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A Guide to L-Carnitine on Keto

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  Published on June 21st, 2022
  Reading time: 4 minutes
  Last modified August 1st, 2023
L-carnitine supplement on keto

There’s always a buzz about one keto supplement or another and how it can boost fat burning and weight loss and increase your energy. It can get a little confusing, and you might be wondering which supplements you should take if any. What about L-carnitine on keto? What is L-carnitine, and what are the benefits? How does L-carnitine fit into a keto diet?

What Is L-Carnitine?

Discovered in 1905, L-carnitine is a water-soluble amino acid derivative your body naturally produces for energy. It’s also present in animal proteins like chicken, fish, and beef. Red meats like beef have higher amounts of L-carnitine, and it’s also found in smaller amounts in other foods like milk and dairy products, avocado, and beans.

Vegans obtain less carnitine from their diets, and for many people, it’s not a problem because their bodies naturally produce enough. Some vegans and vegetarians, though, can run into carnitine deficiencies over time.

Carnitine is involved in energy production because it transports fatty acids into the mitochondria of your cells, where they can be burned for energy. The mitochondria are like the powerhouses or engines of your cells that burn fats to create usable energy [1] [2] [3].

Your body produces L-carnitine from the amino acids methionine and lysine, but you also need sufficient vitamin C to produce enough L-carnitine [4].

Keto dieters often tout the benefits and supplement with L-carnitine for several reasons, including brain health, energy, and weight loss. People who exercise more regularly might need more carnitine for growth and development.

Generally speaking, 2 grams per day is considered a safe dosage free from serious side effects. One study showed people taking 3 grams daily for 21 days experienced no negative effects. Many people have reported benefits from taking higher doses [5].

What Are the Symptoms of L-Carnitine Deficiency?

Symptoms of L-carnitine deficiency include: 

  • Muscle cramps and weakness
  • Low energy levels
  • Sudden weight gain

Over time, more severe deficiencies could increase the risk of conditions like obesity, Alzheimer’s, diabetes, and cardiovascular disease.

Leg cramps from low l-carnitine

What Are the Benefits of Taking L-Carnitine on Keto?

Keto dieters and athletes supplement with L-carnitine to boost athleticism, weight loss, promote healthy aging, and more. L-carnitine could increase mitochondrial function [6].

There are different forms of L-carnitine available. Acetyl-L-carnitine is one of the more effective types for most people [7]. 

Brain Health

Acetyl-L-carnitine (ALCAR) is likely the most effective form for brain health and could be advantageous for those with neurodegenerative diseases and age-related mental decline [8] [9].

Studies indicate taking acetyl-L-carnitine every day helps reverse declining brain function linked to Alzheimer’s and other brain conditions. Similar benefits were observed in people without brain conditions [10] [11].

Heart and Circulation

Some studies demonstrate a reduction in blood pressure and inflammation associated with cardiovascular disease. One study showed a daily dose of 2 grams of acetyl-L-carnitine caused nearly a 10-point reduction in systolic blood pressure, which is a key indicator of cardiovascular health and disease risk. In the research, patients with coronary heart disease and chronic heart failure seem to improve with L-carnitine [12] [13].

Exercise Performance and Muscle Recovery

L-carnitine L-tartrate might reduce muscle soreness and improve recovery after exercise, and it’s commonly used in sports supplements because of its rapid absorption rate. It could also increase oxygen supply to your muscles along with blood flow and nitric oxide production [14] [15].

Weight Loss

Since L-carnitine moves fatty acids into your cells to be used for energy, it makes sense that it appears to work as a weight-loss supplement. L-carnitine is believed to improve your body’s ability to burn fat and lose weight. However, when it comes to weight loss, studies are mixed, with some showing success and others showing no difference [16] [17] [18].

Blood Sugar Issues and Type 2 Diabetes

L-carnitine could improve symptoms and risk factors of type 2 diabetes and reduce blood sugar levels [19] [20].

Should You Take L-Carnitine on Keto?

It’s up to you if you’d like to supplement with L-carnitine on keto. Especially if you have a health condition, questions, or concerns, or if you’re planning on supplementing for a longer period of time, it’s always best to talk to your doctor before making any diet or supplement changes.

Overall, L-carnitine is considered a safe supplement with a recommended daily dose of up to 2 mg. L-carnitine is a popular supplement in the keto and athletic communities, though studies show that it may or may not be effective for some uses.

Benefits of L-carnitine may include:

  • Brain health
  • Energy
  • Fat burning
  • Improved blood sugar and circulation
  • Weight loss
  • Improved muscle recovery and exercise performance.

Do you take L-carnitine on keto? Let us know!

Steph Green is a content writer specializing in and passionate about healthcare, wellness, and nutrition. Steph has worked with marketing agencies, written medical books for doctors like ‘Untangling the Web of Dysfunction,’ and her poetry book ‘Words that Might Mean Something.’ In 2016, after four years of struggling with her own health problems and painful autoimmune disease, Steph developed a life-changing and extensive knowledge of keto, nutrition, and natural medicine. She continues on her healing journey and enjoys helping others along the way.



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