Acetyl-L-Carnitine (ALCAR)

Tier 2 — promising · Cognitive aging · Neuropathy

A form of carnitine that crosses the blood-brain barrier, supporting memory and cognition in older adults. Multiple reviews confirm it significantly improves thinking in mild cognitive decline. Also reduces nerve pain (numbness, tingling) in diabetic neuropathy. Can cause insomnia if taken in the evening. Note: this is NOT the same as L-carnitine supplements used for fat burning.

Dose: 1,500–2,000 mg/day in 2–3 divided doses; morning and midday only (avoid evening — stimulating)