The Health Benefits of L-Carnitine

L-Carnitine plays a role in many different processes in the body and has many benefits. Although it's main claim to fame is weight loss.

If you’re wondering whether an L-Carnitine supplement will help you shed those extra pounds, this article will give you some clarity in the light of scientific evidence.

We’ll also take a look at other health benefits of L-Carnitine, the recommended dosage, and the side effects you should expect.

Let’s begin!

What is L-Carnitine?

L-Carnitine is a naturally occurring amino acid derivative. Amino acids are the building blocks of proteins but the body can also convert them into L-Carnitine.

The main job of L-Carnitine in the body is to allow mitochondria to utilize fatty acids to make energy.

Mitochondria are the powerhouse of your cells but they’re surrounded by a selective membrane that does not allow substances to cross it freely. For mitochondria to make energy from a molecule, the molecule must be transported across their membrane.

For fatty acids, this transporter is called L-Carnitine, which allows them to cross the mitochondrial membrane and get converted into energy.

If you’re healthy, your kidney and liver make sufficient L-Carnitine for your needs. They do so by converting two amino acids — lysine and methionine — into carnitine. Small amounts of L-Carnitine can also be obtained via diet with pork, fish, chicken, milk, and beef being good dietary sources.

Since L-Carnitine can be naturally made by the body under healthy conditions, it’s called a conditionally essential nutrient. This means you only need to take a supplement if you have certain conditions — such as kidney failure — that hamper carnitine’s production.

But some health-oriented people still prefer to take carnitine supplements to make sure their body has an ample amount for optimal functioning. So let’s take a look at them now.

Health Benefits of L-Carnitine

L-Carnitine can help you lose weight

Since carnitine transports fatty acids into the mitochondria so they can get converted into energy, it makes sense to think they would help you lose weight by burning fat.

However, you should know that the evidence on this matter is mixed.

For example, in a review of 9 studies looking at older or obese individuals, it was found that people taking L-Carnitine lost an average of 1.3 kg.

But other studies have failed to demonstrate this effect. In a study with 38 women who were followed as they exercised 4 times a week, L-Carnitine did not improve weight loss in those who took it versus those who didn’t.

This means while L-Carnitine has the potential to aid in weight loss, we don’t really know for sure if it will work for you. This is especially true if you’re young because L-Carnitine’s weight loss effect has not been demonstrated in this population.

If you’re looking to lose weight, exercise and dietary changes are probably your best bet right now. You can throw an L-Carnitine supplement into the mix and see if it helps, but relying completely on a supplement is not advised.

Benefits the cardiovascular system

L-Carnitine has been shown to provide two main cardiovascular benefits:

• It reduces heart failure in patients with severe conditions like coronary artery disease
• It reduces systolic blood pressure. High blood pressure is a significant risk factor for heart disease.

Helps you exercise longer

L-Carnitine supplements are popular among athletes. Carnitine has been shown to improve the following:

• Muscle oxygen supply
• Muscle blood flow via the production of nitric oxide, which dilates blood vessels
• Red blood cell count, which transports oxygen to muscles
• Post-exercise muscle soreness

L-Carnitine may help patients through chemotherapy

Weakness and fatigue are two of the most uncomfortable chemo side effects and L-carnitine may help reduce their severity.

One reason for this may be the fact that chemotherapy has been shown to reduce L-carnitine levels in the body.

Research is still going on the topic and it’s difficult to say anything conclusively.

L-carnitine may reduce blood sugar levels in type 2 diabetes

Type 2 diabetes occurs when the body stops responding to insulin, which leads to high blood sugar levels.

High blood sugar is the major cause of complications seen in diabetes and carnitine supplements may counter this.

This study on patients with diabetes type 2 demonstrates a significant reduction in sugar levels in those who took carnitine.

Nonetheless, you should know that carnitine is not currently used by doctors to treat diabetes type 2. Weight control and the anti-diabetic drug metformin still remain the first-line treatments.

L-carnitine may halt the decline in brain function

Cognitive decline is a common cause of morbidity in the elderly and those with neurodegenerative diseases like Alzheimer’s. And the acyl form of L-carnitine — acetyl-L-carnitine (ALCAR) — has been shown to slow cognitive decline in both these scenarios.

Cognitive impairment due to alcoholism may also be improved with carnitine. For example, in this study with people addicted to alcohol, 2 grams of ALCAR for 90 days improved all areas of brain function.

However, more studies are needed to determine whether L-carnitine can be used by healthy individuals to prevent cognitive decline.

However, keep in mind that the evidence for all these benefits is mixed. Also, these effects of L-carnitine may take weeks or months to kick in, so you shouldn’t expect immediate improvement in exercise after starting a supplement.

What are the side effects and safe dosage of L-carnitine?

L-carnitine supplements are generally considered safe when taken under the recommended dosage of up to 2 grams per day. You may experience mild GI side effects like nausea, vomiting, and diarrhea. In some cases, people may develop a fishy body odor.

The only concern about long-term L-carnitine usage is atherosclerosis. L-carnitine has been shown to increase the levels of a molecule called trimethylamine-N-oxide (TMAO). And TMAO can lead to fat deposits in your arteries, leading to atherosclerosis.

If you already suffer from atherosclerosis, consult a doctor before starting L-carnitine.

Finally, L-carnitine has been shown to interact with certain medications, including anti-seizure drugs and antibiotics. It’s a good idea to consult a doctor before starting carnitine if you’re on medications.