I am required to take B12 because of my gastric bypass. It is one of those critical vitamins that I malabsorb. I can tell a HUGE difference if I miss it a couple days in a row. Energy level is different. Same with Iron but I'm also iron deficient without it. I would suggest taking it only if you have proven deficency or find yourself with low energy levels even after your doing everything else you need to do. At your next annual physical with your primary care physician have them test your B12 level along with iron. Also,if you do need to take it consider getting the sublinqual B12. If by some chance you also have to take iron make sure you DO NOT take it with calcium or within 2 - 4 hrs after injesting any form of calcium or it will hinder the absorption.
If you are not taking a multivitamin already you should just focus on taking that consistenly first.
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