However, more research is needed to confirm most of these claims.
L-carnitinealso known as levocarnitineis an amino acid that your body makes naturally.
It can also be taken in supplement form.
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It is important to remember, however, that supplements are not appropriate for everyone.
The modest weight reduction was primarily seen in people who also ate a low-calorie diet and exercised.
There was less evidence of improved body fat percentage, according to a 2020 analysis of L-carnitine research studies.
A study from 2017 found benefits from L-carnitine supplementation in people with chronicheart failure.
Improvements in several areas of heart function included cardiac output andleft ventricular ejection fraction.
Intermittent claudication is a form of PAD that is characterized by pain in the lower limbs.
Lastly, L-carnitine has been studied for its effects on cholesterol levels.
Kidney Disease
People receiving peritoneal dialysis treatment for renal (kidney) failure often demonstrate L-carnitine deficiency.
More research is needed to understand this use.
Neurological Illnesses
Alzheimer’s diseaseis the most common key in of dementia.
Researchers have studied L-carnitine to determine if it can help produce acetylcholine.
Further research is needed on the effects of L-carnitine on people with Alzheimer’s disease.
Study authors included studies where participants took oral L-carnitine supplements for at least seven days.
Early studies suggest a benefit, but more studies are needed before the association is fully understood.
However, research has had mixed results as to whether L-carnitine supplements improve physicalexerciseperformance.
Several supplements, including L-carnitine, have been studied for their effects on erectile dysfunction (ED).
Acetyl L-carnitine and propionyl-L-carnitine are available in supplement form.
Lastly, L-carnitine may help improve testosterone levels, according to at least one study.
However, the study authors did not disclose specifically what was in the nutrient treatment.
Thyroid Disorders
L-carnitine may play a role in the treatment of thyroid disorders.
A 2024 study investigated fatigue levels in people with chronic fatigue syndrome (CFS) or hypothyroidism.
About 20% of hypothyroidism patients have CFS even when they are on medication.
The study found a link between low L-carnitine levels, low serotonin levels, and fatigue.
The study authors suggest that elevating serotonin levels to a normal range with L-carnitine may help reduce fatigue.
If you have hypothyroidism and are taking medication, speak to your provider before taking L-carnitine supplements.
Carnitine may prevent thyroid hormone from getting into cells, and could make thyroid hormone replacement less effective.
L-carnitine has also been studied for its effects on hyperthyroidism.
They added, however, that more research is needed.
Dietary Sources of L-Carnitine
The best source of L-carnitine is in food.
The body’s ability to absorb L-carnitine in food is much higher than in a supplement.
There are several forms of carnitine available for supplementation.
When administered through an IV, the supplement should only be given under the care of a healthcare professional.
Daily Dosage
Carnitine is made in the liver, kidney, and brain.
The body stores 95% of carnitine in the heart and skeletalmuscles.
However,people who follow a vegan dietwill likely consume only 1.2 mg per day.
Oddly, diet does not seem to influence how much carnitine the body makes.
Since carnitine is not considered an essential nutrient, there are no recommended daily amounts for supplements.
Side Effects and Warnings
L-carnitine is generally considered safe when consumed in food.
But there are some side effects and concerns to be aware of.
If you take more than 3 grams per day, you may also notice a fishy body odor.
There are potential side effects when too much L-carnitine is taken.
They include:
Always talk to a healthcare provider before starting a carnitine supplement.
Who Can Benefit from Supplements?
Who Should Not Take L-Carnitine Supplements?
But more research is needed to fully understand the interactions.
If you are taking one of these medications, speak to your healthcare provider before taking L-carnitine.
As a result, some supplement products may not contain the ingredients listed on the label.
It produces energy and removes toxins from the cells.
L-carnitine is often advertised as a supplement to help weight loss, improve physical performance, and more.
Research still needs to be done to confirm the effectiveness of L-carnitine supplementation.
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