Abstract:
Chronic Fatigue Syndrome/Myalgic encephalomyelitis (CFS/ME) is a complex chronic condition, characterized by periods of extreme fatigue, for which an underlying medical condition has previously not been identified.
Many of the symptoms of CFS/ME, are, though, similar to those with vitamin B12 deficiency. In contrast to nutritional vitamin B12 deficiency, the majority of individuals with CFS have been shown to have functional vitamin B12 deficiency as well as functional vitamin B2 deficiency.
This functional B12 deficiency occurred despite elevated serum B12 being found, and hence presents as Paradoxical vitamin B12 deficiency. As such, CFS due to functional B2 deficiency presents as Paradoxical B12 deficiency.
Maintenance of vitamin B12 functional activity is critically dependent upon functional B2 sufficiency, and hence resolution of CFS there must first be resolution of functional B2 deficiency before treatment with vitamin B12 can be effective.
Source: Gregory Russell-Jones.(2022). Functional Vitamin B12 deficiency in Chronic Fatigue Syndrome. Int J Psychiatry 7(3): 153-158. https://www.researchgate.net/publication/362644480_Functional_Vitamin_B12_deficiency_in_Chronic_Fatigue_Syndrome_International_Journal_of_Psychiatry_Corresponding_author (Full text available as PDF file)