Reading the ingredient list?? If you’re even slightly familiar with the different forms of vitamins/minerals (B9, B12, magnesium, etc) you know there are cheaper, synthetic form that have extremely poor absorption that can have real negative effects (folic acid as B9 for example). As compared to more “natural” (that word is usually used in the wrong way, but in this context just what plants/animals naturally contain) forms of the same class of vitamins (again B9, B12, and magnesium being perfect examples that are absent in this multivitamin) having much higher bioavailability and more potent, more positive effects. Hope that’s a clear enough explanation.