Black iron oxide

Black iron oxide (Fe₃O₄) is a mineral pigment of natural or synthetic origin, used since antiquity for its colouring properties. It belongs to the iron oxide family, alongside yellow and red variants, and is recognised as a food additive under the code E172 by European regulatory authorities. Its role in food supplements is exclusively technological: it gives capsules, tablets and coatings their characteristic black or grey hue. It has no nutritional or pharmacological activity of its own, and its use is strictly governed by current regulations, which set maximum usage levels to ensure consumer safety. The benefit of incorporating black iron oxide into a formulation lies primarily in the visual differentiation of products and ease of identification for the user. Its stability to light and heat makes it a reliable colorant for maintaining a uniform appearance throughout the shelf life of the food supplement.