Ever wonder what is inside the nail polish? What makes nail polish and nail hardeners. Dr. Zoe Diana Draelos, a clinical associate professor in the Department of Dermatology at Wake Forest University published the answer: Nail hardeners are used to increase the strength of brittle nails due to excessive contact with solvents, detergents, and water. Originally, nail hardeners were formulated with at least 10 percent solutions of formaldehyde; however, the Food and Drug Administration recalled these products following reports of illnesses and reversible nail damage. Free formaldehyde in concentrations of 1-2 percent is still permitted, but acetates, toluene, nitrocellulose, acrylic, and polyamide resins are now used to structurally reinforce the nail plate. Some products actually contain 1 percent nylon fibers and are known as fibered nail hardeners. Other additives purported to strengthen the nail include hydrolyzed proteins, modified vegetable extracts, glycerin, propylene glycol, and metal salts.
