L-Carnitine and Increased Serum Total Protein Levels

Across 3 studies, all reported beneficial effects of L-carnitine on serum total protein levels, with effect sizes ranging from moderate to large and a predominant moderate effect. The evidence comes from clinical populations with kidney disease or critical illness, with study durations ranging from 7 days to 1 year (median ~6 months). Dosing was only specified in one study (3 g/day), so no consistent dose range can be identified.

• Studied populations: patients with kidney disease (including those on maintenance hemodialysis with malnutrition) and critically ill patients in the ICU

Caveats: Available evidence is overwhelmingly positive — clinical literature in this area is subject to publication bias (null-result studies are less likely to be published or indexed). Evidence base is small (only 3 studies) — conclusions should be considered preliminary. All studies were conducted in specific clinical populations, so generalizability to healthy individuals is uncertain. Study durations varied widely (7 days to 1 year), and one study did not report the dose administered.