Supplement for moisture

Splitting, peeling nails are calling out for moisture, so drink plenty of water (at least 68 ounces each day) and supplement with healthy fats, especially gamma-linolenic acid (GLA), a well-known nail strengthener, says Ann Louise Gittleman, PhD, CNS, and author of Fat Flush for Life (Da Capo Press, 2010). Take a daily black currant seed oil or borage oil supplement with at least 360 mg GLA to increase skin-cell strength and regulate water loss, moisturizing from the inside out. The B vitamin biotin helps the body better use fatty acids, making nails more flexible and resilient, says Gittleman. Try: Barlean’s Organic Oils Borage Oil, 1,000 mg; Country Life Biotin, 500 mcg

Let nails go nude

Solvent-based nail products—including acetone-based nail polish remover, most nail lacquers, and even nail-strengthening products—can strip away natural nail and cuticle oils, which is why having manicure-free hands for at least a week helps to revive dry, brittle nails, says Karina Restrepo, manicurist and co-owner of Tierra Mia Organic Nail Spa in Philadelphia. When you remove polish, look for acetone-free polish removers with natural oils like vitamin E.

Because hand creams and oils won’t penetrate nail polish, it’s important to moisturize nails during those polish-free times: Apply jojoba or neem oil or cocoa butter nightly for increased nail flexibility and softer cuticles. Also keep nails short, making them less prone to chips and tears, until they regain durability in a few weeks, Restrepo says. If you have severely damaged nails, plan for a month of polish-free fingers. Try: Karma Organic Nail Polish Remover, Badger Creamy Cocoa Every Day Moisturizer, Organix South TheraNeem Nail & Cuticle Pen

Buff and shine away discoloration

To refresh stained nails, a result of dark-colored polish or formaldehyde, Restrepo recommends gently buffing them with a buffing block to remove discoloration. Or make a paste of one part lemon juice to two parts baking soda and apply to nails. Leave on for five to ten minutes; massage into nails before rinsing with warm water. At your next manicure, choose formaldehyde-free polish: In addition to its link to skin irritation and cancer, formaldehyde reacts with your nails’ keratin protein, causing yellow and brittle nails. Try: Honeybee Gardens Four-Sided Nail File/Buffer, No-Miss nail polish