Best L-Carnitine Supplement
What is L-Carnitine?
L-Carnitine is an amino acid that helps with energy production. Amino acids are common to see in supplements, as they are essentially the building blocks of protein, but the names can sometimes be a little confusing.
In this case, L-Carnitine is similar to a lot of other compounds, such as acetyl-L-carnitine and propionyl-L-carnitine. If you see the name listed simply as “Carnitine”, this usually refers to all of the above-mentioned compounds.
L-carnitine is already naturally produced in our bodies, and can be found in many types of food as well, with red meat containing the highest concentrations.
Some people have lower levels of L-carnitine due to genetic disorders, other medical conditions, or the effects of particular prescription drugs. Usually, you won’t really perceive an actual effect of low l-carnitine levels until they become really low, but long term effects of low l-carnitine levels are thought, by some, to promote side effects of aging over time.
L-carnitine wasn’t originally introduced as a supplement for athletic performance. Originally, it was identified (or lack thereof) in those with genetic disorders, and as such, methods were developed to isolate and package l-carnitine and its related compounds in a form that could be taken orally or intravenously.
Many of the earliest observations surrounded cardiac muscle health and skeletal muscle health, among many others, but given these initial observations, it’s not entirely surprising that l-carnitine was eventually identified as a supplement that could hold some value to training athletes.
How Does L-Carnitine Work?
In the most general sense, L-carnitine helps use fat towards energy production, and also helps clean up some of the waste left behind from producing that energy. L-carnitine doesn’t necessarily hunt down more fat to use, but instead, makes the already on-going process more efficient.
Let’s go a little deeper into how L-cartinine is used in the body.
L-carnitine is mainly produced by the liver and kidneys, but at the end of the day, it mainly affects organs like the brain and heart, and also acts on skeletal muscle.
Our bodies use various types of cycles to create energy from various compounds. One of these cycles, called the citric acid cycle, is more highly dependent on L-carnitine. In this case, L-carnitine is responsible for transporting fatty acids into the mitochondria of cells. Mitochondria are responsible for energy production within a cell, and in this case, the mitochondria will receive the fatty acids it needs to eventually create ATP (energy) thanks to the transporting action of L-carnitine.
If L-carnitine is absent or in low supply, this could lead to a host of health problems.
L-carnitine’s job isn’t done there. Once it has delivered the fatty acid fuel to the mitochondria, L-carnitine will remain in the system in order to help transport toxic by-products out of the mitochondria.
Therefore, L-carnitine as a supplement doesn’t act to directly burn fat or add lean mass, but instead, helps optimize the citric acid energy cycle so that the cells in our body have an adequate supply constantly available energy, and that the cells are always able to eliminate toxic by-products before the accumulate too much and cause any damage.
Does Supplementing with L-Carnitine Help with Fitness Training?
Like many other supplements, especially those that are just beginning to be recognized as holding potential benefits, the degree to which L-carnitine can assist athletes is still relatively unclear.
To cut to the chase, it definitely appears that L-carnitine holds potential for those athletes looking to gain an extra edge, but the extent to which individual athletes benefit from supplementation varies. Some studies have shown great responses to L-carnitine supplementation, while others show slightly less responses. Here is a rundown of what supplementing with L-carnitine can do for an athlete:
Can L-Carnitine Help You Lose Weight?
You will often see L-carnitine marketed as a fat-burner. While there definitely is potential for L-carnitine to assist with the weight loss process, it’s not fully clear whether or not this is a direct benefit.
Given that L-carnitine plays a vital role in transporting fatty acids to the mitochondria for metabolism, it certainly makes sense. However, many health professionals are skeptical that supplementing with L-carnitine will utilize more fat for the burning process. Instead, many think that the improved metabolism and energy efficiency is the primary benefit, and as a result of increasing energy and possibly endurance, and athlete is more likely to get more out of their workout.
So why does this matter?
Basically, you can’t just take L-carnitine, sit around on the couch, and think you’ll get ripped. You still have to put in the work, but L-carnitine can help you with that.
Does L-Carnitine Increase Endurance?
You may have also heard that L-carnitine supplements can help increase endurance and overall athletic performance. In opinion, we would focus on endurance, since it’s an outcome that you can actually track.
To date, studies have been rather conflicting on this issue, but the more recent studies are now beginning to show stronger benefits to the athlete, mainly because they’re starting to figure out how to optimize intake.
For example, the first studies investigating the potential of L-carnitine to burn fat and improve endurance were performed in mice. This is always an appropriate starting point, but crucial parts of the study can be lost in translation, especially those who don’t actively work in science.
Dose is a major detail that is often left out, and in the early stages the dose can often be way lower or higher than the optimal dose, or even something that would be practical for humans. Many of these types of issues are part of the reason there is conflicting evidence.
Recently, more studies have begun using humans, particularly elite athletes, to see if L-carnitine holds any benefit for performance.
At first, results were a little lack-luster. Some showed solid improvements in performance and quality of life, while others showed some, albeit minimal benefits. One thing that is starting to be realized is that if you take L-carnitine with some form of carbohydrate, the subsequent release of insulin (due to ingesting carbs) helps direct the L-carnitine to the muscles, which seems to make it much more effective.
In one particular study, triathletes who took L-carnitine in combination with their regular training schedule showed better improvements in cardiovascular fitness than their triathlete counterparts who took a placebo.
Ok, back up a second. Carbs? It’s not often you hear that you should be taking a performance supplement with carbs.
Some athletes who are required to follow particular diets may not be so inclined to stack with carbs, but no need to worry; an alternate option has been recently recognized.
Instead of stacking with carbs, if you stack with omega-3s, this seems to yield similar improved benefits. This is more so seen with weight loss as opposed to increased muscular endurance, but overall, it appears this could be more useful overall than stacking with nothing.
Does L-Carnitine Help With Recovery?
As we mentioned previously, in addition to transporting fatty acids to the mitochondria for energy production, L-carnitine also helps eliminate waste products, keeping the process running smoothly and efficiently. Getting into the specifics can be a little confusing at times, as it involves somewhat complicated process that incorporate androgen receptors, testosterone, lactic acid, and protein synthesis, all at once.
The simplest way to put it is that L-carnitine allows you to get a head start on your recovery. As you’re working out, L-carnitine will help eliminate lactic acid from the muscles, allowing you to clear it faster after the fact.
Similarly, more androgen receptors and uptake of circulating testosterone can further assist in repairing muscles. The result? You can recover faster since you’re muscles have already starting healing to a greater extent than they normally would, and you have more efficient healing post-workout as well.
Is L-Carnitine Good for the Mind?
Often overlooked by athletes, a very similar compound to L-carnitine called acetyl-L-carnitine (one of the three that generally makes up “carnitine”), has showed benefits to increasing cognitive performance, as well as enhancing mood and motivation.
Acetyl-L-carnitine is considered an anti-oxidant that can help reduce the accumulation of heavy metals and some other toxins. Given it can cross the blood-brain barrier (not all compounds can do this), it can act directly on the brain to keep things clean and functioning smoothly.
Specific to mood and motivation, it is often recommended to take acetyl-L-carnitine along with Alpha Lipoic Acid and DHA. However, we do not recommend looking more into this if you’re not experiencing any major depressive episodes, and instead, just consider it a potential bonus benefit that you may experience when supplementing for physical performance purposes.
What Dose of L-Carnitine Should You Take?
As we previously mentioned, in addition to being produced naturally in our bodies, L-carnitine can be found in many different types of food. The highest concentrations are found in red meat, for example, lamb, beef, and pork. Lamb usually has the most (around 150-200mg per 100g), beef the second-most (75-100mg per 100g), and pork the third-most (20-40mg per 100g). After that, any other food item that has L-carnitine usually has really low amounts. For example, chicken has about 3-6mg of L-carnitine per 100g.
So while it is true that you can obtain everything you need via food, it can be difficult and expensive to stick to a strict dietary plan, especially when it revolves around one specific compound. Furthermore, vegetarians will have a really tough time trying to boost their L-carnitine intake through their diet, and on the whole, not all of the foods that contain L-carnitine are deemed “generally healthy”.
Therefore, given that you can find L-carnitine naturally in various food sources, we would recommend starting out with a relatively small dose, as you will be truly supplementing an already-existing intake of L-carnitine.
Many popular L-carnitine supplements come in capsule form with each capsule containing anywhere from 250mg to 1000mg. In our opinion, we would recommend 500mg per day to start, or maybe slightly more if you’re a vegetarian. We would not recommend exceeding 1000mg per day because any additional benefit is unlikely, particularly in the sense of fitness (as opposed to addressing a medical condition).
One important thing to keep in mind is that L-carnitine may take a while to have any noticeable effects. Some researchers have noticed a trend of increased benefits after the athlete supplements for a while. This is likely because higher amounts of L-carnitine need to be constantly present in the body to notice a difference. In this way, you want to mimic a natural environment. By taking L-carnitine for weeks to months, the body will begin to recognize these elevated levels as a natural state and more L-carnitine will be readily available for any time that you work out.
What are the Side-Effects of L-Carnitine?
Like most things, L-carnitine will be accompanied by some side effects. These can be extremely minimal provided you stick to the recommended dose. The most common side effects are stomach pain, diarrhea, nausea, and vomiting, and this can be expected with many of the things you start ingesting for the first time.
These side effects often go away once you become accustomed to the supplement. Just as common, but slightly more rare, are side effects like dizziness, loss of appetite, tingling, and swelling in the extremities.
Less common, but more severe, side effects include high blood pressure, increased heart rate, fever, or seizures. If these occur, it’s recommended you seek out a physician to discuss the issue in case there’s something else going on. In general, those aren’t the types of things you want to promote and monitor yourself, so better safe than sorry.
Reviews of the Top L-Carnitine Supplements
Cost Per Serving: $0.29 (1000mg)
NOW Foods is an extremely popular brand for almost every type of supplement. Their immense manufacturing capabilities allow them to reduce the cost during the process, and the result is a good value L-carnitine supplement.
Overall, it’s a little more expensive than other brands, but you get 100 capsules that are each 1000mg. The L-carninine is derived from the pure form of L-carnitine tartrate and has been clinically tested.
Other ingredients include stearic acid, magnesium stearate, silica, and vegetable coating. This is considered a vegetarian/vegan product, as it contains no sugar, salt, starch, yeast, gluten, corn, soy, milk, egg, shellfish, or preservatives.
The only thing we find a little inconvenient is that you’re stuck with the 1000mg capsules in this case. This can be a bit of a pain when first starting out with L-carnitine, as you may want to lower the dose for the first little bit to allow yourself to become accustomed, but that’s mainly our personal preference. Once you get rolling, it’s actually quite convenient because you only need to take one per day.
Price Per Serving: $0.3 (500mg)
This is another brand of L-carnitine supplement that has shown positive benefits for many of those who use it. One thing to be a little careful of is that Natureganics really promotes their products hard.
If you see claims or other types of marketing surrounding this product, just take it with a little grain of salt, especially when it comes to the results. While you likely will see some benefit if you follow the recommended dosage, it will take a while to see results (like any other L-carnitine supplement).
They often make it seem like a miracle supplement, but just understand that it may take a few weeks to notice the effects, and the degree to which you receive benefits can vary.
Otherwise, these are really well-liked supplements by tons of people, and there seem to be less reports of side-effects when compared with other brands of L-carnitine supplements.
It comes with 60 capsules each containing 500mg, and their recommended dosage is pretty standard – 2 capsules daily. We would suggest starting with one capsule for the first little while to become accustomed, and then increase to two per day. This may help prevent any unwanted side effects and will also stretch your supply a little longer.
Cost Per Serving: $0.24 (1000mg - 2 Capsules)
This is arguably one of the most popular brands for L-carnitine supplements. We would definitely recommend this brand as a starting point at the very least, but in our opinion, some of the main things they really promote about their L-carnitine doesn’t really make a huge difference for us.
For example, they mention using a “clinical strength dosage” in order to cut down on the amount of stuff in the capsules, ultimately providing a more pleasant experience than trying to swallow a massive capsule. However, when you really look at it, they say their 1000mg serving consists of 2 500mg capsules. So while we can’t argue with or against the purity of the L-carnitine, we wouldn’t be surprised if they simply split it up into smaller dose capsules and just tell you to take more.
Regardless, the BLI L-carnitine supplement is very well-liked and one of the more reputable brands out there. The 500mg capsules are actually perfect in our opinion, as you can ease into your supplement routine.
If you want to avoid side effects as much as possible, we would recommend starting out with one per day for the first little while, and then bump up to their recommended dosage of two per day.
Cost Per Serving: $0.14 (500mg)
Note the subtle, yet important, difference between this line of NOW Foods supplement and the NOW Foods L-Carnitine we reviewed above.
This line of supplements is acetyl-L-carnitine, which is more likely to improve cognitive performance than L-carnitine. This is the specific compound we referred to that can cross the blood-brain barrier to exert antioxidant effects and promote a healthy mind.
This line of acetyl-L-carnitine supplements come in 500mg capsules, which is on the middle end of the recommended dose.
They say to take 2 per day, and while this is ok, you may be more likely to notice initial side effects if you haven’t taken them before. These will likely be the common ones associated with stomach issues, but usually they go away pretty quickly.
The NOW Foods acetyl-L-carnitine contains three other ingredients: cellulose (which is used for the capsule), stearate, and stearic acid. These are all vegetable sources, and NOW Foods states that the product was not manufactured with wheat, gluten, soy, milk, yeast, egg, fish, shellfish, or tree nuts. BUT, they are produced in a facility that produces other products that contain those allergins, so if you’re severely allergic to any of those, it may be best to find something produced in a more isolated environment.