Confused about B12 testing? 🧬 Most doctors check serum B12, but the problem is—they can’t tell if it’s synthetic cyanocobalamin, methylcobalamin, adenosylcobalamin, or hydroxycobalamin. Labs can’t differentiate! So when they say your B12 is “too high,” it’s not clear which form they’re measuring. ⚠️ Don’t panic—focus on how you feel and use the right form your body needs.