Metformin can decrease absorption of which vitamins?

Metformin can decrease absorption of which vitamins?

• A. Vitamin A and D
• B. Vitamin C and E
• C. Vitamin B12 and folic acid
• D. Vitamin K and B6

Answer: (C)

Metformin can impair the absorption of certain vitamins, most notably vitamin B12 and folic acid. Vitamin B12 absorption happens in the terminal ileum and requires calcium-dependent uptake aided by intrinsic factor. Long-term metformin use has been linked to reduced B12 absorption, likely by interfering with the calcium-dependent transport process, which can lead to B12 deficiency with potential macrocytic anemia and neuropathy. Folate (folic acid) status can also be affected in some patients, contributing further to a risk of deficiency in this context, though the link is less consistent than with B12. That’s why monitoring B12 levels is commonly recommended for people on prolonged metformin therapy, and supplementation is used if deficiency is found. Other vitamins—such as A, D, C, E, K, or B6—are not typically impacted by metformin, so their absorption isn’t a usual concern with this medication.

Metformin can impair the absorption of certain vitamins, most notably vitamin B12 and folic acid. Vitamin B12 absorption happens in the terminal ileum and requires calcium-dependent uptake aided by intrinsic factor. Long-term metformin use has been linked to reduced B12 absorption, likely by interfering with the calcium-dependent transport process, which can lead to B12 deficiency with potential macrocytic anemia and neuropathy. Folate (folic acid) status can also be affected in some patients, contributing further to a risk of deficiency in this context, though the link is less consistent than with B12. That’s why monitoring B12 levels is commonly recommended for people on prolonged metformin therapy, and supplementation is used if deficiency is found. Other vitamins—such as A, D, C, E, K, or B6—are not typically impacted by metformin, so their absorption isn’t a usual concern with this medication.