Try one of these 14 best hair thickening shampoos—tested and reviewed by Cosmo editors, dermatologists, and stylists—for fine, flat, and curly hair types.

If you have thinning hair that's also brittle, bonding treatments like this shampoo can really come in handy: The formula strengthens and repairs hair while adding moisture and nourishment.

Keratin treatment for thin hair before and after: To straighten without losing volume TikTok user @Georgesian has unrulw waves before getting a keratin treatment done on her hair that looks smooth ...

Ahead, the best keratin shampoos for smoothing frizz, repairing damage, and strengthening your hair according to editor testing and stylist recommendations.

If you have thinning hair that's also brittle, bonding treatments like this shampoo can really come in handy: The formula strengthens and repairs hair while adding moisture and nourishment.

A moisturizing shampoo that’s sulfate-free is the best shampoo for keratin-treated hair, Carolyn Aronson, a professional hairstylist and CEO/founder of It’s A 10 Haircare, tells Elite Daily.

If you have keratin treated hair, this guide will help you figure out how to maintain and style your hair. Updated July 26, 2016, 10:43 AM PDT / Source: iVillage Maria Ricapito ...