Evaluation of oxidant and antioxidant status in patients with vitamin B12 deficiency

The aim of this study was to examine the theory that oxidative stress might have an important mediating effect on the deleterious results of vitamin B12 metabolism deficiency seen throughout the body.

Forty patients with vitamin B12 deficiency and 40 healthy controls were included in the study. Venous blood samples were collected from all participants to evaluate serum vitamin B12, homocysteine, methylmalonic acid, total antioxidant status (TAS), and total oxidant status (TOS) levels in the pre- and posttreatment periods.

There were no significant differences in TAS, TOS, or oxidative stress index (OSI) levels between the pretreatment patient and control groups, and there were no significant differences in TAS or TOS levels between the posttreatment and control groups. In addition, there were no significant differences between the pre- and posttreatment TAS, TOS, and OSI levels of the patients.

These findings are remarkable in that cyanocobalamin treatment had no direct effect on oxidant and antioxidant status in patients with vitamin B12 deficiency. The fact that there were no differences in oxidant and antioxidant status between the patients and the controls might suggest that oxidative stress does not play a role in the systemic negative effects of vitamin B12 deficiency.