Vitamin B12 deficiency history and symptoms

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

Overview

Tiredness
Decreased mental work capacity
Decreased concentration and memory
Irritability and depression
Sleep disturbances because B12 involved in the regulation of the sleep wake cycle by the pineal gland (through melatonin).^[1]

Sensory disturbances due to damage to peripheral nerves caused by demyelination and irreversible nerve cell death
Numbness
Tingling
Ataxic gait
Subacute combined degeneration of spinal cord
mania and psychosis.^[2]^[3]
Bipolar disorder appears to genetically co-segregate with the hereditary B12-deficiency disorder pernicious anemia.^[4]^[5]

↑ Hashimoto S, Kohsaka M, Morita N, Fukuda N, Honma S, Honma K (1996). “Vitamin B12 enhances the phase-response of circadian melatonin rhythm to a single bright light exposure in humans”. Neurosci. Lett. 220 (2): 129–32. PMID 8981490.
↑ Sethi NK, Robilotti E, Sadan Y (2005). “Neurological Manifestations Of Vitamin B-12 Deficiency”. The Internet Journal of Nutrition and Wellness. 2 (1).
↑ Masalha R, Chudakov B, Muhamad M, Rudoy I, Volkov I, Wirguin I (2001). “Cobalamin-responsive psychosis as the sole manifestation of vitamin B12 deficiency”. Israeli Medical Association Journal. 3: 701–703.
↑ Reading CM. (1979). “X-linked dominant manic-depressive illness: Linkage with Xg blood-group, red-green color-blindness and vitamin-B12 deficiency”. Orthomolecular Psychiatry. 8: 68–77.
↑ Reading CM. (1975). “Latent pernicious anemia: A preliminary report”. Medical Journal of Australia. 40: 91–4.