Can L-Carnitine Help You Lose Weight and Build Power?

What is L-carnitine

L-carnitine (levocarnitine) is a nitrogenous acid that presentCarnitine / The Office of Dietary Supplements (ODS) of the National Institutes of Health (NIH) in almost all cells of the body. Especially a lot of this organic compound in skeletal muscles and myocardium.

L-carnitine transports long-chain fatty acids across the membrane of mitochondria, the organelles that oxidize compounds to release energy. In other words, it delivers fuel to the "energy stations" of the cells.

In addition, this acid cleans out the toxic waste products of organelles, preventing the accumulation of "garbage".

Most healthy people are not deficient in L-carnitine because it is ingested in the diet and is also made in the liver and kidneys from the amino acids lysine and methionine.

Deficiency occurs in rare cases, such as kidney failure or certain antibiotics.

Does L-carnitine really help you lose weight?

Supplements with L-carnitine are positioned as a means for weight loss and are part of many "fat-burning" complexes.

Since this substance helpsA. E. Jeukendrup, R. Randell. Fat burners: nutrition supplements that increase fat metabolism / Obesity Reviews use long-chain fatty acids as fuel for muscles, it is suggested that regular intake may increase fat oxidation.

At the same time, several studies have shown that even large doses of L-carnitine - up to 6 g for two weeks - do not change1. M. D. Vukovich, D. L. Costill, W. J. fink. Carnitine supplementation: effect on muscle carnitine and glycogen content during exercise / Medicine and science in sports and exercise
2. C. Barnett, D. L. Costill, M. D. Vukovich. Effect of L-carnitine supplementation on muscle and blood carnitine content and lactate accumulations during high-intensity sprint cycling / International journal of sport nutrition its concentration in the muscles, do not affect the oxidation of fats and do not increaseR. G. Villani, J. Gannon, M. self. L-Carnitine supplementation combined with aerobic training does not promote weight loss in moderately obese women / Sport nutrition and exercise metabolism energy expenditure at rest or during exercise.

The only way the muscles can store more L-carnitine is by taking it with carbohydrates. Insulin makesF. b. Stephens, D. Constantin-Teodosiu, D. Lifetime. Insulin stimulates L-carnitine accumulations in human skeletal muscle / FASEB journal: official publication of the Federation of American Societies for Experimental Biology. the body to increase the reserves of this compound, but in the context of losing weight, this approach is irrational.

The fact is that even if you slightly increase fat oxidation in the long run, a calorie surplus and a high insulin won't let you shed those extra pounds.

And yet in analysisM. Pooyandjoo, M. Knowhi, S. Shab Bidar. The effect of (L-)carnitine on weight loss in adults: a systematic review and meta-analysis of randomized controlled trials / Obesity reviews 9 scientific studies have concluded that taking L-carnitine helps to lose an average of 1.33 kg. True, all scientific studies involved people who were obese or very overweight, and in 5 out of 9 studies, participants had diabetes.

In more recent meta-analysisN. Talenezhad, M. Mohammadi, N. Ramezani-Jolfaie. Effects of l-carnitine supplementation on weight loss and body composition: A systematic review and meta-analysis of 37 randomized controlled clinical trials with dose-response analysis / Clinical nutrition ESPEN 37 scientific papers noted that taking L-carnitine can reduce weight by an average of 1.2 kg, but does not have a significant effect on waist circumference, body mass index and body fat percentage.

Thus, the supplement will help to lose weight quite a bit only for obese and overweight people. And if your BMI is in the normal range and you want to “dry out” or get rid of belly fat, L-carnitine is unlikely to help with this.

Can L-carnitine improve performance in sports?

AT meta-analysisJ. Mielgo-Ayuso, L. Pietrantonio A. Viribay. Effect of Acute and Chronic Oral L-Carnitine Supplementation on Exercise Performance Based on the Exercise Intensity: A Systematic Review / Nutrients 11 studies have found that taking L-carnitine can actually increase performance, but only when working with high intensity. Moreover, you can take the supplement both once and for a long time.

The studies reviewed in the analysis found that:

• Six months of taking 2.7 g of the supplement per day along with 160 g of carbohydrates improvesb. T. Wall, F. b. Stephens, D. Constantin Teodosiu. Chronic oral ingestion of L-carnitine and carbohydrate increases muscle carnitine content and alters muscle fuel metabolism during exercise in humans / The Journal of physiology results in very intensive work on a bicycle ergometer (80% of the maximum oxygen consumption, IOC).
• 9 weeks of taking 2 g of L-carnitine per day increaseM. S. Koozehchian, A. Daneshfar, E. Fallah. Effects of nine weeks L-Carnitine supplementation on exercise performance, anaerobic power, and exercise-induced oxidative stress in resistance-trained males / Journal of Exercise Nutrition & biochemistry the number of repetitions in strength exercises, the total volume of training and peak power in work on a bicycle ergometer.
• Take 3 g supplement 1.5 hours before test increasesP. L. Jacobs, E. R. Goldstein, W. blackburn. Glycine propionyl-L-carnitine produces enhanced anaerobic work capacity with reduced lactate accumulation in resistance trained males / Journal of the International Society of Sports Nutrition peak power in sprints on a bicycle ergometer.
• Taking 3-4 g of L-carnitine one hour before exercise helpsG. Orer, N. Guzel. The Effects of Acute L-carnitine Supplementation on Endurance Performance of Athletes / Journal of Strength and Conditioning Research slow down the accumulation of lactate and delay the onset of fatigue when running at different speeds - from 8 to 17 km / h.

However, in less intense exercise, creatine supplementation does not provide any performance benefits.

Does L-carnitine really speed up recovery after exercise?

There is some evidence that L-carnitine may promote recovery by acting as an antioxidant.

Yes, in one researchK. Parandak, H. Arazi, F. Khoshkhahesh. The Effect of Two-Week L-Carnitine Supplementation on Exercise -Induced Oxidative Stress and Muscle Damage / Asian journal of sports medicine Two weeks of supplementation at 2g per day before a 14K race helped young men recover faster.

The group that drank a course of L-carnitine significantly improved the overall antioxidant defense of the body, and a day after a heavy load, there were significantly fewer enzymes indicating damage muscles.

The same was noted in another experimentW. J. Kramer, J. S. Volek, D. N. French. The effects of L-carnitine L-tartrate supplementation on hormonal responses to resistance exercise and recovery / Journal of strength and conditioning research with a similar design. Only in it, instead of running, strength exercises were used. Young men who consumed L-carnitine for three weeks had far less muscle damage after 5 sets of 15-20 squats.

Assistance in recovery was noted in another experimentJ. Ho, W. J. Kramer, J. S. Volek. l-Carnitine l-tartrate supplementation favorably affects biochemical markers of recovery from physical exertion in middle-aged men and women / Metabolism, now with the participation of men and women 45-50 years old. A three-week course of taking 2 g of L-carnitine per day helped them recover faster from strength training and suffer less from muscle pain.

But despite the encouraging results, it is too early to recognize L-carnitine as an effective recovery aid. At least until at least one meta-analysis is done.

Can L-carnitine hurt?

Three-gram dose of L-carnitine per day maybeR. Fielding, L. Riede, J. P. Lugo. l-Carnitine Supplementation in Recovery after Exercise / Nutrients cause nausea and vomiting, abdominal pain, diarrhea, and a fishy body odor.

Yes, in one researchR. G. Villani, J. Gannon, M. self. L-Carnitine supplementation combined with aerobic training does not promote weight loss in moderately obese women / Sport nutrition and exercise metabolism five women taking the 2g supplement twice daily left the study early due to nausea and diarrhea.

Another possible side effect tiedA. K. Sawicka, G. Renzie, R. A. Olek. The bright and the dark sides of L-carnitine supplementation: a systematic review / Journal of the International Society of Sports Nutrition with an excess of trimethylamine oxide (TMAO) - a product of the processing of carnitine by intestinal bacteria.

It is believed that a large number maybeR. A. Koeth, Z. Wang, b. S. Levison. Intestinal microbiota metabolism of L-carnitine, a nutrient in red meat, promotes atherosclerosis / Nature medicine increase the risk of atherosclerosis and other diseases of the cardiovascular system, and therefore an excess of L-carnitine in the diet is undesirable, especially for those who consume a lot of red meat.

Who Should Try L-Carnitine

You can try this supplement if you:

1. Are obese and trying to lose weight. At the same time, keep in mind that L-carnitine can provide only a small weight loss - within 1 kg. Via diets and exercises can be thrown off much more.
2. Do sports associated with high-intensity loads - more than 80% of the IPC. The supplement can increase power and delay time to fatigue.
3. Looking for a way to recover faster after heavy loads.

If you do not have a lot of excess weight, and physical activity is of low intensity, supplements with L-carnitine will be useless.

Which L-carnitine to choose and how to drink it

Several forms of supplements are sold on the sports nutrition market: L-carnitine L-tartrate (mixed with tartaric acid), as well as acetyl-L-carnitine and propionyl-L-carnitine.

According to the data experimentY. Cao, Y. Wang, C. Liu. Comparison of pharmacokinetics of L-carnitine, acetyl-L-carnitine and propionyl-L-carnitine after single oral administration of L-carnitine in healthy volunteers / Clinical and investigative medicine, the last two forms are inferior to pure carnitine in terms of absorption rate and are more quickly excreted from the body.

Moreover, in one researchD. Wang, T. Wang, Y. Yang. The Effects of L-Carnitine, Acetyl-L-Carnitine, and Propionyl-L-Carnitine on Body Mass in Type 2 Diabetes Mellitus Patients / Frontiers in Nutrition calculated that only L-carnitine L-tartrate provides any effect on the weight of people with type 2 diabetes, while acetyl and propionyl do not.

Regarding the effect on athletic performance, most studies use L-carnitine L-tartrate, so that if you want to increase power, delay fatigue or speed up recovery, you should choose this additive.

As for the dosage, most manufacturers suggest taking 2 g per day. And given the possible side effects, it is worth following their recommendations.