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Acetyl-L-Carnitine Supplements

Acetyl-L-Carnitine Supplements Tested by ConsumerLab.com

Learn how to find the best acetyl-L-carnitine supplements. We purchased and tested the ingredients in acetyl-l-carnitine products and rated their quality. Find out which ones passed our test and why.

Acetyl-L-Carnitine Supplements Review

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CL Answer

Does Procera AVH really improve memory and mood?

Procera AVH information, including evidence from clinical studies on memory, cognition, mood, safety, and a lawsuit.

CL Answer

Does Qualia Mind boost memory and mental function and is it worth cost?

Learn about the ingredients in Qualia Mind, whether or not we think the formula works and is safe, and if we think it's worth the cost.

qualia-mind

CL Answer

Is there a danger in taking lecithin or phosphatidylcholine? I heard that they may increase the risk of heart attacks.

Lecithin, phosphatidylcholine and choline - Learn more about the potential link between them and cardiovascular disease.

Increased Heart Risk

Clinical Update

8/28/2020

Acetyl-L-carnitine + Alpha-Lipoic Acid for Lowering Blood Pressure?

We were recently asked if taking a combination of acetyl-L-carnitine and alpha-lipoic acid can help lower blood pressure. Find out what research shows in the What It Does section of the Acetyl-L-Carnitine Supplements Review. Also see our answer to the question: Which supplements can help to lower blood pressure?

CL Answer

What is Pycnogenol, does it work, and is it the same as other pine bark extracts?

Learn more about Pycnogenol, including evidence from clinical studies on blood clots, osteoarthritis, cognition, vision, tinnitus, and the skin and safety.

Pycnogenol Health Benefits -- woman with leg pain

CL Answer

Which supplements help with erectile dysfunction?

Supplements for erectile dysfunction. Find out which supplements can help with ED, including ginseng, L-arginine, and maca.

Man in Grey Tee Holding Water and White Supplement

CL Answer

What is Brain Bright and can it really improve memory or cognition?

Learn more about BrainBright, including clinical studies on memory and cognition, safety, and cost.

CL Answer

Are supplements such as Thyroid Care Plus helpful for hypothyroidism? Can supplements worsen thyroid function? And what is nascent iodine?

Learn about supplement ingredients such as iodine, selenium, zinc, acetyl-l-carnitine, ashwagandha and guggul used for thyroid conditions and find out if they are beneficial. Also learn why ingredients such as alpha-lipoic acid, soy, resveratrol, quercetin may impair thyroid function.

Woman holding various vitamins and supplements in one hand and glass of water in the other

Clinical Update

4/14/2013

Concern Over Carnitine Causing Cardiovascular Disease

Intake of L-carnitine from supplements (and from red meat) may foster atherosclerosis (hardening of the arteries), according to new research. Once ingested, L-carnitine is converted in some people to a compound which reduces the normal clearing of cholesterol from arteries.

For more details, see the updated reviews of B Vitamin Supplements & Energy Drinks and Protein Powders, as some of these products contain L-carnitine. The Acetyl-L-Carnitine Supplements review has also been updated because acetyl-L-carnitine is chemically similar to L-carnitine, suggesting a potential concern.

CL Answer

Which supplements or foods can help lower cholesterol and keep my heart healthy? Are there any to avoid?

Information about heart health supplements & vitamins that help with cholesterol, including sterol esters, CoQ10, and vitamin D, and which may be bad for the heart, like calcium.

Product Review

Ginkgo (Ginkgo Biloba) Supplements Review

Choose the Best Ginkgo Biloba Supplement. Finding Real Ginkgo Isn't Easy — 60% Fail ConsumerLab's Tests of Quality.

Ginkgo Biloba Supplements Tested by ConsumerLab.com

CL Answer

Do any supplements, like Nervive, help with nerve pain, like sciatica, diabetic neuropathy or postherpetic neuralgia?

Find out which supplements for nerve pain, including fish oil and alpha-lipoic acid, are effective for sciatica, diabetic neuropathy, or postherpetic neuralgia.

CL Answer

Body Odor: Supplements & Foods That May Help, or Make It Worse

Some people with adequate personal hygiene still experience body odor. Learn if taking supplements such as activated charcoal, champignon extract, copper chlorophyllin, L-carnitine, N-acetyl cysteine (NAC), or other ingredients might help or make body odor worse.

Woman holding her nose and pointing to a man with body odor

CL Answer

Can any supplements improve or worsen symptoms of fibromyalgia?

Find out if any supplements may help improve fibromyalgia symptoms, learn which supplements do not seem beneficial, and find out if any supplements worsen symptoms.

Woman holding sore back

News Release

March 11, 2019

Best NAC (N-acetyl cysteine) Supplements Identified by ConsumerLab

White Plains, New York, March 11, 2019 — NAC (N-acetyl cysteine) supplements are promoted for many uses, including "liver support," "immune support," and reducing symptoms of the flu and flare-ups of chronic bronchitis.

News Release

December 09, 2014

Round-up of Recent Product Tests by ConsumerLab.com -- Results for B Vitamin Supplements & Energy Drinks, Garlic, NAC (N-acetyl cysteine), Iron and Omega-7 Fatty Acids

White Plains, New York, December 9, 2014 — In recent months, ConsumerLab.com has published test results for a variety of popular supplements, including B vitamins supplements and energy drinks, NAC (N-acetyl cysteine), iron and garlic. In addition, ConsumerLab.

CL Answer

I take levothyroxine (Synthroid), a thyroid hormone to treat hypothyroidism. Are there supplements or foods I should avoid, or be taking, due to this drug?

Is taking certain supplements and hypothyroidism medications bad? Learn which supplements can interact with thyroid hormone medications like levothyroxine (Synthroid), thyroid hormone levels, and laboratory tests.

Levothyroxine (Synthroid) Supplement Interactions

CL Answer

Do any supplements, foods or lifestyle modifications help with brain function, like memory and cognition?

Find out which supplements help improve memory, brain function and cognition, including fish oil, some B vitamins, cocoa, and curcumin. ConsumerLab's answer explains the evidence for supplements promoted to help with brain function and cognition.

Supplements for Memory -- doctor holding a model of a brain and fish oil capsule

CL Answer

Are L-carnosine supplements helpful and safe?

Learn about the potential health benefits of L-carnosine, as well as possible safety concerns, drug interactions and cost.

Capsules with white powder and spoon holding white powder on white background

CL Answer

Do any supplements reduce the side effects of chemotherapy? Should any be avoided?

Find out if there are any supplements that can help with the side effects of chemotherapy, such as nausea, vomiting, diarrhea, nerve damage and others. ConsumerLab.com's answer explains.

Supplements & Chemotherapy Side Effects -- chemotherapy medicine and capsules

Clinical Update

1/28/2018

L-Carnitine Caution

A study in which L-carnitine was given to women during chemotherapy had a surprising result: It worsened side effects. Get the details in the Concerns and Cautions section of the Acetyl-L-Carnitine Supplements Review.

Clinical Update

12/02/2018

Carnitine Heart Risk?

Supplementing with L-carnitine can raise blood levels of TMAO which can potentially advance atherosclerosis. However, the science is not clear, as suggested by a recent study. Get the details in the L-Carnitine section of the Acetyl-L-Carnitine Supplements Review.

Clinical Update

9/28/2021

Supplements During Chemotherapy?

If you are getting chemotherapy, experts now recommend avoiding acetyl-L-carnitine. Also, see what they have to say about using alpha-lipoic acid, vitamin B-12 and vitamin E.

Clinical Update

4/08/2022

Cardiovascular Concerns With L-Carnitine

L-carnitine supplementation may have negative cardiovascular effects, according to a recent study. Get the details in the Concerns and Cautions section of our Acetyl -L-Carnitine Review.

Clinical Update

6/21/2022

Best Form of Carnitine?

Which form of L-carnitine is best absorbed? Find out what research shows in the What to Consider When Buying section of our Acetyl-L-Carnitine Supplements Review.

CL Answer

What are "broad-spectrum micronutrient" supplements, and do they have greater health benefits than multivitamin/multimineral supplements?

Learn about "broad-spectrum micronutrients" and how they compare to multivitamin/multimineral supplements.

Multivitamins on a table with a multivitamin supplement nutrition label in front of the multivitamins

CL Answer

Which supplements reduce hearing loss?

Can supplements such as alpha-lipoic acid, magnesium, N-acetyl-cysteine, folate or vitamins B-12, C and/or E help prevent or improve symptoms among people with hearing loss due to excessive noise or aging? Find out what the clinical evidence shows, and learn whether Advanced Hearing Formula, a supplement marketed for ear health, is likely to help.

Older man holding his hand up to his ear due to hearing loss

Product Review

Huperzine A Supplements Review

Choose the Best Huperzine A Supplement. CL Tests Reveal the Best Huperzine A Supplements for Memory.

Huperzine A Supplements Tested by ConsumerLab.com

Recalls & Warnings

January 19, 2022

FDA Warns Seller of Carnitine and Alpha Lipoic Acid Supplements

On November 18, 2021, the FDA issued a warning letter to GeroNova Research Inc.

Product Review

Weight Loss Supplements Review (7-Keto DHEA, Forskolin and Stimulant Blend Supplements)

Choose the Best Weight Loss Supplement. Be Careful With Weight Loss Supplements — Few Pass Quality Testing and Safety Review.

Weight Loss Supplements Tested by ConsumerLab.com

Product Review

Alpha Lipoic Acid Supplements Review

Choose the Best Alpha-Lipoic Acid Supplement — See the Amounts of Active "R-Isomer" We Found

CL Answer

Which supplements can help to lower blood pressure?

Supplements to lower blood pressure, including CoQ10, vitamin C, fish oil, and olive oil, are all explored to find out what works.

Supplements that can lower, or raise blood pressure -- blood pressure cuff and bottle of pills

News Release

November 18, 2008

Adulteration Suspected with Some "Memory" Supplements -- Few Ginkgo and Huperzine Supplements Pass ConsumerLab.com Tests; Quality High for Acetyl-L-Carnitine

WHITE PLAINS, NEW YORK — NOVEMBER 18, 2008 — Tests by ConsumerLab.com of Ginkgo biloba supplements show that few products meet quality standards.

CL Answer

If I buy NAC as a loose powder in a large bag, as opposed to in tablet or capsule form, will it spoil? I've heard it can spoil or degrade into a harmful by-product.

Learn more about the different forms of N-Acetyl-Cysteine (NAC), including whether or not powder will spoil faster than tablets.

N-acetyl cysteine (NAC) supplements tested by ConsumerLab.com

News Release

October 28, 2008

Tests reveal quality problems with vitamin A supplements -- New ConsumerLab.com report focuses on vitamin A, including beta-carotene and cod liver oil

WHITE PLAINS, NEW YORK — OCTOBER 28, 2008 — ConsumerLab.com is cautioning that the amount vitamin A in some supplements may be much higher or lower than the amount stated on labels. Among ten supplements recently selected for testing, ConsumerLab.

Recalls & Warnings

September 10, 2013

CoQ10 and Carnitine Supplement Company Warned For Manufacturing Violations

On April 15, 2013, the FDA issued a warning letter to Irenda Corporation, following a facility inspection which found the company's products, including L-Carnitine, Acetyl L-Carnitine, and Co-Q 10 with L-Carnitine, to be adulterated because they were packed, or held under conditions that violate ...

Recalls & Warnings

September 10, 2012

Maker of Concussion Recovery Supplement Warned For Making Drug Claims

On August 28, 2012, the FDA issued a warning letter to Trinity Sports Group, Inc. after a review of the company's websites found statements about Neuro Impact Concussion Response Formula constituted drug claims not permitted on supplements. 

News Release

October 02, 2008

ConsumerLab.com finds melatonin supplements range in strength but ingredient quality is high

WHITE PLAINS, NEW YORK — OCTOBER 2, 2008 — ConsumerLab.com announced test results today from its new Product Review of Melatonin Supplements.  Melatonin supplements may help treat certain sleep disorders and disturbances, including jet lag.

News Release

September 17, 2008

ConsumerLab.com's tests of menopause supplements reveal wide range in strength and quality; mislabeling and contamination discovered -- Soy and red clover isoflavones, black cohosh, and progesterone products tested

WHITE PLAINS, NY — September 17, 2008 — Risks associated with traditional hormone therapy for symptoms of menopause have increased public interest in alternative treatments, particularly dietary supplements. But a report today of recent tests by ConsumerLab.

News Release

August 12, 2008

ConsumerLab.com finds improvements in labeling of nutrition bars but potential pitfalls exist -- New report compares 20 bars, including those for protein, fiber, energy and whole food

WHITE PLAINS, NY — August 12, 2008 — Labeling on nutrition bars has become more accurate, according to a new report by ConsumerLab.com.

Clinical Update

1/21/2022

Seller of Carnitine and Alpha Lipoic Acid Warned by FDA

FDA Warns Seller of Carnitine and Alpha Lipoic Acid

Recalls & Warnings

September 05, 2014

Seller of "Nerve", "Cleanse" and Probiotic Supplements Warned for Drug Claims

On July 30, 2014, the FDA issued a warning letter to Plexus Worldwide, Inc., following a review of the company's website and product labels, which found statements made about Fast Relief, BioCleanse and ProBio5 to be drug claims.

Clinical Update

3/26/2016

NAC Reduces Compulsive Picking

A number of studies have shown that N-acetyl cysteine (NAC), a supplement with wide variety of uses, may also reduce compulsive behaviors. The most recent study showed significant improvement in adults with skin picking disorder. Details about this and other studies with NAC, and our ratings of NAC supplements, are found in the N-Acetyl Cysteine Supplements Review >>

Clinical Update

10/14/2022

How Much Zinc Causes Copper Deficiency?

High zinc intake can cause copper deficiency. A CL member asked us how much zinc (from zinc carnitine) would require them to supplement with copper. Find out in our Zinc Carnosine article and learn more in the Concerns and Cautions section of our Zinc Supplements Review, which also lists food sources of copper.

Recalls & Warnings

May 07, 2012

FDA Warns Doctor Promoting Own Supplements Online as Treatments

On April 18, 2012 the U.S. Food and Drug Administration (FDA) sent a Warning Letter to Jacob Teitelbaum, M.D. of Fatigued to Fantastic, LLC regarding the promotion that company's products on its website www.endfatigue.com.

News Release

January 25, 2006

Sexual enhancement supplements analyzed by Consumerlab.com

WESTCHESTER COUNTY, NEW YORK — JANUARY 25, 2006 — ConsumerLab.com announced today that it found only six out of eleven supplements used for sexual enhancement to contain key ingredients listed on their labels and meet other quality criteria.

News Release

January 03, 2006

Tests of memory enhancing supplements by ConsumerLab.com reveals lead in some ginkgo

WESTCHESTER COUNTY, NEW YORK — TUESDAY, JANUARY 3, 2006 — In its new test report on Memory Enhancement Supplements, ConsumerLab.com has revealed finding significant amounts of lead in certain products on the market.

Recalls & Warnings

March 13, 2013

Liquid Supplements Not Properly Manufactured Despite Certification

On February 22, 2013, the FDA issued a warning letter to Organics Corporation of America, dba Ambix Laboratories, following a facility inspection which found the company's dietary supplements Baby Plex Vitamin Drops, Carnitine Liquid, and Optimal Nutritional Liquid to be adulterated because they ...

Recalls & Warnings

September 07, 2002

FDA Sends Warning Letters to Seven Online Supplement Sellers For Therapeutic Claims

On August 27, 2002, the FDA posted seven "Cyber" letters recently issued from its Center for Food Safety and Applied Nutrition (CFSAN) to internet website operators promoting dietary supplement products that claim to diagnose, mitigate, treat, cure, or prevent a specific disease or class of ...

Recalls & Warnings

August 20, 2013

Weight Loss Supplement Formulas For Men and Women Recalled Due To Undeclared Drugs

On August 16, 2013, Herbal Give Care LLC issued a voluntary recall of all lots of weight loss dietary supplements Esbelder man, Esbelder fem and Esbelder siloutte because they were found to contain the undeclared drugs sibutramine, N-desmethylsibutramine, and N-di-desmethylsibutramine.

Recalls & Warnings

July 23, 2013

Weight Loss Supplements Containing Undeclared Drugs Recalled

On July 19, 2013, Herbal Give Care LLC issued a voluntary recall of all lots of weight loss supplements Esbelin siloutte te and Esbelin siloutte Herbal Blend with L-Carnitine because they were found to contain undeclared sibutramine, N-desmethylsibutramine, and N-di-desmethylsibutramine.

Recalls & Warnings

November 18, 2011

FDA Warns Maker of Milk Thistle and L-Carnitine Supplements of Serious Violations

The U.S. FDA posted a Warning Letter to CJ Labs (Miami, Florida) dated November 1, 2011 regarding serious violations of Good Manufacting Practices in the production of its Milk Thistle and L-Carnitine supplements.

Recalls & Warnings

February 13, 2013

FDA Warns Maker of Weight Loss and Whey Protein Supplements For Manufacturing Violations and Misbranding

January 25, 2013, the FDA issued a warning letter to dietary supplement manufacturer SciLabs Nutraceuticals, following a facility inspection which found the company's dietary supplements and supplement ingredients, including N-Large 2, Flo-Gard AB, Nitrogen Glutamine capsules, Nutritech nutritional ...

Recalls & Warnings

March 06, 2015

FDA Warns Consumers Not to Buy or Use Weight Loss Supplement Containing Hidden Drug

On March 5, 2015, the FDA warned consumers not to buy or use weight loss supplement L-Carnitine Sob Strengthening Version Slimming Miracle Capsule because it was found to contain sibutramine.

Recalls & Warnings

August 29, 2013

Seller of CELLFOOD Supplements Warned For Manufacturing Violations and Drug Claims

On August 1, 2013, the FDA issued a warning letter to supplement retailer Lumina Health Products, Inc.

Recalls & Warnings

January 21, 2017

Seller of "Cancer Kits," Alpha Lipoic Acid Supplements and More Warned for Drug Claims

On December 22, 2016, the FDA issued a warning letter to Northern Health Products, Inc. following a review of the company's websites, www.northernhealthproducts.com and www.petdca.