l carnitine's primary supposed ergogenic effect is that it might The effects of L-carnitine supplementation on lipid profiles in adults: A systematic review and dose-response meta-analysis L-Carnitine | Linus Pauling Institute
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[DOI] [PMC free article] [PubMed] [Google Scholar] 6

l-Carnitine improves endocrine function and folliculogenesis by reducing inflammation, oxidative stress and apoptosis in mice following induction of polycystic ovary syndrome

If your only symptom is weight gain, you probably have something other than a thyroid problem

: Ferreira GC, McKenna MC

Acetyl-l-carnitine, and propionyl-l-carnitine can be converted to levocarnitine by the body
