On top of frizz, the researchers report that alkaline shampoos rough up the hair’s surface, causing cracks in the fiber and leaving strands more prone to breakage, says study author Maria Fernanda Reis Gavazzoni Dias, MD, PhD, professor of the post-graduation program at the Professor Rubem David Azulay Dermatology Institute at Santa Casa de Misericordia do Rio de Janeiro. Short of busting out those paper PH test strips from chem class, there’s no way to tell a shampoo’s pH unless the product specifically claims to be “low pH” or “pH balancing” (which, thankfully, many do). Luckily, most shampoos have a pH that’s either slightly acidic or neutral, which will make hair shiny and smooth by helping the cuticle scales lie flat, says trichologist David Kingsley, PhD, president of the World Trichology Society. “The ultimate test is to look in the mirror—if your hair looks good after you use a particular shampoo, keep using it,” he says. Not happy with what you’re using? Here are five with pH levels that will help banish bad hair days: Media Platforms Design TeamChi Deep Brilliance Balance Instant Neutralizing Shampoo ($14, drugstore.com) Intelligent Nutrients PureLuxe Shampoo($34, intelligentnutrients.com) Media Platforms Design TeamYes To Carrots Scalp Relief Shampoo ($8, yestocarrots.com) Media Platforms Design TeamHonest Shampoo + Body Wash ($10, honest.com) Media Platforms Design TeamBiolage Colorlast Shampoo ($23, ulta.com) MORE: 5 Easy Makeup Tricks To Look 10 Years Younger
