Yellow 5 Lake Average Colouring Agent/Pigment No known benefits Yellow 5 Lake description A synthetic colouring agent approved for use in foods, drugs and cosmetics. The lake colours are insoluble in water, so are often used in non-aqueous cosmetics such as lipsticks and powder blush. As with all lake colours used in cosmetics, yellow 5 lake is subject to batch certification before each use in cosmetic products. This certifies purity and safety before the colouring agent is added to the product.