Although folic acid absorption by the intestine is catalyzed by the proton-coupled folate transporter (PCFT), which has similar affinity for both folic acid and reduced folates ( Table 2 ) (65, 66), the affinity for folic acid of the reduced folate carrier (RFC), which is ubiquitously expressed in all tissues, is 50- to 150-fold lower than that for 5-methylTHF and other reduced folates (Table 2) (65, 66)
Is it normal for symptoms to initially worsen before improving with B12 therapy
High vitamin B12 levels are generally not harmful in individuals with normal kidney function, as there are no known adverse effects of excess B12 in those with proper renal function
Cognitive symptoms, including memory problems and confusion, may show gradual improvement over three to six months, particularly in older adults
Benzyl alcohol is an aromatic alcohol that works by disrupting the bacterial cell membrane
When vitamin B12 is bound to transcobalamin I, the plasma turnover shows a half-life of about 9-10 days