L-carnitine is an amino acid compound used as a supplement to improve mitochondrial health and act as a bioenergetic. In plain English, that means it improves energy levels by boosting the action of the mitochondria -- the energy powerhouse in your cells.
L-carnitine has a range of sub-compounds that can have a variety of different effects. The supplement may help improve cognition and aid in recovery. It also acts as a nitric-oxide-boosting ingredient that may improve your workouts.
Carnitine acts as an antioxidant, making it a possible treatment for a variety of different health problems. Antioxidants help eliminate free radicals, which damage cells and can alter DNA. Experts theorize that since antioxidants neutralize free radicals, L-carnitine may reduce or prevent health problems.
How it works
L-carnitine works by making it easier for the body, specifically the mitochondria in your cells, to produce more energy. This leads to improved endurance, which in turn may yield better performance at the gym and increased overall activity.
This amino acid does have a relatively low bioavailability, however, with just about 15% staying intact. The remaining useable form will pass through your digestive system. Despite its low absorption rate, L-carnitine and its sub-compounds still provide several benefits.
In the body, L-carnitine is converted into a variety of related compounds. Each has different benefits. While you could supplement with a broad-range L-carnitine supplement, read about the specific benefits provided by sub-compounds, like acetyl L-carnitine, propionyl L-carnitine, and L-carnitine L-tartrate.
Acetyl L-carnitine, or ALCAR, acts as a neurotransmitter and can help with problems related to aging, especially brain cognition. The energy-boosting effect of ALCAR also promotes endurance and increases alertness, though the effect is not as strong as caffeine.
ALCAR is recommended for offsetting the effects of chronic fatigue, metabolic disorders, and dementia.
Endurance athletes considering l-carnitine supplementation should skip right to ALCAR. The fatigue-fighting effects (which are discussed in depth on our acetyl l-carnitine page) are well worth their price, especially when considering the focus boost that comes along with it.
Propionyl-L-carnitine, or PLCAR, is estimated to have a somewhat higher bioavailability than standard L-carnitine, but no studies quantify how much. It also has fewer side effects than other L-carnitine sub-compounds.
Propionyl-L-carnitine increases energy production in the muscle by converting fatty acids to acylcarnitines, which are burned as energy, resulting in weight loss. This process allows you to retain lean muscle mass since the body only burns fat, not muscle. You should note, however, that studies on weight loss using propionyl-L-carnitine has only been studied on mice, not humans.
L-carnitine L-tartrate, or LCLT, is a great supplement for recovery following a workout. Supplemental LCLT acts as an antioxidant, lowering free radical production, and can reduce soreness after exercise. In one small study, researchers demonstrated that using 2g of LCLT daily reduced muscle disruption following exercise up to 45% faster compared to a placebo group.
To help build endurance and get the most out of your workout, glycine propionyl-L-carnitine (GPLC) is extremely beneficial. It helps promote nitric oxide in your body, which in turn acts as a vasodilator. In plain language, it increases blood flow and oxygen supplied to your muscles.
Standard L-carnitine is the most widely available and least expensive of all the carnitine compounds. Each are available in liquid, powder, and capsules. Liquid forms provide faster uptake and more of the compound can be absorbed. However, liquid, as well as powders, can have a bitter aftertaste, making the pill form more appealing to some.
The recommended dosage range for supplements in the L-carnitine family are as follows:
|L-Carnitine Compound||Recommended Dosage (mg p/d)||Recommended Dosage (g p/d)|
|Standard||1,000mg to 3,000mg||1g to 3g|
| ALCAR ||630mg to 2,500mg||.63g to 2.5g|
|PLCAR||500mg to 2,000mg||.5g to 2.g|
| LCLT ||1,000mg to 4,000mg||1g to 4g|
| GPLC ||1,000mg to 4,000mg||1g to 4g|
According to the University of Maryland Medical Center, a typical dose for standard L-carnitine is between 1g to 3g per day.
Who should take it
It's hard to imagine a group that this supplement would put at a disadvantage. By helping you stay active or improving your performance, it's an excellent supplement for anyone interested in healthy living. It's especially beneficial if you suffer from chronic fatigue or age-related neurological problems.
In 2011, researchers from Maryland's Institute of Chronic Illnesses concluded that L-carnitine therapy, administered at 50mg/kg of bodyweight per day for three months, demonstrated significant improvement in clinical measurements of autism spectrum disorder severity. More studies are needed to confirm these results and move towards autism treatment methods using this amino acid.
Although its supplementation is popular for weight loss, standard l-carnitine is not shown to burn fat — even when combined with aerobic activity. Due to the lack of fat burning effects, we consider this a third-tier supplement for most individuals, and typically recommend one of the sub-compounds, such as acetyl-l-carnitine. In 2005, Swiss exercise physiology experts demonstrated that the compound does not improve recovery from fatigue-inducing workouts.
According to the University of Maryland Medical Center, L-carnitine is safe for use in combating fatigue and improving exercise performance, "but may not help much."
Potential side effects
Taking too much L-carnitine, about 5g, can cause digestive upset, abdominal pain, vomiting, and diarrhea, though these symptoms cease once you lower your dosage (start by cutting it in half), or stop taking it completely. Another good idea is to switch to a sub-compound such as ALCAR, which requires you to take less, and may yield fewer problems.
Other side effects include rash, body odor, and increased appetite, though these are rare.
As with any medication or supplement, talk to your doctor before changing or adding to your fitness regimen. If you have any of the following disorders, delay any type of carnitine supplementation until you consult with a physician:
By helping you stay active and improving your performance, L-carnitine is an excellent supplement for anyone interested in healthy living.
- Peripheral vascular disease
- High blood pressure
- Liver disease from alcoholism (cirrhosis)
- Kidney disease
- History of seizures
Red meat is the best way of supplementing L-carnitine through diet. It contains 95mg of the amino acid per 100g of beef. That means to get the lowest effective dosage of L-carnitine, at 500mg, you would need to eat more than 526g, or 18.56 oz., of steak every day. If the cost of a 20oz. daily rib eye habit doesn't dissuade you, the possible damage to your arteries and inevitable weight gain should.
We suggest the following brands for liquid and powder L-carnitine formulations:
- NOW Foods has an excellent powdered or capsule L-carnitine supplement in a variety of sizes.
- Dymatize offers a sugar- and calorie-free liquid L-carnitine that is very affordable. Where to buy
- Goo MJ, et. al.; Archives of Pharmacal Research; "Protective effects of acetyl-L-carnitine on neurodegenerative changes in chronic cerebral ischemia models and learning-memory impairment in aged rats;" January 2012
- Mingorance C, et. al.; PLoS One; "Propionyl-L-carnitine corrects metabolic and cardiovascular alterations in diet-induced obese mice and improves liver respiratory chain activity;" March 2012
- Volek JS, et. al.; American Journal of Physiology; "L-Carnitine L-tartrate supplementation favorably affects markers of recovery from exercise stress;" February 2002
- University of Maryland Medical Center; "Carnitine (L-carnitine);" Reviewed March 2011
- Villani RG, et. al.; International Journal of Sports Nutrition and Exercise Metabolism; "L-Carnitine supplementation combined with aerobic training does not promote weight loss in moderately obese women;" June 2000
- Stuessi, C, et. al.; European Journal of Applied Physiology; "L -Carnitine and the recovery from exhaustive endurance exercise: a randomised, double-blind, placebo-controlled trial;" December 2005
- Geier DA, et. al.; Medical Science Monitor; "A prospective double-blind, randomized clinical trial of levocarnitine to treat autism spectrum disorders;" June 2011
L-Carnitine News on PricePlow
Sep 30, 2022 Product News
MuscleSport L-Carnitine Revolution was created.
Aug 22, 2022 Product News
Performix SST Support Burn - L-Carnitine was created.
Jul 29, 2022 Blog Post
5% Nutrition Liquid L-Carnitine 3150: The Rich Piana of Carnitine Supplements
With a quadfecta of L-Carnitine, ALCAR, LCLT, & GPLC with GBB / Thiamin, 5% Nutrition's Liquid L-Carnitine is the Rich Piana of carnitine supplements!
Jul 16, 2022 Product News
Pro Supps L-Carnitine 3000 has new variations: L-Carnitine
Jul 10, 2022 Product News
PEScience TruCarnitine was created.
Jul 08, 2022 Product News
VMI Sports L-Carnitine 3000 has new variations: L-Carnitine
Jun 22, 2022 Product News
KAL Acetyl-L-Carnitine was created.
Category: Acetyl L-Carnitine
Jun 16, 2022 Product News
KAL Acetyl-l-Carnitine Alpha Lipoic Acid was created.
Categories: Acetyl L-Carnitine, Alpha Lipoic Acid
May 08, 2022 Product News
Beyond Raw Chemistry Labs L-Carnitine was created.
Apr 27, 2022 Product News
GNC Acetyl-L-Carnitine Alpha Lipoic Acid has new variations: L-Carnitine
Apr 14, 2022 YouTube Video
ALPHA LION FORMULATOR DREW PETERS | PRICEPLOW PODCAST
Apr 14, 2022 Blog Post
Alpha Lion 2022 Update with Drew Peters | PPP #065
Drew Peters is now the Alpha Lion formulator, so we cover some of their supplements launched in early 2022 like SuperHuman Sport and SuperHuman Scorch
Feb 03, 2022 Product News
Gaspari Nutrition Liquid Carnitine 3000 was created.
Dec 12, 2021 Product News
Doctor's Best Acetyl-L-Carnitine was created.
Category: Acetyl L-Carnitine
Oct 06, 2021 Product News
Nutrex Lipo-6 Carnitine has new variations: L-Carnitine
Aug 31, 2021 Product News
AllMax Nutrition Liquid L-Carnitine 1500 was created.
Aug 19, 2021 Blog Post
5% Nutriton’s ALL DAY YOU MAY: Rich Piana’s LEGENDARY Amino Supplement
Rich Piana's ALL DAY YOU MAY is a post workout supplement that provides joint support and has a few different ingredients. But is it different ENOUGH?
Jun 24, 2021 Product News
VMI Sports L-Carnitine 1500 Heat Powder was created.
Jun 19, 2021 Product News
Alpha Lion SuperHuman Scorch was created.
Categories: L-Carnitine, Stimulant-Free Fat Burners
May 20, 2021 Product News
AP Regimen L-Carnitine 3000 was created.
Mar 08, 2021 YouTube Video
Best Carnitine Liquid?! SteelFit Steel Burn Frozen Rocket Pop!
Feb 15, 2021 Blog Post
SteelFit Blasts Off Steel Burn Frozen Rocket Pop for Presidents Day
SteelFit has announced a Frozen Rocket Pop flavor of STEEL BURN, their stimulant-free Carnipure-based liquid L-carnitine supplement to improve health!
Dec 16, 2020 Product News
Insane Labz L-Carnitine was created.
Dec 08, 2020 Product News
Betancourt L-Carnitine Plus 3000mg was created.
Dec 08, 2020 Product News
Jacked Factory Acetyl L-Carnitine was created.
Category: Acetyl L-Carnitine
Nov 27, 2020 Product News
Predator Nutrition L-Carnitine was created.
Nov 21, 2020 Product News
Repp Sports Thermo 2000 was created.
Sep 01, 2020 YouTube Video
ENERGY DRINK GAME CHANGER | Ghost Energy Tropical Mango Review
Jun 26, 2020 YouTube Video
Pure CarniPure L-Carnitine You Can FINISH: SteelFit Steel Burn
Jun 11, 2020 Blog Post
SteelFit Steel Burn: Unlock Fat Stores with L-Carnitine
SteelFit is known for their comprehensive line of weight loss products and one that really stands out is Steel Burn! Burn more fat with Carnipure!
Jul 27, 2019 YouTube Video
Fight Fat and Combat Carbs! | Ghost Burn INGREDIENTS Reviewed
Mar 09, 2019 YouTube Video
What is GBB (Gamma Butyrobetaine)? SYNMR's ProGBB Explained!
Feb 17, 2019 Blog Post
Muscle Building Supplements: The Next Generation (2019)
Muscle Building Supplements: The 2016 Guide. We all know about creatine, protein, and amino acids... but what are the NEXT generation muscle builders?
Feb 01, 2019 YouTube Video
VMI Sports | L-Carnitine 1500 HEAT Flavors Review
Nov 30, 2018 YouTube Video
BEST Nootropic Energy Drink | SNS Focus XT Review
Aug 27, 2018 YouTube Video
Performax Labs EAmino Max Review: Goodbye BCAAs!
Aug 23, 2018 YouTube Video
VMI Sports L-Carnitine 1500 HEAT Review: Feel the Heat!
Aug 21, 2018 Blog Post
L-Carnitine is Underrated. New Meta Review Reminds Us Why.
A new L-Carnitine review citing over 100 sources reminds us how incredibly good and safe this ingredient is... and we think L-Carnitine is underrated!
Jul 16, 2018 YouTube Video
Keto Connect Podcast: Supplements for Keto Dieters w/ Mike at PricePlow
Jul 12, 2018 Blog Post
GBB (Gamma-Butyrobetaine Ethyl Ester): Super Carnitine That Makes You Sweat?!
Dec 14, 2017 Blog Post
Jacked Factory Growth Surge: Essential Muscle Gains
Jacked Factory is back on the scene with their straightforward, no-nonsense daily muscle building and recovery supplement Growth Surge.
Oct 15, 2017 Blog Post
Keto Connect Podcast with Mike: Supplements for Keto | Episode #004
Need guidance about supplements for keto dieters? Check out Mike's 2017 Keto Connect podcast interview on "Keto for Normies" with Matt & Megha!
Jun 27, 2017 YouTube Video
Giant Sports Giant Keto Review - BHB Supplements WORK!
May 10, 2017 YouTube Video
NutraKey's Supplement Flavors Rule! Lex Kovacs Explains Why
Dec 27, 2016 Blog Post
Hi-Tech CarniSlim – Weight Loss Carnitine for Everyone!
Hi-Tech released a new stimulant free fat burner called CarniSlim that touts FIVE different forms of CarniSlim for weight loss!
Nov 29, 2016 Blog Post
MTS Insurgent – The Machine’s MAN MAKER
MTS Nutrition's back with Insurgent, an all-new supplement that’s specifically engineered to be an “extremely potent libido and testosterone booster.”
Oct 31, 2016 Blog Post
NutraKey Supplements: Committed to Making a Better YOU
NutraKey is a supplement brand that's known for their commitment to promoting healthful supplements and their focus on making the best you!
Sep 06, 2016 Blog Post
Northbound Nutrition BLEND – Cognitive Energy & Endurance
Blend from Northbound Nutrition is a clinically dosed cognition enhancing supplement perfect for work or working out. Maybe even a gaming supplement!
Mar 02, 2016 Blog Post
Magnum Carne Diem – Seize the Fat Loss!
Carne Diem is the newest non stimulant fat burner from Magnum Nutraceuticals that puts a truly unique spin on carnitine supplements.
Dec 09, 2015 Blog Post
iForce Finish Line: Anytime, Anywhere Gains “Post Workout”
iForce Nutrition Finish Line is the recently unveiled post workout that contains everything you want to speed recovery and full gains all day long.
Jan 29, 2015 Blog Post
PES ERGONINE – The Once-Per-Day Muscle Supplement
Athletix Ergonine has been touted as a once-daily muscle builder that covers all of your bases for less than a dollar per day. Does it add up? (YES!)
Oct 13, 2014 Blog Post
BSN’s DNA Series Is Finally Here!
BSN has made the announcement that their DNA Series will be launching soon! Check out this article for the most up to date information.
Apr 12, 2014 Blog Post
Cellucor C4 Ripped – The Fat Burning Pre Workout?!
Cellucor C4 Ripped is the new C4 variation that includes more fat burning ingredients and no creatine for a killer cardio or weight loss workout!
Sign up for future L-Carnitine news!
Click the button below to sign up for future L-Carnitine news, deals, coupons, and reviews!
L-Carnitine Reviews & Videos
Aug 27, 2018Performax Labs EAmino Max Review: Goodbye BCAAs!
Subscribe for more L-Carnitine news and alerts!