Vitamins

Vitamins are traded as much on form as on molecule. Vitamin D3 appears as a pharmaceutical grade crystal, as an oil dilution and as a cold water soluble beadlet, each at a stated potency in international units per gram, and the beadlet exists so that a fat soluble vitamin can be dosed into a drink or a wet premix. The same logic applies to Vitamin E, sold as oil, as a powder on a carrier and in water dispersible form.

Two distinctions govern substitution. Natural Vitamin E is the d-alpha tocopherol form recovered from vegetable oil distillate and is more potent per milligramme than the synthetic dl-alpha form, so the two do not swap at equal weight. Vitamin C is stable as a dry crystal but degrades with moisture, heat, light and trace metals, which is why coated and granulated grades exist for tablets and for bakery use.