Best L-Carnitine Supplements


Our body primarily uses glucose to produce energy, but for optimum nutrition, we also intake fatty acids, amino acids, and other macro/micronutrients via our diet.

While glucose metabolism is the first step in our body to ensure adequate energy levels in us, in the case glucose levels are not high, fat metabolism becomes our go-to process to trigger natural energy production.

However, the latter process is not as easy to follow and requires complex series of biochemical reactions taking place. Perhaps one of the important amino acid derivatives used in the process is L-Carnitine, which is located on the mitochondrial membrane. With deficient L carnitine levels, our body cant burn fat.

Besides, scientific research also suggests that L carnitine plays an important role in weight loss, neurological and cardiovascular health, etc.

Let’s go into the details of L carnitine in this thread, and know more about what it is, the prospective benefits, the possible side effects, and whether you should start L carnitine supplementation.

Also, if you decide to start taking carnitine supplements, I will make sure to give out the 5 best L carnitine supplements available in the market that you can choose!

What Are The 5 Best L-Carnitine Supplements?

  1. L Carnitine powder by Bulk Supplements
  2. L carnitine tartrate by Thorne
  3. L carnitine capsules by Life Extension
  4. L carnitine by Nutricost
  5. L carnitine by Now Supplements
#1 Most Trusted L-Carnitine Supplement

L Carnitine powder by Bulk Supplements

L carnitine powder by Bulk supplements is perhaps a top product to vouch for!
This premium L carnitine is available in many packets, thus depending on your dosage requirements, you can buy the weight accordingly. But the top-selling one is a 1 kg (2.2 pounds) packet.

The powder has a mild or bland taste, therefore you can mix it with a glass of water, juice, or with other nootropic ingredients, such as GABA, CLA, and Coenzyme Q10 to optimize the benefits experienced.

With an overall rating of 4.5 out of 5 and so much of satisfied customers of Bulk supplements, you are getting nothing less than a miracle in such a competitive price range of $105.96.

Read Full Bulk Supplements Review


  • Most common powdered form available
  • Variety of options available to buy in terms of weight by packet
  • High customer rating


  • Other derivatives of L carnitine are not available
  • Other forms of intake are also not available i.e. capsules, tablets, liquid carnitine

#2 Most Trusted L-Carnitine Supplement

L carnitine tartrate by Thorne

L carnitine by Thorne is 2nd on my list of high-quality L carnitine supplements.

Thorne offers L carnitine tartrate which is an ideal dietary supplement for athletes and promises to enhance your heart health by improving your cardiovascular parameters, such as heart rate, cardiac output, total cholesterol levels, and also metabolism.

L carnitine capsules offered by Thorne comprises of 330mg per serving and contain 60 capsules in one jar which will cost you only $40.

With other set of ingredients, such as Hypromellose Capsule, Leucine, and Silicon Dioxide, L carnitine by Thorne should be your go-to option as your sports nutrition.

Read Full Thorne Review


  • Caters the athletic segment of the market
  • Capsules form is widely preferred
  • Enough servings available


  • Other derivatives not available to target the general market
  • Other forms of intake not available

#3 Most Trusted L-Carnitine Supplement

L carnitine capsules by Life Extension

Life extension offers 30 L carnitine capsules with each serving comprising 500 mg for just $12.03, making it an ideal option for vegetarians as the capsules are Non-GMO, gluten-free, and vegetarian as well. Other ingredients include vegetable cellulose (capsule), dicalcium phosphate, vegetable stearate, silica, etc.

Life extension advises you to take 1 capsule on an empty stomach, and not to exceed 4 capsules per day.
With 4.6 out of 5.0 global ratings, and some real-time customer experiences, I think L carnitine by Life extension is an economical choice.


  • Best option for vegetarians
  • Other derivatives are also available
  • Economical option


  • Other forms of intake not available
  • Contains less servings per jar

#4 Most Trusted L-Carnitine Supplement

L carnitine by Nutricost

L carnitine by Nutricost contains 100 servings with each serving constituting 1g. Perhaps it is important to note that Nutricost also offers other derivatives of L carnitine supplements, such as L carnitine tartrate, Acetyl L carnitine (ACLAR), etc.
This high-quality L carnitine powder is gluten-free, Non-GMO, and manufactured in FDA compliant facility.
This unflavored L carnitine by Nutricost will cost you as low as $13.95. With an overall rating of 4.5, and literally so many satisfied customers, follow the link and make your purchase now!


  • Derivatives of L carnitine available
  • Can last for long
  • Unflavored and no additives


  • Only powdered form of L carnitine available

#5 Most Trusted L-Carnitine Supplement

L carnitine by Now Supplements

The final vendor we are reviewing is from Now Supplements and they promise to offer the pure L carnitine which is also clinically tested.

The jar contains 100 tablets, and each serving comprises 10mg of L carnitine. With other ingredients such as Cellulose, Stearic Acid (vegetable source), Magnesium Stearate (vegetable source), Silica, and Vegetable Coating, L carnitine by Now Supplements is an ideal option for vegetarians/vegans.

Now supplements believe in high-quality research and clinical testing to optimize the customers’ experience, and they also suggest consuming L carnitine with additional products, such as Pantothenic acid and Lecithin.
The price range of the L carnitine by Now supplement is $24.83 and in my opinion, it’s the best option!


  • Best option for vegetarians/vegans
  • Clinically tested
  • Can be consumed with other supplements


  • Only powdered form available
  • Relatively expensive

What is L-Carnitine?

L carnitine or Levocarnitine, also chemically known as β-hydroxy-γ-N-trimethylaminobutyric acid is a naturally occurring amino acid derivative composed of Lysine and Methionine (1).

Structurally, it has 2 stereoisomers and is either found in D carnitine form or the L carnitine form. Perhaps only L carnitine is the naturally occurring useful enantiomer, and a major part of fat metabolism revolves around it.

Carnitine was originally extracted from meat in the early 1900s, and because of plenty of scientific research centered around it, many other derivatives of L carnitine are sold in the market in the form of carnitine supplements, such as acetyl L carnitine HCl (ACLAR), propionyl L carnitine, and L carnitine tartrate, etc.

Although kidneys can also synthesize some carnitine, it is essentially synthesized in the liver and is transported via blood circulation to the skeletal muscle and cardiac muscle where it is primarily stored (2).

How Does L-Carnitine Work?

Long-chain fatty acids need to undergo a Beta-oxidation pathway in order to yield energy (3). However, the beta-oxidation pathway occurs in the matrix of the mitochondria, and in order for long-chain fatty acids to be utilized, they need a shuttle that can help them cross the mitochondrial membrane.

This is where L carnitine and acetyl L carnitine come into play! It helps in the transport of long-chain fatty acids from the cytosol into the matrix of mitochondria so that stored body fat is burnt, and energy is made available (4). Besides, L carnitine is also used to transport toxic compounds made into the mitochondria out of the organelle.

On the other hand, D carnitine is a toxic form as it inhibits the absorption of other forms of L carnitine, and may cause carnitine deficiency (5).

Research suggests that Propionyl L carnitine causes the release of Nitric oxide while L carnitine L tartrate is used as a sports nutrition supplement because of its better absorption rate.

Perhaps amongst all the forms of L carnitine supplements, L carnitine and Acetyl L carnitine are mostly derivatives for optimum nutrition and energy levels.

Benefits of L-Carnitine

The primary goal of L carnitine is to support fat loss by stimulating mitochondria for burning fat and making sure that optimum energy is made available for the body to use.

Perhaps scientific research centered around L carnitine suggests numerous other benefits, thus making the consumption of L carnitine supplements an ideal choice.

Acetyl L carnitine form is seen to work as a neuroprotective agent and it optimizes brain function by delaying the onset of mental decline. Subjects administered L carnitine also experienced protection against Alzheimer’s and other brain disorders (6).

L carnitine is also found as an anti-diabetic medication as it maintains healthy blood sugar levels, and reduces the symptoms associated with type 2 diabetes mellitus. It is hypothesized that it does this by activating an enzyme called AMPK kinase (7).

L carnitine is also seen to influence cardiovascular health. A clinical trial involving L carnitine supplementation found out that the risk of developing hypertension dropped significantly. This can be correlated with the fact that propionyl L carnitine causes the release of Nitric Oxide (NO), which causes vasodilation of the blood vessels.

Patients with other chronic cardiovascular disorders, such as congestive heart failure and coronary artery diseases also experienced some level of improvements, however, this area needs to be researched more (8).

L carnitine also offers a wide array of benefits to athletes and fitness freaks. It enhances their exercise performance as it promotes muscle recovery as well as improves muscle soreness. Research suggests that L carnitine improves blood flow to the skeletal muscles ensuring muscle growth.

Thus, in order to enhance athletic performance, fitness pros, bodybuilders, and athletes often use it as a pre-workout supplement.

Furthermore, undecisive research suggests that L carnitine promotes weight loss. While this can theoretically be explained as L carnitine triggers stored body fat to be used to produce energy, not much scientific evidence exists to support the idea. Therefore, you shouldn’t use it as a weight-loss supplement.

Last but not least, evidence suggests that L carnitine supplements may improve male sexual health in two ways. It does this by synergistically working with Viagra (Sildenafil) and improving erectile dysfunction. Secondly, it may also increase sperm count and mobility.

Is L-Carnitine Legal?

Note that L carnitine supplement is not declared illegal by WADA or FDA if taken within approved limits. However, one shouldn’t infuse L carnitine above a certain threshold as it may interfere with regular athletic performance and give an unnecessary high-performance advantage.

Who Should Use L-Carnitine?

Perhaps L carnitine supplements can be used by anyone and everyone to produce energy in the body.

Patients searching for an effective brain health supplement can also use L carnitine. People diagnosed with any chronic cardiovascular diseases can also use L carnitine supplement to ensure heart health.

People diagnosed with metabolic syndrome can also dose up with L carnitine as it may reduce the severity of symptoms.

Also, if you are a vegetarian or on a strict vegan diet, you might have to start L carnitine supplements as you may be deficient in them.

Importantly, if you are a bodybuilder or an athlete, and you want to stimulate lean muscle growth and enhance athletic performance respectively, L carnitine can be your go-to supplement.

Forms of L-Carnitine

The good news is there are several different forms of L carnitine supplements available in the market. As discussed earlier, the potential benefits of L carnitine have led to more scientific research centered around it.

Thus, you will find many forms, such as L carnitine L tartrate, Acetyl L carnitine (ACLAR), Propionyl L carnitine, D carnitine, etc.

All of these can be consumed in many ways, such as in powder form, liquid form, and carnitine capsules, as well as tablets, are also available in the market. Because of the many versions available, one can use whatever form of L carnitine they feel comfortable with.

How to Use L-Carnitine

It is important to know the approved yet safe dosage guidelines for L carnitine supplements. Medical evidence suggests anywhere between 500mg to 2000mg of L carnitine intake per day.

However, some L carnitine derivatives, such as L carnitine tartrate can be consumed as high as 4 grams per day owing to their pharmacokinetics.

Because L carnitine is sold in many forms, it depends on your personal choice now. If you are a fan of liquid form, all you have to do is add the concentrated version of the L carnitine supplement into your glass of water.

If you opt for powder form, the guidelines remain the same. Add an equivalent scoop of the powdered L carnitine into any energy drink and whip up the benefits!

Lastly, L carnitine pills are also available in the market. You can either choose between L carnitine capsules or tablets.

Side Effects of L-Carnitine

Because L carnitine is naturally produced in your body from the two essential amino acids, it is not known to cause any significant adverse effects in your body if taken optimally.

You may experience nausea, dizziness, vomiting, upset stomach, diarrhea, and fishy body odor. There is some evidence that suggests that higher doses of L carnitine can also increase your blood levels of trimethylamine-N-oxide (TMAO) (9).

It is also important to note that L carnitine supplements may interact with your other ongoing medications. Perhaps you should definitely consider consulting your physician before starting on L carnitine supplementation.

Where To Buy L-Carnitine Supplements Online?

This is a very important yet confusing decision to make as there are many vendors in the market claiming to sell high-quality L carnitine supplements.

But, don’t worry!

After carefully considering the ingredients, ratings, reviews, and also pricing range, I have chosen the top 5 L carnitine supplement vendors.

Read the guide above to make the best decision for you!

Is L-Carnitine Effective for Fat Loss?

High-quality L carnitine can act as a stimulant-free fat burner because of its mechanism of action. Because it will act as a shuttle for body fat to cross the mitochondrial membrane, it can help you in burning fat.

This will alleviate your fat reserves in the body to a greater extent.

When Should I Take L-Carnitine?

While L carnitine deficiency is quite rare, starting on L carnitine supplements will solely depend on your own wish.

Considering the pharmacokinetics of the compound, L carnitine will best be absorbed in an empty stomach. Thus, the ideal time for L carnitine intake is either in the morning or it can also be used as a pre-workout supplement. Approximately one hour prior to your workout regime would yield optimum benefits.

Nonetheless, I would recommend splitting your dosage equally into 2 to 3 shifts.

How Much L-Carnitine Should I Take For Weight Loss?

By books, L carnitine should help you lose weight considering how it works at a cellular level. However, clinical trials involving subjects who were administered L carnitine didn’t experience any weight loss.

Due to the mixed scientific evidence, I would highly suggest not to consider L carnitine purely as a weight loss supplement.

You Might Also Like