All you need to know about carnitine
The amino acid carnitine is aptly named, its main source in our diet being meat-based foods. Although it’s not a nutrient essential for life, researchers have discovered a range of benefits from this amazing substance. Originally named Vitamin BT, it was discovered in the 1940s during research into, of all creatures, the meal worm. Unlike the meal worm, humans can synthesise carnitine from the combination of two amino acids, lysine and methionine. This is not always enough, however, and certain conditions benefit from either higher dietary intake or supplementation.
Carnitine in your body
Carnitine’s main function is in energy production. Energy is produced within every cell of your body in an area known as the mitochondria. Carnitine facilitates the transport of long-chain fatty acids into the mitochondria so the energy-producing oxidation of these fats can occur. It also has the added benefit of reducing lactic acid buildup, which often occurs after exercise and creates the sensation of soreness in muscles. The dual actions of boosting energy and reducing lactic make carnitine particularly useful for sportspeople.
However, carnitine is not only useful for those who are heavier exercisers. It seems that this substance can also help the average person to get in shape. This occurs through its ability to stimulate the use of fat over carbohydrates as fuel for your body. It also reduces muscle breakdown, so combined with exercise it can encourage muscle tone and fat reduction.
In 2008 one study showed even wider-ranging benefits for carnitine. It was found to be helpful for both obesity and the various symptoms associated with it known as Syndrome X. This research saw carnitine supplementation reduce the particularly dangerous visceral fat which sits around the internal organs as well as reducing levels of a substance called leptin that stimulates hunger. It was also found to reduce serum insulin along with unhealthy levels of fat in the blood and the liver. This has remarkable implications for obesity which is one of the fastest growing health conditions in Australia and New Zealand.
With its role in energy formation, it’s not surprising that carnitine is located largely in the areas requiring more a lot of energy: namely, your muscles. This includes your body’s most important muscle, the heart. In fact, one study found that carnitine improved blood flow and so the oxygenation of the heart, meaning a reduced chance of heart attacks.
Another important role of carnitine is in brain function. A recent study showed supplementation in rats led to significantly improved memory due to its antioxidant effect.
Also thought to be the result of carnitine’s strong antioxidant effect is its role in supporting chemotherapy-induced peripheral neuropathy. Research from 2006 showed its efficacy as a preventative and treatment for this very painful side effect.
Last, but with growing infertility as a societal issue, certainly not least, studies have indicated that carnitine may improve sperm motility. There is some debate over this effect but further research may confirm yet another role for this important nutrient.
Carnitine in action
Who needs it?
So how do you know if you need to increase your intake of carnitine? Certainly, anyone with the conditions mentioned above, from obesity to heart disease, can benefit. Effects can also be seen for those with greater levels of use such as athletes, people who have kidney disease and adrenal insufficiency and those who drink above a “healthy” level of alcohol.
Deficient or not, you may just decide to take in more carnitine to get in better shape. If this is your aim, though, remember that carnitine works with exercise to enhance its fat-loss and muscle-gaining effects. If you decide to just sit on the couch and take your supplement, you will probably find it is just as hard to get into your swimmers this season.
The best food sources are certainly red meats, but white meats and milk are also relatively high. If you are vegetarian, don’t despair, as carnitine can also be found in foods such as seeds and nuts, legumes and a range of greens.
If you decide to use a supplement for a therapeutic effect you must only use an L-carnitine source as opposed to a D-carnitine. The reason is this second type is not a natural form and has been found to be toxic. Taking 1-2g per day will give you a good boost and you’ll get the best results if it’s consumed on an empty stomach.
Rowena York is a naturopath, herbalist and nutritionist with a practice in Coffs Harbour on the mid-North Coast. She conducts nutritional counselling and specialises in stress and anxiety related conditions as well as digestive disorders.