1930年代,美国内科医生卡斯尔(W.B. Castle)发现在正常人胃部可分离出一种“内因子”,但却无法在恶性贫血病患的胃分泌物中发现,而这类恶性贫血的患者食用动物的肝脏之后,能改善病情,卡斯尔医生便假设能预防恶性贫血的“外因子”存在于动物的肝脏当中。1934年,乔治·惠普尔、乔治·迈诺特、威廉·莫菲因为“发现贫血的肝脏治疗法”("for their discoveries concerning liver therapy in cases of anaemia")获得诺贝尔生理学或医学奖。1948年-1949年,两位化学家在美国分离出这个抗贫血的因子,并确定此因子为维生素B12。现时,我们知道人体靠胃的上半部来吸收维生素B12。
Yamada, K.; Yamada, Y.; Fukuda, M.; Yamada, S. Bioavailability of dried asakusanori (porphyra tenera) as a source of Cobalamin (Vitamin B12). International journal for vitamin and nutrition research. Internationale Zeitschrift fur Vitamin- und Ernahrungsforschung. Journal international de vitaminologie et de nutrition. 1999, 69 (6): 412–418. PMID 10642899. doi:10.1024/0300-9831.69.6.412.
Almeida, O. P., Ford, A. H., Hirani, V., Singh, V., McCaul, K., & Flicker, L. (2014). B vitamins to enhance treatment response to antidepressants in middle-aged and older adults: results from the B-VITAGE randomised, double-blind, placebo-controlled trial. The British Journal of Psychiatry, 205(6), 450-457.
Biemans, E., Hart, H. E., Rutten, G. E., Renteria, V. G. C., Kooijman-Buiting, A. M., & Beulens, J. W. (2014). Cobalamin status and its relation with depression, cognition and neuropathy in patients with type 2 diabetes mellitus using metformin. Acta diabetologica, 1-11.
Bottiglieri, T., Laundy, M., Crellin, R., Toone, B. K., Carney, M. W., & Reynolds, E. H. (2000). Homocysteine, folate, methylation, and monoamine metabolism in depression. Journal of Neurology, Neurosurgery & Psychiatry, 69(2), 228-232.
Nanri, A., Eguchi, M., Kuwahara, K., Kochi, T., Kurotani, K., Ito, R., ... & Kabe, I. (2014). Macronutrient intake and depressive symptoms among Japanese male workers: The Furukawa Nutrition and Health Study. Psychiatry research, 220(1), 263-268.
Oh, R., & Brown, D. L. (2003). Vitamin B12 deficiency. American family physician, 67(5), 979.