4. Synthetic B12 (Cyanocobalamin)
The most common B12 supplement is cyanocobalamin—yes, that “cyano” means it contains a little cyanide. While it’s not instantly deadly, it’s not as effective as natural methylcobalamin and can deplete your body’s glutathione, an essential antioxidant. If you smoke or have certain genetic issues with detox pathways, this combo can be extra risky.
For naturally occurring B12, stick to red meat or liver. Only supplement with methylcobalamin if you need a boost.
5. Calcium Carbonate
Look at that heavy supplement bottle—yep, it’s weighed down with calcium carbonate. It’s basically ground-up rock (chalk!), poorly absorbed, and can build up in your arteries or kidneys, increasing your heart attack risk. Plus, taking excess calcium without enough magnesium (should be a 1:1 ratio!) can cause major magnesium deficiency.
You’re better off getting calcium from dairy, yogurt, cheese, certain leafy greens, and fermented products rather than supplements with this rock-hard filler.
