7 Nail Strengtheners For Long, Healthy Nails

OPI Nail Envy Advanced Strength Nail Strengthener ($20)

Formulated with biotin, calcium, and vitamins A, C, and E, OPI also has the "Tri-Flex Technology" that helps to reinforce the health of the nail. We love that it comes in multiple colors, so you don't have to choose between healthy nails and polish. When applied, (the brand recommends two coats and an additional coat daily for a week) the TLC treatment keeps your nails looking fresh and shiny.