Acetyl L–Carnitine

October 3, 2020

This article provides general nutrition information only and is not medical advice.

Overview

In the body, acetyl-L-carnitine is made from L-carnitine that the body produces naturally. L-carnitine is an amino acid. Amino acids are usually used as building blocks for proteins, but L-carnitine is not. Instead, L-carnitine and acetyl-L-carnitine are used to help the body turn fat into energy.

People take acetyl-L-carnitine by mouth for improving memory and thinking skills, alcohol use imbalance, bipolar imbalance, nerve pain, fibromyalgia, infertility, and many other conditions, but there is no good scientific evidence to support these uses.

The body can convert L-carnitine to acetyl-L-carnitine and vice versa. But no one knows whether the effects of acetyl-L-carnitine are from the chemical itself, from the L-carnitine it can make, or from some other chemical made along the way. For now, don't substitute one form of carnitine for another.

Classification

Is a Form of:

Amino acid

Primary Functions:

Memory and thinking skills, alcohol use imbalance

Also Known As:

Acetil-L-Carnitina, Acetyl Carnitine, Acétyl Carnitine, Acetyl L-Carnitine

How Does It Work?

Acetyl-L-carnitine helps the body produce energy. It is important for heart and brain function, muscle movement, and many other body processes.

Uses

Decline in memory and thinking skills that occurs normally with age. Taking acetyl-L-carnitine improves memory and mental function in older people with some memory loss.
Tiredness in older adults. Taking acetyl-L-carnitine improves feelings of mental and physical tiredness in older people. It also appears to reduce feelings of tiredness after exercise.
Low levels of testosterone in older men. Taking acetyl-L-carnitine by mouth along with propionyl-L-carnitine seems to help concerns related to declining male hormone levels. This combination taken for 6 months seems to improve sexual dysfunction, low mood, and fatigue in much the same way the male hormone testosterone does.
Alcohol use imbalance. When given intravenously (by IV) for 10 days then taken by mouth for 80 days, acetyl-L-carnitine helps reduce withdrawal concerns and increase the amount of time before another alcoholic drink is consumed. However, most of the concerns improvement occurs during the first week. Therefore, it's not clear if taking acetyl-L-carnitine by mouth offers further benefit following IV nutritional support.
Alzheimer condition. Acetyl-L-carnitine might slow the rate of condition progression, improve memory, and improve some measures of mental function and behavior in some patients with Alzheimer condition. It is more likely to help those with early-onset Alzheimer condition who are less than 66 years of age and have a faster rate of condition progression and mental decline.
Decline in memory and thinking skills in older people that is more than what is normal for their age. Taking acetyl-L-carnitine seems to improve memory in 30-60 year-old people with long-term thinking problems due to alcohol use.
Low mood. Taking 1-4 grams of acetyl-L-carnitine per day seems to improve mood and decrease low mood in some people. It seems to work better in elderly people and when taken in higher amounts.
Nerve pain in people with diabetes (diabetic neuropathy). Taking acetyl-L-carnitine seems to improve concerns in people with nerve pain caused by diabetes. Acetyl-L-carnitine seems to work best in people who have not had diabetes for a long time and those who have poorly controlled diabetes. Doses of 1000 mg taken two or three times daily seems to work better than smaller doses.
Conditions in a man that prevent him from getting a woman pregnant within a year of trying to conceive (male infertility). Taking acetyl-L-carnitine by mouth, usually along with L-carnitine and other supplements, seems to increase sperm motion and may increase pregnancy rates.
A condition that causes curved, painful erections (Peyronie condition). Acetyl-L-carnitine seems to be more effective than a drug called tamoxifen for reducing pain and slowing worsening of Peyronie condition.

Recommended Dosing

The following doses have been studied in scientific research:

ADULTS

BY MOUTH:

For decline in memory and thinking skills that occurs normally with age: 1500-2000 mg of acetyl-L-carnitine has been used daily for 3 months.
For tiredness in older adults: 2 grams of acetyl-L-carnitine has been used twice daily for 180 days.
For low levels of testosterone in older men: 2 grams of acetyl-L-carnitine plus 2 grams of propionyl-L-carnitine has been used daily for 6 months.
For alcohol use imbalance: 1-3 grams of acetyl-L-carnitine has been administered intravenously (by IV) for 10 days. Then for the next 80 days, 3 grams of acetyl-L-carnitine has been taken by mouth daily.
For Alzheimer condition: 1500-3000 mg of acetyl-L-carnitine has been taken by mouth daily in two or three divided doses for 3-12 months.
For decline in memory and thinking skills in older people that is more than what is normal for their age: 2 grams of acetyl-L-carnitine has been used daily for 90 days.
For low mood: 1-4 grams of acetyl-L-carnitine has been used daily for up to 60 days. Higher doses seem to have the greatest effect.
For nerve pain in people with diabetes (diabetic neuropathy): 1500-3000 mg of acetyl-L-carnitine has been taken by mouth daily in divided doses for up to one year. In some cases, 1000 mg of acetyl-L-carnitine was injected into the muscles for 10-15 days before it was taken by mouth.

For conditions in a man that prevent him from getting a woman pregnant within a year of trying to conceive (male infertility):

1 gram of acetyl-L-carnitine plus 2 grams of L-carnitine has been taken daily to support male infertility
For male infertility secondary to abacterial prostatovesiculoepididymitis: 500 mg of acetyl-L-carnitine plus 1 gram of L-carnitine every 12 hours has been used following 2 months of nutritional support with nonsteroidal joint comfort drugs (NSAIDs).
For male infertility due to low sperm movement: A combination containing 1660 mg of L-arginine, 150 mg of L-carnitine, 50 mg of acetyl-L-carnitine, and 200 mg of Panax ginseng has been taken daily for 3 months.
For male infertility due to prostate swelling caused by Chlamydia immune challenge: combination containing 1660 mg of L-arginine, 150 mg of L-carnitine, 50 mg of acetyl-L-carnitine, and 200 mg of Panax ginseng daily for 6 months along with 600 mg of prulifloxacin.
For male infertility with low sperm numbers, low sperm movement, and abnormally shaped sperm (oligoasthenozoospermia): A specific product (Proxeed Plus, Alfasigma USA) containing L-carnitine 1 gram and acetyl-L-carnitine 0.5 gram, with citric acid, zinc, coenzyme Q10, selenium, vitamin C, folic acid, and vitamin B12, twice daily for 6 months.

For a condition that causes curved, painful erections (Peyronie condition): 1 gram of acetyl-L-carnitine has been taken twice daily for 3 months.

BY IV:

For alcohol use imbalance: 1-3 grams of acetyl-L-carnitine has been given by IV over 3-4 hours for 10 days. Thereafter, 3 grams of acetyl-L-carnitine has been taken by mouth daily for 80 days.

AS A SHOT:

For nerve pain in people with diabetes (diabetic neuropathy): 1000 mg of acetyl-L-carnitine has been given as a shot daily for 10-15 days. In some cases, 2000 mg of acetyl-L-carnitine has been taken by mouth daily for 12 months following the shots.

Acetyl – L – Carnitine Supplements Frequently Asked Questions

What is acetyl L carnitine good for?

Acetyl-L-carnitine is used for a variety of mental imbalances including Alzheimer's condition, age-related memory loss, late-life low mood, thinking problems related to alcoholism, thinking problems related to Lyme condition, and thinking problems related to very poor liver function (hepatic encephalopathy).

Can you take acetyl L carnitine everyday?

For low mood: 1-4 grams of acetyl-L-carnitine has been used daily for up to 60 days. Higher doses seem to have the greatest effect. For nerve pain in people with diabetes (diabetic neuropathy): 1500-3000 mg of acetyl-L-carnitine has been taken by mouth daily in divided doses for up to one year.

What are the side effects of acetyl L carnitine?

People taking carnitine have reported a number of side effects, including:

Diarrhea, nausea, stomach pain, and vomiting.
Trouble sleeping.
Higher cardiovascular health.
Lower blood sugar and higher triglycerides (in people with diabetes)
Psychosis (in people with bipolar imbalance)

What is the best brand of acetyl L carnitine?

Choose the Best Acetyl-L-Carnitine Supplement

Bluebonnet Acetyl-L-Carnitine.
Doctor's Best Best Acetyl-L-Carnitine.
GNC Acetyl L-Carnitine.
Jarrow Formulas Acetyl L-Carnitine.
Twinlab Acetyl-L-Carnitine.
Vitacost Acetyl-L-Carnitine.
Vitamin Shoppe Acetyl-L-Carnitine.

Does acetyl L carnitine help you lose weight?

Fat-loss Effects: It shuttles fuel (in the form of long chain fatty acids) to your muscle mitochondria (read more about Carnitine Shuttle here), which increases your energy production and can increase endurance. Acetyl-L-carnitine also encourages your metabolism to burn more fat while you work out.

Can you take acetyl L carnitine at night?

acetyl-L-carnitine (ALCAR) at bedtime after a 3-4 hour fast. The dose of ornithine controls the amount of GH produced. Food eaten before the dosage cancels the effect. This technique has been tested in humans and only works at night..

What is the best time to take L carnitine?

Because L-carnitine can be absorbed quickly into the body, especially when it's consumed in liquid form, the best time to take is in the morning and/or prior to workouts. It is recommended that you take between 2-4g of L-carnitine per day, divided into two or three evenly split dosages.

Does acetyl L carnitine raise cardiovascular health?

ALCAR is a promising supplement in controlling cardiovascular health. It's safe, cheap, and well-tolerated by most people. Although not much research has been done supporting its use for high cardiovascular health, one small study suggested that it may help reduce systolic cardiovascular health.

How long does acetyl L carnitine take to work?

When given intravenously (by IV) for 10 days then taken by mouth for 80 days, acetyl-L-carnitine helps reduce withdrawal concerns and increase the amount of time before another alcoholic drink is consumed. However, most of the concerns improvement occurs during the first week.

How much acetyl L carnitine should I take a day?

The standard dose of L-carnitine is 500–2,000 mg per day. Although dosage varies from study to study, here is an overview of the use and dose for each form: Acetyl-L-carnitine: This form is best for brain health and function. Doses vary from 600–2,500 mg per day.

Should acetyl L carnitine be taken with or without food?

Acetyl-L-carnitine may be taken with or without food. Acetyl-L-carnitine should be taken immediately after removing it from the blister package.

Does acetyl L carnitine lower lipid balance?

Acetyl-L-carnitine supplementation restores decreased tissue carnitine levels and impaired lipid metabolism in aged rats. ... ALCAR nutritional support decreased all lipoprotein fractions and consequently the levels of triacylglycerol and lipid balance.

Does acetyl L carnitine help neuropathy?

Acetyl-L-carnitine (ALC), a naturally occurring amino acid, may be an ideal wellbeing agent to address this otherwise recalcitrant condition. ALC is potentially effective at preventing peripheral neuropathy as well as lessening neuropathic concerns once they have developed.

Does Acetyl l carnitine cause atherosclerosis?

Get the details in the Concerns and Cautions section of the Acetyl-L-Carnitine Supplements Review. Concern Over Carnitine Causing Cardiovascular condition -- (4/14/2013) Intake of L-carnitine from supplements (and from red meat) may foster atherosclerosis (hardening of the arteries), according to new research.

Does acetyl L carnitine increase dopamine?

We studied the effect of acetyl-L-carnitine (ALCAR) on dopamine release and the effect of long-term acetyl-L-carnitine nutritional support on age-related changes in striatal dopamine receptors and brain amino acid levels. Acetyl-L-carnitine lessened the reduction in the level of taurine only in the striatum.

Does acetyl L carnitine make you tired?

Fatigue is a common concerns in people with multiple sclerosis. But the cause of the fatigue isn't well-understood. As for treating fatigue with acetyl-L-carnitine, some studies have suggested that supplements could ease MS-related fatigue in people with low blood levels of L-carnitine.

Clinical Studies

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