L-Carnitine is an incredibly popular and well-researched supplement ingredient.
It’s often called an amino acid, but chemically, this isn’t exactly true. It’s more like if a B vitamin and an amino acid had an offspring. And that offspring helped you burn fat and recover faster.
Like B vitamins, It plays an important role in energy production. Specifically though, l-carnitine shuttle fatty acids into the mitochondria of the cell, where the fat can get burned as fuel.
This leads to increased energy and more fat burning.
The fat-burning link makes sense both mechanistically and anecdotally among thousands of users, but right now the evidence is lacking that there’s a direct link.
However, l-carnitine has many other benefits.
Many studies show that l-carnitine reduces ammonia levels, which is a marker of liver function.
So l-carnitine can be an effective supplement if you have liver problems (very common among bodybuilders who take certain performance-enhancing drugs).
For liver function, TUDCA is another popular supplement, and you can see our list of the best TUDCA supplements.
This meta-analysis looked at a bunch of studies and found that 2 grams per day of l-carnitine (a modest, normal dose) helped infertile men.
While the fat loss research on otherwise healthy, very active people is shaky, for those with metabolic syndromes (diabetes, obesity, high blood pressure), l-carnitine does seem to promote fat loss.
This benefit was found when researchers studied a specific, patented form of l-carnitine, CarniPure®. So if you want to use l-carnitine to reduce soreness and enhance recovery, look for products that contain CarniPure® l-carnitine.
Don’t worry, we will highlight this on our list.
Increases in cognitive function from l-carnitine specifically come from a form of l-carnitine called acetyl l-carnitine.
For example, this meta-analysis discusses acetyl l-carnitine’s potential for fighting dementia and other forms of cognitive decline.
This is because acetyl l-carnitine can cross through the blood-brain barrier, as has been examined in several studies like this one.
However, acetyl-l-carnitine hasn’t demonstrated many of the other benefits, like fat loss potential or increased recovery compared to l-carnitine l-tartrate.
With all of this said, here are the best l-carnitine supplements on the market.
There are tons of comprehensive products that include l-carnitine in them. Those didn’t make our list. Because l-carnitine often comes as capsules, it’s simple to take a pure product, and then add it to your supplement stacks based on your specific goals.
Especially because making a decision about l-carnitine supplementation is already complicated enough as it is. You have three different forms:
These all have differences, depending on your goals. We cover the research on these differences after the products.
And, they’re available in powders, capsules, and liquids. Let’s be honest with ourselves, capsules are almost always easier. Sometimes you pay for the convenience, though, so that’s also reflected in our ranking.
I don’t typically rank products higher just because they’re vegan, but anything with amino acids is an exception.
That’s because many non-vegan amino acid products are sourced from what’s called “animal by-product.” This is code-word for the absolute scraps and lowest-quality parts of animals, like rotting bones, bird feathers, and more.
I have still included some non-vegan products, but keep in mind what “vegan” means in this case. Vegan means it’s derived from plant sources, which are generally of higher quality.
Best Overall: Kaged L-Carnitine
Best For Fat Loss And Performance: Kaged L-Carnitine
Best Value/Bulk: Pure Bulk
Best For Cognition: MRM Acetyl-L-Carnitine
Kaged is known for only using premium, quality-sourced products, even if it means sacrificing profit margins. Their l-carnitine is no exception.
First, their product uses a patented form of l-carnitine l-tartrate called CarniPure®, which has been shown in many studies to improve recovery and reduce soreness.
Carnipure® is only manufactured by a unique production process by the Swiss life sciences company Lonza. Because of the patented production, they’re able to make the purest form of l-carnitine l-tartrate with the fewest impurities.
Basically, you get the most for what you pay for, without any impurities or unwanted ingredients.
Kaged’s l-carnitine comes in capsules that are easy to make a part of your pre-workout stack.
They’re also NSF-approved for sport, and vegan.
Every bottle comes with 250 capsules with 500mg of l-carnitine.
If you’re looking for the best cost-per-gram deal on the market from a third-party trusted brand, then PureBulk has what you’re looking for.
They even have bulk purchases of l-carnitine, l-carnitine l-tartrate, and acetyl-l-carnitine.
With a 100-gram bag for $16, you can’t beat the deal.
However, it does come as an unflavored powder, and it’s a bit bitter.
I’m a wuss, so what I do in these types of situations is mix them into smoothies or other pre-workout drinks, and that works fine.
As we mentioned, acetyl-l-carnitine is the only form of l-carnitine that has been shown to make it through the blood-brain barrier.
Therefore, it has unique benefits for cognitive health and slowing cognitive decline.
However, it hasn’t shown the other benefits that l-carnitine l-tartrate or other forms have.
This product from Double Wood is a simple, high-quality, great value ALC product.
It contains acetyl-carnitine and nothing else.
And it’s vegan.
You can get 60 capsules with 500mg of ACL for just 9 bucks.
This product from Double Wood is a simple, high-quality, great value ALC product. It’s a better value than MRM.
It contains acetyl-carnitine and nothing else.
Double Wood is known for their purity, and they display the lab results of every batch of their products.
Each bottle contains 150 capsules with 500mg of acetyl-l-carnitine. However, their product is not vegan.
This product is a bit more expensive for the serving. While it has 855mg, only 500mg of this is actually l-carnitine because it’s a form called l-carnitine fumarate.
That said, l-carnitine fumarate also has some differences between other forms.
L-carnitine fumarate is specifically used for heart and cardiovascular health, and it has been studied at length with various degrees of success.
This product is also vegan, and uses a patented form of l-carnitine fumarate, and is manufactured in an FDA-approved facility, so it’s also of the highest quality.
This liquid product comes in free-form l-carnitine. The taste, like all other liquid l-carnitines, is not bad, but it is kind of like “taking your medicine.” There are three different flavors. Trust me, they’re all average at best. But this isn’t a protein powder, there isn’t much room to play with taste.
Onto the more important stuff. Every bottle has 48g of l-carnitine total. If you average this out per cost, it’s more expensive than most of our other options.
But, if you prefer the liquid option, then this is one of the simplest and highest quality.
Jarrow’s product is also free-from. Every capsule contains 500mg of l-carnitine. It’s also a vegan product, which I’m a big fan of for this class of products, where the sourcing of amino acids can get questionable and of lower quality.
As usual, Jarrow has a solid product, and this is a vegan option as well.
Acetyl-l-carnitine has in a few instances worsened the symptoms of bipolar disorder. It has also interfered with thyroid hormone function at high doses.
The more common side effect is stomach discomfort and nausea. It seems to be tolerated better if you have something in your stomach already.
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