No significant effect was seen for waist circumference ( WC ) and body fat percent .
A non-linear dose-response association was seen between l-carnitine supplementation and body weight reduction ( P < 0.001 ) suggesting that ingestion of 2000 mg l-carnitine per day provides the maximum effect in adults .
This association was not seen for BMI , WC and body fat percent .
CONCLUSIONS l-carnitine supplementation provides a modest reducing effect on body weight , BMI and fat mass , especially among adults with overweight/obesity
BACKGROUND AND AIM Clinical evidence which investigated the effects of l-carnitine , a vitamin-like substance , on weight loss had led to inconsistent results .
This study therefore aim ed to examine the effect of l-carnitine supplementation on body weight and composition by including the maximum number of r and omized controlled trials ( RCTs ) and to conduct a dose-response analysis , for the first time .
Effects of Oral L-Carnitine Administration in Narcolepsy Patients: A Randomized, Double-Blind, Cross-Over and Placebo-Controlled Trial
Narcolepsy is a sleep disorder characterized by excessive daytime sleepiness , cataplexy , and rapid eye movement ( REM ) sleep abnormalities . A genome-wide association study ( GWAS ) identified a novel narcolepsy-related single nucleotide polymorphism ( SNP ) , which is located adjacent to the carnitine palmitoyltransferase 1B ( CPT1B ) gene encoding an enzyme involved in β-oxidation of long-chain fatty acids . The mRNA expression levels of CPT1B were associated with this SNP . In addition , we recently reported that acylcarnitine levels were abnormally low in narcolepsy patients . To assess the efficacy of oral l-carnitine for the treatment of narcolepsy , we performed a clinical trial administering l-carnitine ( 510 mg/day ) to patients with the disease . The study design was a r and omized , double-blind , cross-over and placebo-controlled trial . Thirty narcolepsy patients were enrolled in our study . Two patients were withdrawn and 28 patients were included in the statistical analysis ( 15 males and 13 females , all with HLA-DQB1 * 06:02 ) . l-carnitine treatment significantly improved the total time for dozing off during the daytime , calculated from the sleep logs , compared with that of placebo-treated periods . l-carnitine efficiently increased serum acylcarnitine levels , and reduced serum triglycerides concentration . Differences in the Japanese version of the Epworth Sleepiness Scale ( ESS ) and the Medical Outcomes Study 36-Item Short-Form Health Survey ( SF-36 ) vitality and mental health subscales did not reach statistical significance between l-carnitine and placebo . This study suggests that oral l-carnitine can be effective in reducing excessive daytime sleepiness in narcolepsy patients . Trial Registration University hospital Medical Information Network ( UMIN )
No significant effect was seen for waist circumference ( WC ) and body fat percent .
A non-linear dose-response association was seen between l-carnitine supplementation and body weight reduction ( P < 0.001 ) suggesting that ingestion of 2000 mg l-carnitine per day provides the maximum effect in adults .
This association was not seen for BMI , WC and body fat percent .
CONCLUSIONS l-carnitine supplementation provides a modest reducing effect on body weight , BMI and fat mass , especially among adults with overweight/obesity
BACKGROUND AND AIM Clinical evidence which investigated the effects of l-carnitine , a vitamin-like substance , on weight loss had led to inconsistent results .
This study therefore aim ed to examine the effect of l-carnitine supplementation on body weight and composition by including the maximum number of r and omized controlled trials ( RCTs ) and to conduct a dose-response analysis , for the first time .