Shoppers and InStyle editors swear by the Nioxin System 1 Shampoo for noticeably thicker, longer hair. Snag the expert-backed hair care product for under $30 at Amazon.

It makes hair “thicker, shinier, and smoother,” per shoppers.

Let’s face it: summer can do a number on our hair. Between chlorine damage and UV exposure, it’s easy for our strands to feel dull and dried out this season. That’s why I’m being extra diligent about my mane maintenance, and stocking up on nourishing hair care products. The first item on my list? The Alyssa Milano-used ​​Nioxin System 1 Shampoo, which is under $30 at Amazon.   

The cleansing formula combats light thinning, resulting in fuller, thicker locks. It’s made with hair care heroes, including peppermint oil to support growth and soothe irritation, plus salicylic acid to strip away dead skin and product buildup, and promote a healthier scalp and strands. The shampoo is safe for daily use and recommended to incorporate into your regimen at least three times per week for noticeable results, per the brand.     

Nioxin System 1 Shampoo

$26 at Amazon

InStyle put the Nioxin System 1 Shampoo to the test and deemed it the best derm-backed option on the market. Seasoned beauty editors found that their “dry, thin locks” were “visibly thicker, fuller, and longer after just a month of regular use.” Plus, their “sparse patches” appeared more filled in, and they noticed “additional length thanks to less breakage.” 

Amazon Shoppers With “Limp” Strands Saw Baby Hairs Sprouting With This $19 Growth Oil

We’re not the only fans of the strengthening shampoo, according to its rave reviews. One shopper with thinning hair has gone through two bottles of the formula, and they’ve experienced “so much regrowth.” Another customer confirmed that their hair is “definitely thicker, shinier, and smoother,” adding that they even “stopped using conditioner because it works so well.” And, someone else who’s used the shampoo for just a couple months said their mane is “growing noticeably faster and getting thicker.”    

For your best hair yet, head to Amazon to snag the Nioxin System 1 Shampoo, and browse through more growth products below. 

Mielle Organics Rosemary Mint Scalp Oil

$10 at Amazon

Kate Blanc Cosmetics Castor Oil

Orig. $15 $10 at Amazon

Marc Anthony Grow Long Leave-In Conditioner

$8 at Amazon