When it comes to B12 supplements which is the best depends on the B12 form. The most easily digestible and absorbable B12 is in the form methylcobalamin and normally taken sublingually under the tongue as a pill or spray. I think Dr. Mercola’s product is a nasal spray? Either way the key is to bypass the stomach and go directly into the blood stream, which prevents the B12 from being degraded or “ruined” along the way. I have not tried Dr. Mercola’s B12, so I cannot comment much on it, but basically you should find a B12 that is in the recommended forms above. Cyanocobalamin, is the most common form on the market, but the least easy for our body to absorb, get enough of, work with, etc.

All the best.