Jan 25, 2026Acetyl-L-Carnitine (ALCAR) and Brain Aging: Evidence, Mechanism, and Nerve HealthAcetyl-L-carnitine (ALCAR) crosses the blood-brain barrier and supports acetylcholine synthesis and mitochondrial function in neurons. Evidence supports mild cognitive decline and peripheral neuropathy. ALCAR differs importantly from L-carnitine in CNS access.