L-carnitine is an amino acid produced by the body that’s also found in food and supplements. Some studies suggest it may offer some health benefits, including increased weight loss, improved brain function, and more.
L-carnitine is a naturally occurring amino acid derivative that’s often taken as a supplement. It is used for weight loss and may have an impact on brain function.
However, popular claims about supplements don’t always match up with the science.
What is L-carnitine?
L-carnitine is a nutrient and dietary supplement. It plays a crucial role in the production of energy by transporting fatty acids into your cells’ mitochondria.
The mitochondria act as engines within your cells, burning these fats to create usable energy. Your body can produce L-carnitine out of the amino acids lysine and methionine.
For your body to produce it in sufficient amounts, you also need plenty of vitamin C.
In addition to the L-carnitine produced in your body, you can also obtain small amounts by eating animal products like meat or dairy products.
Vegans or people with certain genetic issues may be unable to produce or obtain enough. This makes L-carnitine a conditionally essential nutrient.
L-carnitine is the standard biologically active form of carnitine, which is found in your body, foods, and most supplements.
Here are several other types of carnitine:
- D-carnitine: This inactive form has been shown to reduce blood levels of carnitine and increase fat buildup, leading to liver inflammation and oxidative stress.
- Acetyl-L-carnitine: Often called ALCAR, this is possibly the most effective form for your brain. Studies suggest that it may benefit people with neurodegenerative diseases.
- Propionyl-L-carnitine: This form is well-suited for circulatory issues, such as peripheral vascular disease and high blood pressure. According to some older research, it may boost the production of nitric oxide, which improves blood flow.
- L-carnitine L-tartrate: This is commonly added to sports supplements due to its rapid absorption rate. It may aid muscle soreness and recovery in exercise.
For most people, acetyl-L-carnitine and L-carnitine seem to be the most effective for general use. However, you should always pick the form that’s best for your personal needs and goals.
Role in your body
L-carnitine’s main role in your body involves mitochondrial function and energy production.
In cells, it helps transport fatty acids into the mitochondria, where they can be burned for energy.
More than 95% of your L-carnitine stores are contained in your muscles, along with trace amounts in your blood, liver, heart, and kidneys.
L-carnitine may help increase mitochondrial function, which plays a key role in disease and healthy aging.
Newer research illustrates the potential benefits of carnitine’s different forms, which may be used for various conditions, including heart and brain diseases.