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Many fitness enthusiasts and athletes include L-carnitine as part of their supplement plan to help them improve performance and promote a healthy physique.

L-carnitine is an important type of amino acid that supports energy by bringing fatty acids to the mitochondria — the powerhouse cells of the body — to be used for fuel.

What Is L-Carnitine?

L-carnitine is one of two forms that carnitine comes in, the other being D-carnitine. L-carnitine is the active form of carnitine that is involved in the production and metabolism of energy. Though it's naturally-occurring in the body, it can also be found in certain foods or taken as a supplement.

Many people use L-carnitine to supplement their health and fitness routine as a means to maintain or lose weight, boost muscle building and even improve brain function.

Benefits of L-Carnitine

There are a number of a health and wellness benefits of taking L-carnitine, which is why many physically active individuals include it part of their regimen:

Boosts Endurance

Since L-carnitine is instrumental in the production of energy, many active individuals take it to increase endurance.

One particular study1 found that professional soccer players who took L-carnitine before training were able to exercise for longer time frames before reaching exhaustion. Another study2 showed that rats who were fed L-carnitine showed improvement in exercise endurance.

Helps With Weight Loss

L-carnitine may have a role in the weight loss industry because of its possible ability to help shed excess body fat. In fact, one study3 discovered that participants who took L-carnitine experienced a much greater amount of weight loss compared to a control group.

Helps With Muscle Recovery

Athletes may be able to recover from training faster by supplementing with L-carnitine. One study4 found that athletes who took L-carnitine before undergoing an athletic test had lower levels of certain markers of muscle damage compared to the group who took a placebo.

Improves Brain Function

Many people take L-carnitine for its effect on the brain in addition to its impact on the body. More specifically, L-carnitine may be effective in boosting cognitive and brain function.

Studies have found that L-carnitine5 supplementation may improve cognitive function and memory in the elderly and even reverse cognitive decline.

Normalizes Blood Sugar Levels

It has been suggested that L-carnitine may be effective at regulating blood sugar levels and protecting against insulin resistance. Studies6 have shown that diabetic patients who took L-carnitine showed an improvement in insulin sensitivity and regulation of blood sugar levels.

How to Use L-Carnitine

L-carnitine usually comes in capsule format, making it rather easy to take. Each capsule is dosed precisely, so the exact brand you take may come with different doses per capsule.

Recommended Daily Dosage

The recommended daily dosage of L-carnitine is 500mg to 2,000mg. That said, the exact dosage will depend on the type of L-carnitine supplement being taken.

For instance, doses as high as 2,500mg of acetyl-L-carnitine may be taken every day, while L-carnitine can be taken on doses as high as 4,000mg.

As with any supplement, it's advised to start with the lower end of the recommended daily dosage and gradually work your way up to minimize side effects.

Symptoms of L-Carnitine Deficiency

Inadequate intake of L-carnitine can be caused by a number of things, including not eating enough protein-rich foods, excess fluid loss as a result of diarrhea or vomiting, liver problems or taking certain pharmaceutical medication.

Signs of L-carnitine deficiency may include:

  • Decreased muscle tone
  • Muscle weakness
  • Brain fog
  • Fatigue
  • Irritability
  • Delayed motor development
  • Possible hypoglycemia if the liver is impacted

Foods That Contain L-Carnitine

As already mentioned, L-carnitine can be produced in the body, but it should also be obtained from outside sources to avoid deficiency and the side effects that come with inadequate levels in the body.

When it comes to L-carnitine food sources, animal products tend to be the best7. The following are food sources that have the highest level of L-carnitine:

  • Beef
  • Chicken breast
  • Codfish
  • Whole milk
  • Cheddar cheese
  • Avocado
  • Fish

Supplementing With L-Carnitine

L-carnitine is typically safe to take and does not usually present any side effects when used properly. However, some users may experience mild side effects from taking this supplement — especially when taken in high doses — including stomach discomfort, nausea, vomiting and diarrhea.

Certain individuals may not be suitable for L-carnitine, including:

  • Epileptic patients: L-carnitine could increase the risk of seizures in patients suffering epilepsy.
  • Those with hypothyroidism: L-carnitine could exacerbate the symptoms of hypothyroidism.

Is L-Carnitine Healthy?

L-carnitine is an important amino acid that's produced in the body but can also be obtained from foods and supplements in order to avoid deficiency. Many people take L-carnitine to boost their physical activity efforts, lose weight, and boost brain function.

Like other supplements, L-carnitine works best when in conjunction with a healthy diet and exercise routine, and should only be taken upon the advice and guidance of a physician.

L-Carnitine Supplementation With L-Carnitine: Energy Support

There are always certain instances where diet is not going to give you everything you need. There's no need to worry if your diet does not provide the necessary amount of L-carnitine. Oral supplements are available for those who want to make sure they are consuming enough in their daily diet.

L-Carnitine: Energy Support is a powerful, all-natural supplement that contains a clinically-proven dosage of L-carnitine. Learn more about L-Carnitine: Energy Support and UMZU's line of natural supplements by visiting our online showroom.

With crazy, busy schedules it is easy to be tempted by fast food, processed food, and an abundance of poor eating choices. With obesity and bad eating habits on the rise, it's more important now than ever to pay attention to what you put in your body. Your health is one of the most important investments you can make. After all, you will need it for years to come! Take care to make sure you are receiving adequate amounts of both macronutrients and micronutrients, as well as engaging in healthy exercise. Begin your journey to a healthier you today!

Citations and Sources

Orer G, Guzel N. The effects of acute L-carnitine supplementation on endurance performance of athletes. J Strength Cond Res. 2014;28(2):514-519. https://www.ncbi.nlm.nih.gov/pubmed/24263659.
Panjwani U, Thakur L, Anand J, et al. Effect of L-carnitine supplementation on endurance exercise in normobaric/normoxic and hypobaric/hypoxic conditions. Wilderness Environ Med. 2007;18(3):169-176. https://www.ncbi.nlm.nih.gov/pubmed/17914899.
Pooyandjoo M, Nouhi M, Shab-Bidar S, Djafarian K, Olyaeemanesh A. The effect of (L-)carnitine on weight loss in adults: a systematic review and meta-analysis of randomized controlled trials. Obes Rev. 2016;17(10):970-976. https://www.ncbi.nlm.nih.gov/pubmed/27335245.
Parandak K, Arazi H, Khoshkhahesh F, Nakhostin-Roohi B. The effect of two-week L-carnitine supplementation on exercise -induced oxidative stress and muscle damage. Asian J Sports Med. 2014;5(2):123-128. https://www.ncbi.nlm.nih.gov/pubmed/25834706.
Malaguarnera M, Cammalleri L, Gargante M, Vacante M, Colonna V, Motta M. L-Carnitine treatment reduces severity of physical and mental fatigue and increases cognitive functions in centenarians: a randomized and controlled clinical trial. Am J Clin Nutr. 2007;86(6):1738-1744. https://www.ncbi.nlm.nih.gov/pubmed/18065594.
Mingrone G, Greco A, Capristo E, et al. L-carnitine improves glucose disposal in type 2 diabetic patients. J Am Coll Nutr. 1999;18(1):77-82. https://www.ncbi.nlm.nih.gov/pubmed/10067662.
Office of Dietary Supplements - Carnitine. https://ods.od.nih.gov/factsheets/Carnitine-HealthProfessional/#h3. Accessed May 2, 2019.
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