Normal Vitamin B12 Levels May Still Be Too Low for Brain Health

But what if even “normal” levels could be hiding sneaky problems with your thinking or memory? Why Vitamin B12 Is Your Brain’s Best FriendVitamin B12 is a big deal for your brain health. Here’s the big question: What if “normal” B12 levels aren’t enough as you age? Lower B12 levels — even if still “normal” — were linked to:◦Slower brain signals, like a lagging internet connection. Routine blood tests every six to 12 months allow for early intervention to maintain B12 levels.