so it sounds like you are reacting to excess acetylcholine.
You can use a combo of CoQ10 + PQQ along with Alpha Lipoic Acid to support mitochondria. Esp. the first two.
M
August 12, 2019
what is PQQ?
David Tomen
August 12, 2019
https://nootropicsexpert.com/pqq/
Adam
October 29, 2019
I feel this way too at 500mg dose!! But one thing I don’t understand…when I take 300mg alpha gpc and feel good, my brain thanks me when I take 600mg. I feel like Superman at 600mg. I do get a “crash” at 600mg but I also deal with a lot of crashes throughout the day from caffeine, my brain just gets tired often. I’ve been trying to find a good baseline energy without caffeine but can not find one. I was hoping ALCAR would be it… I’ve tried Red Panix Ginseng and Rhodiola with not very good luck, they make me feel very relaxed and have lower energy. I do have ADHD Pi and rx Adderall and Vyvanse(trying to replace them with nootropics)Any input on this David?
David Tomen
October 30, 2019
Adam, I’ve been using prescription Ritalin daily for the last 12 years. Not too long after I started Nootropics Expert I took a one year break from Ritalin and used this stack: https://nootropicsexpert.com/best-nootropics-for-adhd-add/.
And it worked. I could have stayed off of Ritalin permanently but chose not to because this brain needs the extra push.
Part of that protocol is Performance Lab Energy. I suggest you read my review (link in the post) so you understand how it works. It was designed to provide the nutrients needed to fuel mitochondria which is the most basic and fundamental source of all-day-energy. Without the caffeine.
I’ve yet to write a review. But I’ve been using the new Performance Lab Stim which provides caffeine + L-Theanine and it works very well. Better than other stacks like this and likely because of the built-in support from L-Tyrosine and the B-Vitamins.
Tal cohen
July 23, 2019
Hi David,
Is taking ALCAR or any exogenous amino acids on a regular basis can make the body to “forget” to synthesize it by itself or put your body out of “balance”, you think it’s better to minimize there use?
I’ll happy to hear your point of view:)
thank you for your time and this great website with ton of info!!
David Tomen
July 25, 2019
Tal, for the most part we get our amino acids from protein in food. But some are produced in our system. It’s why we use the terms “essential” and non-essential amino acids. We must get essential amino acids from food or a supplement.
As for L-Carnitine, it 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.
Now to answer your question, I’ve never come across anything to suggest taking amino acids as supplements would shut down our body’s builtin amino acid manufacturing system. They need to come from somewhere. As long as you are using recommended dosages I don’t see a problem.
If the supplement takes over, your body will use what you give it. If you suddenly stop, your body will try to get it from somewhere else. Depending on the amino acid – it’ll be from food or within your system. And if it comes up short, something won’t work as well as it should.