ABSTRACT
<p><b>OBJECTIVE</b>Carnitine, the only carrier for fatty acid to enter mitochondria for oxidation, has significant effects on serum lipids metabolism and male fertility. This study aimed to investigate the correlation of serum carnitine levels with sex and age among healthy Chinese adults in Nanjing.</p><p><b>METHODS</b>We obtained fasting blood samples from 347 healthy Chinese adults in Nanjing (182 males, 165 females, aged from 20 to 89), determined the levels of serum free, acylcarnitine and total carnitine by high performance liquid chromatography with pre-column ultraviolet derivatization, and analyzed the correlation of serum carnitine levels with the age and sex of the subjects.</p><p><b>RESULTS</b>Total and free carnitine levels were significantly higher in the males than in the females (P < 0.05) while no statistically significant differences were found in the acylcarnitine level (P > 0.05). Among those aged between 20 to 50 years, levels of serum free and total carnitine were significantly higher in men than in women (P < 0.05) and they increased with age in females, but with no significant differences between males and females older than 50 years. The acylcarnitine level showed no obvious differences in any age and sex groups.</p><p><b>CONCLUSION</b>Serum free and total carnitine levels are correlated with sex and age in healthy adults.</p>