Episode SummaryVitamin B12 seems simple — until you flip the bottle over and see four different names on it: methylcobalamin, cyanocobalamin, hydroxocobalamin, adenosylcobalamin. Are they interchangeable? Not exactly. In this episode, I walk through my patient Ann's story — a woman who did everything right, made real progress on her health, and then developed a strange new symptom the moment we adjusted one supplement. Her story is the perfect example of something I say all the time: every supplement has a job, and sometimes the problem isn't the supplement itself — it's the dose. Along the way, we get into the four forms of B12, where the name "cobalamin" actually comes from (it involves German miners and goblins — I'm not kidding), and why the B12 in your multivitamin probably isn't the same form your body gets from food. What You'll LearnWhy vitamin B12 isn't just one nutrient — it's four different forms, each with its own job in the bodyThe real story behind Ann: how backing down one supplement (not adding anything new) resolved a symptom no one expectedWhat methylation is, and why it matters even if you've never heard the word MTHFRWhy cyanocobalamin — the most common form in multivitamins — actually contains a small cyanide molecule, and why that's not something to panic aboutThe surprisingly fun origin of the word "cobalamin" (hint: it involves 300-year-old mining folklore)How to think about methylcobalamin, adenosylcobalamin, and hydroxocobalamin — what each one actually does, and who tends to benefit from itWhich forms of B12 show up naturally in food, and why that matters more than most supplement labels let onWhy "more" or "more active" isn't automatically better when it comes to methylated nutrients Timestamps[00:00] Cold Open — Meet Ann: 52, exhausted, stuck, and the unexpected symptom that led to a bigger lesson about B12[Segment 1] Every Supplement Has a Job — Why this isn't a story about methylated B vitamins being "bad"[Segment 2] Why Methylation Matters — A plain-language explanation of methylation and where B12 fits in[Segment 3] Where This Understanding Came From — My training background in methylation science[Segment 4] Wait... B12 Has Cyanide In It? — The truth about cyanocobalamin, explained without the fear-mongering[Segment 5] The Goblin Story — Why B12 is red, and the surprisingly fun history behind the name "cobalamin"[Segment 6] The Four Forms of B12 — Cyanocobalamin, methylcobalamin, adenosylcobalamin, and hydroxocobalamin, explained through real patient personas[Segment 7] Which Forms Are Actually Found in Food? — What meat, dairy, and eggs naturally provide — and why cyanocobalamin barely exists in nature[Segment 8] The Bigger Lesson — Back to Ann, and what her story teaches about listening to your body[Closing] — Recap, and an introduction to the free Supplement Audit series