Brief Answer:
Megaloblastic anemia. Both needed some times

Detailed Answer:
Thank you for asking

i read your question and i understand your concern. When the doctor is suspecting some anemia especially megaloblastic anemias where size of red blood cells increase ( megaloblasts ) > 100 MCV then we advise these folates and vitamin B 12. Former helps in RBCs maturation and later helps in B 12 replenishment likely causing this pernicious megaloblastic anemia.

So use them in combination and keep an eye on your blood count. Usually B 12 comes in animal sources of food and if one is a vegetarian or does not eat much animal food, then there is a chance of getting B 12 deficient.

So trust your doctor and use them both. it won't do any harm. I hope it helps. take good care of yourself and don't forget to close the discussion please.

Regards
Khan

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