Carnitine is one of the key ingredients in dietary supplements for weight loss. This is due to the virtues attributed to it for its potential action on energy metabolism and the transport of fatty acids. But its action is not limited to slimming the figure, this molecule has many other beneficial effects that are less well known. In particular its role in recovery, performance improvement and even the stimulation of cognitive functions. Here is a 4-point review of this molecule of interest and our advice on the use of carnitine-based supplements.
Carnitine
Carnitine is an amino acid derivative found in various forms in food supplements:L carnitine, carnitine L tartrate, acetyl L carnitine. . . But is carnitine supplementation necessary?
Carnitine is not an essential amino acid because the body has the ability to synthesise it naturally in the liver and kidneys from lysine and methionine combined with various vitamins and enzymes. It is naturally present in animal products, particularly meat, and its consumption generally helps the body to maintain levels that allow it to function properly.
However, it is common for people following a vegan diet that natural production is not sufficient to meet the body's needs, in which case carnitine supplementation is recommended.
But in higher, concentrated doses, carnitine can also have beneficial effects on both physical performance and health.
The benefits of carnitine
Weight loss
Carnitine's main role is in mitochondrial function. Mitochondria are small organelles that are essential for cellular energy processes. In other words, they are small factories in the cells whose role is to convert substrates such as carbohydrates and fats into energy.
And the function of carnitine is to transport fatty acids into the mitochondria where they can be converted into energy. Muscles are very demanding in terms of energy, which is why almost all of the body's carnitine is stored in the muscles.
By playing a role in the metabolism and transport of fatty acids into the mitochondria to be converted into energy, this implies that a supply of carnitine would accelerate the burning of fat.
Indeed, a published study of 600 overweight people concluded that taking 1g of L carnitine for 30 days enabled overweight or obese people to lose weight when this protocol was coupled with physical activity.
People with high body fat have a high need for Carnitine to transport the destocked fatty acids to the mitochondria in the muscle cells. This study showed that creatine consumption was most effective after the age of 30, perhaps because after that age, endogenous creatine synthesis decreases and therefore supplementation is all the more important 1.
Performances physiques
Carnitine is also of interest for improving sports performance. But its action is not always direct or immediate.
It can indeed act in different ways:
- Taking carnitine increases the production of red blood cells, which are essential for transporting oxygen. So it allows a better supply of the muscles and allows to gain in muscular endurance.
- A published study has shown that carnitine is also able to reduce muscle soreness after exercise. This is due to its ability to increase the production of nitric oxide, which leads to vasodilatation and therefore a better supply of nutrients to the muscle cells, but above all to the evacuation of metabolic waste. It is therefore an interesting ally for the phases of muscle recovery.
Fonction cérébrale
Carnitine has been extensively studied for its potential effect on improving cognitive function and the development of Alzheimer's disease.
The form that seems to have shown the most positive effects is acetyl L carnitine. Because unlike carnitine l tartrate (or other forms), it is easily absorbed in the intestine and easily passes the blood-brain barrier.
An intake of 1. 5 to 3 grams of l carnitine (Acetyl) can improve brain function in people with Alzheimer's disease 3. But the mechanism is not yet well studied. This may be because it improves mitochondrial activity in the brain, or because of a potential ability to increase the synthesis of the neurotransmitter acetyl choline 3.
Side effects
The recommended daily dose not to be exceeded for prolonged use is 2 grams of l carnitine. Beyond this dose, side effects that have been reported are stomach upset, nausea and diarrhoea 4.
Carnitine should not be used by anyone with liver or kidney problems, diabetes, high blood pressure or other medical conditions. It is best to consult a health care practitioner to determine if this supplement is compatible with any treatment or condition.
Although it is generally known to be safe for health. There is still a lack of information and studies on the potential harmful effects of high doses of carnitine.
When to use it
As you can see, carnitine helps to lose weight. Therefore, you should use this food supplement during a dry phase. On training days, it may be wise to consume this supplement just before the physical exercise. Since this is when your muscles need the most energy and will therefore need optimal use of body fat to produce energy.
This will allow you to better manage your training and potentially improve your sports performance and muscle recovery.
On off days, or without training, you can use carnitine in the morning on an empty stomach or at breakfast time if you have a sensitive stomach. It is always preferable to use this supplement with regular physical activity as this increases its effectiveness.
bibliography
1 Effects of L-Carnitine (Neutraceutical) In Weight Management among Overweight and Obese Adults of Age between 20 - 45yrs - A Comparative Study in Chennai and Tirupathi. International Journal of Scientific and Research Publications, Volume 2, Issue 9, September 2012
Giamberardino MA, Dragani L, Valente R, et al (1996) Effects of prolonged l-carnitine administration on delayed muscle pain and CK release after eccentric effort. Int J Sports Med 17, 320-324 Scott D. Mendelson M. D. Nutritional supplements and metabolic syndrome. Metabolic Syndrome and Psychiatric Illness, 2008
4. https://www. webmd. com/vitamins-and-supplements/acetyl-l-carnitine-uses-risks#1
5. https://www. drugs. com/sfx/l-carnitine-side-effects. html
