7 Best L-Carnitine Supplements in 2024

Interested in trying L-Carnitine? While this supplement is often branded as a fat burner, it’s much more useful for improving exercise performance and improving recovery.

Top 7 Best L-Carnitine Supplements Reviewed

1. BulkSupplement L-Carnitine – Top Pick
2. L-Carnitine by Nutricost
3. Recharge by Legion
4. L-Carnitine by NOW Foods
5. L-Carnitine by Source Naturals
6. Nutrabio Labs, L-Carnitine
7. GNC L-Carnitine

Product	Total	Servings Per Tub (for 2 g of carnitine)	Nutrition Label Transparency	Value for Money
Bulksupplements	29.5	10	9.5	10
Nutricost	29.5	10	9.5	10
Legion	29	9.5	9.5	10
NOW Foods	27	9	9.5	8.5
Source Naturals	26	8	9.5	8.5
Nutrabio Labs	26	8	9.5	8.5
GNC	25.5	8	9.5	8

Starting our list of the best L-Carnitine supplements, our top pick goes to Bulk Supplements. Easily offering the best value for your money on our list, this supplement offers a serving of L-Carnitine at a fraction of the price of some competitors.

First, this is one of only a couple of powder-based supplements on our list. Although some may prefer capsules, as you’ll see powder is significantly cheaper on average.

Keep in mind that most of the products on our list have a dose of 0.5-1g dose per serving. However, we recommend taking 2g throughout the day to maximize the effects of the supplement.

Because of this, we’ve standardized the serving sizes and price per serving to a 2g dose for all the products on our list. More information on how to take L-Carnitine can be found in our buyer’s guide below!

This is the product on our list with the largest amount of L-Carnitine per package. You’ll be getting 500 servings in each 1kg bag. While this is a lot, if you’re sure you’ll be taking L-Carnitine for a while then this is ideal.

It should also be noted that this product is Lab Tested and Third Party Tested. It’s also certified to be manufactured at cGMP standards. We’ll be touching on certifications like this throughout our list.

This is because L-Carnitine supplements and other “fat burners” are often produced with very low quality standards which makes quality certifications that much more important.

As mentioned, the main draw of this product is the price. Each 2g serving of the supplement will only cost you ~$0.08, easily making this the cheapest supplement on our list. For reference, some of the other products are up to 10 times more expensive than this one!

Next up on our list is another powder-based supplement that’s very similar to Bulk Supplements’ product.

As mentioned, this is the second and only powder-based pure L-Carnitine supplement on our list. Like Bulk Supplements, this product comes in a 1g serving size. Keep in mind you’d need to take two 1g servings a day to maximize effects!

You’ll be getting significantly fewer servings than you would with Bulk Supplements, with Nutricost only offering 125 per 250g package.

Also like Bulk Supplements, this product is GMP compliant and Third Party Tested. It also has a seal claiming it is “Nutricost Quality Guaranteed”. Certifications like this are important with any L-Carnitine supplement, so keep this in mind when shopping around!

Although this is a similar product to Bulk Supplements, it is more than twice as expensive! Each serving will cost you around ~$0.20.

Next on our list is the only supplement to contain more than just L-Carnitine. Instead, this is a full post-workout supplement with two other active ingredients. Let’s take a closer look!

The main active ingredient you’ll be getting in this supplement is 5g of creatine. Creatine is one of the most well-studied and effective sports supplements available. Its benefits include increased high-intensity exercise performance, improved recovery, and reduced fatigue.

A standard dose is 5g a day, making this serving size ideal. You’ll also be getting 2.1g of L-Carnitine in each serving, which is an ideal daily dose.

You can get this supplement in a solid 60 servings per container as well, which should be enough to last you about 2 months of daily use.

While there is no mention of gCMP certification on Legion’s website it does appear to be tested for purity by Labdoor.

This is also the first and only flavored supplement on our list. You can get Legion’s Recharge in a solid 7 different flavors.

Finally, this is also the most expensive product on our list at ~$1.00 per serving. This price is because of additional ingredients like Creatine. But, it’s worth noting you could buy Bulk Supplements L-Carnitine as well as a cheap creatine supplement and it would still be cheaper than Legion.

Next on our list is the first capsule-based supplement we’ll be looking at from NOW Foods. Let’s see how it stacks up with the powder-based supplement we covered above.

NOW comes in 500mg veggie capsule servings, with 60 servings per container. It’s worth noting that it says there’s 500mg of L-Carnitine from 746mg of L-Carnitine L-Tartrate. This means you’ll only need ~3 capsules to get ~2g of total L-Carnitine L-Tartrate.

Unlike Kaged, however, NOW proudly displays its GMP certification on its product page. Another pro is that NOW Foods is partnered with Vitamin Angels, a charity that brings healthcare to underserved communities.

There is a significant jump in price between Kaged and NOW’s product. These capsules will cost about ~$0.67 per serving per 2g serving of L-Carnitine L-Tartrate.

Closing off our list, the final capsule-based supplement we’ll be looking at comes from Source Naturals. While this is a similar basic product to the rest of the capsules on our list, it should be noted that it’s quite expensive. Let’s take a closer look.

Like GNC’s product, you’ll be getting 120 capsules at 500mg each. If you’re looking to take a standard 2g/day, this will last you about a month. Compared to the other capsules on our list, this is a fairly standard amount of servings per container and should last you about a month.

Also similar to GNC, Source Naturals makes no claims about testing or certifications whatsoever. This is somewhat disappointing considering the price per serving, which we’ll cover in a moment. This is also only 1 of 2 non-vegan products on our list as it contains gelatin in its capsules.

This is easily the most expensive capsule-based supplement on our list at ~$1.76 per serving, which is almost twice as much as Legion’s multi-ingredient supplement.

Especially considering downsides like low servings per container and a lack of certifications, it’s unclear why Source Naturals product has such a hefty price tag. Overall, while this will still get the job done, you can find very similar supplements for significantly cheaper!

Next up on our list is a product that’s very similar to NOW in nearly every way, although it does come up short in a few key areas. Let’s take a closer look at Nutrabio’s L-Carnitine.

Similar to NOW foods product, each capsule has 735mg of L-Carnitine L-Tartrate for 500mg of total L-Carnitine. This means you’ll only need to take 3 capsules for a ~2g dose. However, this package only contains 30 complete 2g servings at 3 capsules per serving. This means it will only last you about a month with daily use.

Also, NutraBio is HPLC Lab Tested for potency. Also, although they claim their product is “Free of Harmful Impurities”, there is no third-party certification to back this claim up.

Finally, this product comes at a similar price point to NOW. Each 2g serving will cost you around $0.67.

Closing off our list is GNC’s L-Carnitine, which is also very similar to the previous 3 products we’ve covered. Let’s take a closer look.

You’ll be getting the standard 500mg serving at 120 total capsules. This means you’ll be getting 30 days worth of L-Carnitine at 2g/day.

Like the previous product, there are no claims made about any third-party testing or certification. It’s also worth noting that this is the only supplement that isn’t vegan-friendly on our list as it contains gelatin in its capsules.

Finally, this is slightly cheaper than NOW and Nutrabio, although not by much. Each 2g serving will cost you ~$0.83. For reference, that’s nearly double Kaged’s price and 10 times Bulk Supplements price!

What Is L-Carnitine And How Can It Be Useful For An Athlete?

L-Carnitine is a non-essential amino acid derivative, it is naturally produced by the body. It can also be found in foods like beef, and pork, albeit in very small amounts. The average person synthesizes between 11-34mg of carnitine naturally per day.

Supplementation with L-Carnitine is common for many different reasons. These include treatments for peripheral artery disease, infertility, and metabolic syndrome. However, does it have any applications for athletes?

As we’ll be covering below, supplementation can be used to increase plasma carnitine levels, which may have several applications for athletes. These include improving exercise performance and recovery. It’s also worth noting these results may be especially prevalent in vegans and vegetarians.

✅ May Improve Exercise Performance 

First, let’s take a look at how L-Carnitine directly impacts performance. It’s thought that L-Carnitine may improve exercise performance based on its role in energy metabolism.

One study concluded that L-Carnitine L-Tartrate delivered an 11% increase in work output over 24 weeks. The participants were given 2g daily alongside 80g of carbohydrate.

It’s worth noting the difference between L-Tartrate and other forms of L-Carnitine like Glycine Proionyl. One study concluded that Glycine Propionyl L-Carnitine supplementation showed no significant effects on aerobic or anaerobic exercise.

This shows that other forms that aren’t L-Carnitine L-Tartrate won’t necessarily produce the same effects.

For L-Carnitine to benefit athletes, muscle carnitine levels need to be increased, and it appears this is only possible with supplementation of L-Carnitine L-Tartrate and not alternative forms of the supplement.

As we’ll examine below, many of the exercise benefits of L-Carnitine may be largely due to its benefits in regard to recovery. However, it does appear to have direct applications for performance via things like improved blood flow and increased androgen receptor density in muscle cells.

✅ May Help With Post-Exercise Recovery And DOMS 

L-Carnitine appears to greatly improve recovery by helping to reduce blood lactate levels and oxidative stress after resistance training.

One study examined the effects of L-Carnitine on recovery as well as exercise capacity. They found that 9 weeks of supplementation with L-Carnitine led to increases in lifting volume as well as reduction in blood lactate levels and antioxidant capacity post-exercise.

Interestingly enough, it does not appear that carbohydrates were administered alongside L-Carnitine in this study. While they were used in the other study covered above, this shows that carbohydrates are not necessary for L-Carnitine to be effective.

While it’s not explicitly stated by the study, L-Carnitine’s effects on increased exercise capacity are likely due to increased blood flow, delivery of oxygen to muscles during and after exercise as well as the supplements effects on recovery.

✅ May Be A Decent Supplement For Vegans

Finally, L-Carnitine may be of special interest to vegans and vegetarians. Because L-Carnitine is an amino acid, vegetarians will have lower plasma carnitine concentrations. It appears that L-Carnitine supplementation will lead to significantly higher increases in muscle carnitine levels of vegetarians when compared to omnivores.

It’s worth noting the study that found this did not report significant increases in exercise performance for either vegans or vegetarians. However, it does not appear carbohydrates were administered alongside the L-Carnitine in this study which may be why.

Regardless, this study shows that L-Carnitine supplementation will have a stronger impact on vegetarians.

Hot Topic: Is L-Carnitine A Fat Burner?

If you came to this article looking for the best L-Carnitine for weight loss, you probably noticed we haven’t mentioned anything about weight loss. So, is L-Carnitine an effective fat burner or not?

L-Carnitine is most frequently marketed as a fat burner/weight-loss supplement. However, we do not recommend taking L-Carnitine for fat loss, as research shows it is not especially beneficial in this regard.

The reason L-Carnitine is commonly seen as a fat burner is because it plays a crucial role in lipid oxidation in the body. However, it is clear that supplementation won’t directly help with weight loss without being in a caloric deficit.

Arguably the best supplement for fat loss is caffeine, as it will help increase energy expenditure without additional calorie intake. This will make it easier to eat less while exercising and maintain a consistent caloric deficit.

While L-Carnitine is a valid supplement for improving recovery and exercise performance, it does not appear to be an effective supplement for fat loss.

How To Choose The Best L-Carnitine Supplement?

As with any supplement, there are several factors you’ll want to consider before purchasing L-Carnitine. These include the type of L-Carnitine, what form it comes in, third-party certifications, and price per serving. By considering all these factors you can make a more informed choice.

1. Choose L-Carnitine Tartrate 

The 2 most common forms of L-Carnitine available are Acetyl-L-Carnitine and L-Carnitine Tartrate. All of the products on our list are formulated with Tartrate, and this is the form we recommend.

The reason for this is that the vast majority of studies on L-Carnitine for exercise performance use L-Carnitine Tartrate. Tartrate is simply better researched in terms of exercise.

2. Choose A Powder Or Capsule Form

Next, you’ll want to decide whether you’d prefer a powder or capsule-based supplement.

The obvious pro to powders is that they’re significantly cheaper. The 2 pure L-Carnitine powders on our list are a fraction of the price of the various capsules. However, powders may have more of an unpleasant smell and taste when compared to capsules.

Capsules will be easier to ingest, especially when taking multiple servings throughout the day. Just keep in mind you’ll be paying a premium for this convenience.

Note that we did not cover liquid L-Carnitine in this article. Aside from powder and capsules, L-Carnitine is commonly sold in a liquid form as well. The reason we didn’t include any liquid supplements is that similar to Acetyl-L-Carnitine they aren’t as well researched as the supplement in powder or capsule form.

While results will likely be similar, we recommend sticking with either capsules or powder for the time being.

3. Pay Attention To Third-Party Certification

L-Carnitine is typically considered a “fat burner”, and these supplements have an especially high-risk effect of containing unspecified or potentially dangerous ingredients.

This is why we’ve emphasized buying products that contain third-party quality certifications. GMP certifications are some of the most reliable signifiers of a high-quality product. 

4. Consider Price Per Serving

Because the best results from L-Carnitine have been shown from 2g doses, this is what we’ve decided upon as a standard dose. If you’re prioritizing price, then buying a simple powder supplement is the way to go. If you’re alright with spending more for convenience, then feel free to consider capsule-based supplements as well.

How To Use L-Carnitine Correctly? 

The following guidelines for taking L-Carnitine properly are based on the studies mentioned above. We recommend following several simple steps for optimal effectiveness.

Some of the studies that demonstrated the best results also administered L-Carnitine split into 2 servings throughout the day. This is also what’s recommended by many of the supplements on our list.

This is likely to help with more even absorption into the body throughout the day. However, it’s unclear if taking 1 larger dose will lead to less absorption overall. Really, whatever’s most convenient for you will work best.

To help with exercise performance, it’s common to take L-Carnitine before hitting the gym. However, to help with recovery it appears there’s more evidence to support taking the supplement after working out. Overall, timing shouldn’t make a major difference in the cumulative effects of the supplement.

Based on studies, it appears that 2g of L-Carnitine throughout the day will be sufficient to produce results related to recovery and improve overall exercise performance. Some studies used a higher dose of 4g throughout the day, so feel free to experiment with higher doses as well to maximize effectiveness.

While L-Carnitine is largely considered safe for human use, as we’ll mention later on, it may have unforeseen effects relating to cardiac health. As a result, we recommend consulting with a doctor before use if you’re concerned.

What Else Should You Know About L-Carnitine Before Buying It?

While L-Carnitine is generally considered safe, there are a few things you should consider before beginning L-Carnitine supplementation. These include the risk of potential gastrointestinal issues, an unpleasant odor, and an increased likelihood of cardiovascular events.

1. May Cause Gastrointestinal Symptoms

First, one of the most prevalent side effects of L-Carnitine supplementation is gastrointestinal distress. This includes nausea, vomiting, cramps, and diarrhea.

It’s worth noting that these side effects are most likely to occur when taking L-Carnitine on an empty stomach. With L-Carnitine being most effective alongside carbohydrates anyway, we recommend taking this supplement at mealtime to avoid any gastrointestinal side effects.

2. May Result In A 'Fishy' Body Odor

Next, it appears that L-Carnitine may result in an unpleasant “fishy” body odor when taken in high doses. This is coupled with the fact that the supplement often has an unpleasant smell to begin with.

It’s worth noting that body odor is only apparent with doses of more than 3g/day. If you’re planning on taking a high daily dose of L-Carnitine, splitting it up throughout the day may help reduce this side effect. With lower doses of ~2g/day, it appears this side effect is milder.

On top of body odor, L-Carnitine will likely also cause fishy breath after taking it, especially in powder form. Because of this, we recommend brushing your teeth or using mouthwash immediately after use to keep your breath fresh!

3. May Increase The Risk Of Cardiovascular Events

Finally, and most seriously, L-Carnitine may have dangerous implications for those with heart problems.

Namely, L-Carnitine appears to raise levels of Trimethylamine N-Oxide (TMAO) in the blood. Increased TMAO may increase the risk of atherosclerotic cardiovascular disease (ASCVD). This is a disease that clogs your arteries and can lead to further serious health consequences.

It’s worth noting that L-Carnitine is often used to treat symptoms of Peripheral Artery Disease as well. So, its overall effects on cardiac health are somewhat up for debate.

Because of this, those with cardiac issues should consult with their doctor before beginning L-Carnitine supplementation. This is especially true if they have a pre-existing heart condition.

FAQ

What Should Be Taken With L-Carnitine?

Some studies that demonstrated positive results administered 80g of carbs per 2g of L-Carnitine (different from LCLT). However, it does not appear this is necessary to get optimal effects from this supplement (LCLT 🙂), and it can just as well be taken on its own.

However, having food alongside L-Carnitine may be beneficial in preventing gastrointestinal symptoms.

Which Is Better: Fat Burner Or L-Carnitine? 

While L-Carnitine is frequently marketed as a fat burner, it does not appear to have significant effects on weight loss. Overall, most fat burner supplements will not have a significant effect on the body’s ability to lose weight.

However, L-Carnitine does have uses including improving exercise performance and recovery. Therefore, it will likely be more beneficial overall when compared to most fat burner supplements!

Who Should Not Take L-Carnitine? 

While L-Carnitine is generally considered safe for most people, it does appear there are some associated risks for those with pre-existing cardiac conditions. This is because L-Carnitine may increase the risk for artery-clogging ASCVD.

As a result, you should consult with your doctor before beginning L-Carnitine supplementation, especially if you have any pre-existing cardiac issues.

What’s The Best Form Of Carnitine?

The best form of carnitine for exercise performance is L-Carnitine Tartrate. This is because Carnitine Tartrate is what’s been most heavily researched in terms of exercise performance. We recommend sticking with Tartrate as its effect on exercise performance is better understood. 

Is L-Carnitine For Females Or Males?

While most of the studies covered in this article were done on males, there is little reason to suspect that L-Carnitine would have any different effects on women. While studies focusing primarily on women would be interesting, as of now we can assume effects will be similar for both sexes.

Conclusion

L-Carnitine is most commonly branded as a fat burner, although this isn’t what this supplement is best suited for. Instead, consider L-Carnitine supplementation for improved recovery as well as increased exercise performance.

An optimal dose of L-Carnitine appears to be 2g daily, administered over 2 servings. However, timing will not be especially important for the supplement’s cumulative effects.

Our top pick for a high-quality and budget-friendly L-Carnitine supplement is BULKSUPPLEMENTS.COM L-Carnitine. If you would prefer a capsule-based supplement, check out L-Carnitine by KAGED instead! We hope our L-Carnitine reviews were able to help you pick a supplement that’s right for you!

Have you ever taken L-Carnitine before? Were you aware that it’s more effective as a recovery booster rather than a fat burner? Let us know your thoughts in the comments below!

Also Read:

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• L Glutamine vs L Carnitine
• Best Glutamine Supplement

References:

1. "Facts About the Current Good Manufacturing Practices" FDA, https://www.fda.gov/drugs/pharmaceutical-quality-resources/facts-about-current-good-manufacturing-practices-cgmp 
2.  Richard B Kreider "International Society of Sports Nutrition position stand" NCBI, https://pubmed.ncbi.nlm.nih.gov/28615996/ (2017 Jun 13)
3. VitamineAngels, https://vitaminangels.org/
4. "L-Carnitine" Oregon State, https://lpi.oregonstate.edu/mic/dietary-factors/L-carnitine
5. "L-Carnitine" Examine, https://examine.com/supplements/carnitine/
6. Benjamin T Wall "Chronic oral ingestion of L-carnitine and carbohydrate increases muscle carnitine content and alters muscle fuel metabolism during exercise in humans" NCBI, https://pubmed.ncbi.nlm.nih.gov/21224234/ (2011 Feb 15)
7. Webb A Smith "Effect of glycine propionyl-L-carnitine on aerobic and anaerobic exercise performance" NCBI, https://pubmed.ncbi.nlm.nih.gov/18272931/ (2008 Feb)
8. William Kraemer "L-Carnitine Supplementation: A New Paradigm for its Role in Exercise" Academia, https://www.academia.edu/19090665/ (2005)
9. William J Kraemer "Androgenic responses to resistance exercise: effects of feeding and L-carnitine" NCBI, https://pubmed.ncbi.nlm.nih.gov/16826026/ (2006 Jul)
10. Majid S Koozehchian "Effects of nine weeks L-Carnitine supplementation on exercise performance, anaerobic power, and exercise-induced oxidative stress in resistance-trained males" NCBI, https://pubmed.ncbi.nlm.nih.gov/30661327/  (2018 Dec 31)
11. Katerina Novakova "Effect of L-carnitine supplementation on the body carnitine pool, skeletal muscle energy metabolism and physical performance in male vegetarians" NCBI, https://pubmed.ncbi.nlm.nih.gov/25612929/ (2016 Feb)
12. Kent Sahlin "Boosting fat burning with carnitine: an old friend comes out from the shadow" NCBI, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3099008/ (2011 Apr 1)
13. "Carnitine" AIS, https://www.ais.gov.au/__data/assets/pdf_file/0017/1048310/Carnitine-InfographicFINAL.pdf
14. Yujin Lee "Longitudinal Plasma Measures of Trimethylamine N-Oxide and Risk of Atherosclerotic Cardiovascular Disease Events in Community-Based Older Adults" NCBI, https://pubmed.ncbi.nlm.nih.gov/34398665/ (2021 Sep 7)