Most oral L carnitine supplements are glorified flavored chemical waters., , Low bioavailability = very little of it actually gets picked up for use by the body., , So when companies sell $40$60 Nanoparticle mediated L carnitine delivery for improved male fertility ScienceDirect Enhanced Bioavailability of L Carnitine After Painless Intradermal Delivery vs. Oral Administration in Rats Pharmaceutical Research Springer Nature Link Frontiers L carnitine prevents lenvatinib induced muscle toxicity without impairment of the anti angiogenic efficacy L carnitine supplements bioavailability is very less and according to some studies it takes 8 to 12 weeks for for loss results, so if you decide to supplement with oral L carnitine do take it in Low Bioavailability and High TMAO Production: Novel Insights Into Acetylcarnitine and Carnitine Metabolism KrimsDavis 2025 Molecular Nutrition & Food Research Wiley Online Library