When should L-carnitine be used to enhance weight loss? Is taking L-carnitine supplementation an effective way to burn fat? Are there any issues when using L-carnitine for weight loss? This article will look at the pros and cons of using this supplement and most importantly illustrate if it is worth spending your hard earned money on!

What is L-carnitine?

L-carnitine is a non-essential (sometimes conditionally-essential) amino acid that is involved in the transfer of fatty acids into mitochondria, which are involved in producing energy essentially.

What is the dosage?

To get the optimal benefits of L-carnitine it is recommended you take it daily for a number of weeks and then you may see some decent results. The recommended dosage for weight loss or performance enhancement would be 2-4g of L-carnitine per day, but does this supplement really have any noticeable effects in boosting exercise performance and increasing metabolism for weight loss?

L-carnitine for weight loss.

Some studies have shown taking L-carnitine supplementation daily can increase the concentration of this amino acid in the muscles and blood stream, which is said to possibly enhance fat metabolism.

In a study published in The Journal of Physiology, L-carnitine was said to spare glycogen (a readily available form of stored energy) by utilizing more fat.

However it is thought that supplements and energy drinks containing L-carnitine, which claim to be metabolic enhancers helping you to lose weight and improve your athletic performance are not as effective as some may suggest, as no scientific data actually backs up these claims.

Incidentally, taking L-carnitine may result in you losing your good health rather than those extra pounds, which I will explain below.

The word carnitine is derived from the Latin word for flesh: carnis and this is also the root of the word carnivore. The liver and kidneys manufacture carnitine from two amino acids, lysine and methionine. Carnitine is then stored in your brain, heart and skeletal muscles.

Carnitine plays a crucial role in your body, it aids in transporting long-chain fatty acids into the cells’ mitochondria, where they generate energy. It also escorts toxic by-products of energy production out of the cells, so they do not accumulate as toxic levels in the body.

L-carnitine for weight loss2

The National Institutes of Health (NIH) advises healthy adults and children do not need to take L-carnitine supplementation, plus The Institute of Medicine does not recommend any dietary allowance of carnitine. The body is quite capable of making enough of this actually, so where is the need for supplementation here?

In addition to this Carnitine is also found in a number of foods, mostly in red meat. The more red the meat, the more carnitine it contains in fact. Smaller amounts of carnitine are also present in fish, poultry, and dairy products.

The claims that L-carnitine supplementation can boost weight loss or athletic performance are fairly worrying when the contrary suggests L-carnitine supplementation has potential side effects such as diarrhoea, cramps nausea and vomiting.

Extra caution must be demonstrated when it comes to taking L-carnitine supplementation in people with kidney disease or seizure disorders. Supplements or energy drinks containing this, such as Monster Energy or any other energy drinks containing this may lead to muscle weakness in people with kidney disease and seizures in people who have a seizure disorder.

An even more serious complication associated with L-carnitine is its possible link to an elevated risk of developing heart disease. Some research points to a metabolite of carnitine increasing your chances of developing atherosclerosis, or hardening of the arteries. Carnitine is not directly responsible for this happening.

It is when carnitine encounters the bacteria living in the intestines. Every time you eat a steak or take an L-carnitine supplement, these bacteria in the gut produce a product called trimethyl amine. The liver then converts this trimethyl amine into trimethylamine N-oxide (TMAO).

This by product is what is thought to be responsible for clogging up your arteries, so at the expense of losing a few pounds you could be at risk of a heart attack!b

This could now make you think twice about tucking into that third steak and chips this week, or popping yet another one of those L-carnitine supplements.

These findings are based on taking quite a high dose of this supplement and limited studies on both sides of the L-carnitine fence, plus there are many health benefits believed to derived from taking L-carnitine such as prevention of mental health issues such as Alzheimer’s and management of Diabetes, neural problems and male fertility, so I will leave you to make up your own mind!

Article written by Claire Ward.

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