What Is L-carnitine and Does it Help in Weight Loss?

    What Is L-carnitine and Does it Help in Weight Loss?

    The word “L-carnitine” may leave people feeling confused if not used in the proper context. If you follow sports, you might hear it mentioned every so often. L-carnitine is actually a popular supplement for athletes; so you might hear it in ads while watching basketball or other sports. That being said, many questions still remain about L-carnitine. Does it help in weight loss? What benefits it can actually provide even for non-athletes?

    What is L-carnitine?

    L-carnitine is a compound and amino acid derivative that occurs naturally in the human body. It is a co-factor of several enzymes. It is necessary for the transformation of free long chain fatty acids to acylcarnitines. Carnitine, by itself, helps make energy in your body. Most of it is derived from the heart, skeletal muscle, liver, and kidneys.

    L-carnitine is already naturally produced by the body. Thus, only people with some genetic problems and diseases (like pre-term babies) may have low levels. For these individuals, these supplements may help.

    L-carnitine has also been shown to help prevent cyclic vomiting syndrome as it helps the body overcome difficulty turning food into energy.

    While popular among athletes, no conclusive study has found that it helps improve sports performance, muscle adaptations, or endurance. This lack of consistent evidence has not prevented the trend of selling it as a supplement for athletes looking to improve their physical endurance and performances.

    Where can L-carnitine be found?

    Some food contains L-carnitine because it helps turn fat in your body into energy. This is also why it can be found in many supplements.

    Carnitine can be found in many animal products, with red meat having the highest levels. A 4-ounce beef steak has an estimated 56 mg to 162 mg of carnitine. Carnitine is also found in smaller amounts in chicken, milk and dairy products, fish, beans, and avocado.

    The carnitine content in most dairy products ranged, approximately, between animal tissues and plant-derived food with concentrations ranging from 8 to 530 mg.

    One study points out that 57–84% of L-carnitine is absorbed when it’s consumed from food, compared to only 14–18% when taken as a supplement.

    L-carnitine for weight loss

    Since L-carnitine has proven so effective in turning food and body fat into energy, it is natural to assume that it can help burn fat. That would then result in weight loss, something many people are always looking for.

    A series of randomized control trials in 2016 confirms this, concluding that adults receiving carnitine ended up losing weight. Meanwhile, other clinical trials in 2020 concluded that supplementation resulted in a modest reducing effect on body weight, body mass index, and fat mass, especially among obese adults.

    Still, the overall results of studies regarding L-carnitine and weight loss have been mixed. While it may aid in weight loss for older adults and those suffering from obesity, diet and exercise still need to be followed.

    Taking L-carnitine may make certain conditions worse like hypothyroidism and seizure disorders. It may also interact with prescription medications and may increase the risk of bleeding in patients taking blood thinners. Patients should check in with their doctor before taking any supplements especially if they have underlying health conditions.

    With its effectiveness in weight loss and as a popular supplement for athletes, L-carnitine may also help certain patients survive heart attacks, have less heart rhythm disturbances, and less chest pain.

    Further research is needed regarding use of this supplement for people suffering from peripheral artery disease.

    Key takeaways

    Naturally produced by the body, L-carnitine can also be found in several kinds of food, particularly red meat. It helps the body turn fat and food into energy. This has resulted in in supplements that athletes use on a regular basis.

    Studies have shown that adults receiving L-carnitine effectively lost body weight and fat mass. Consuming L-carnitine may actually help adults battling obesity as the compound helps in the body’s energy transfer.

    Learn more about diet and weight loss here.

    Hello Health Group does not provide medical advice, diagnosis or treatment.

    Medically reviewed by

    Stephanie Nera, RPh, PharmD


    Written by Jason Inocencio · Updated Jul 25, 2022