Shoppers Say Their Hair Grew Noticeably Longer After Using This $8 Biotin Shampoo

The struggle to maintain healthy locks without sacrificing hard-earned length to regular trims is real, especially for those whose hair takes ages to grow centimeters. While hundreds of products promise quick results for longer hair, too many fall short of their vows. However, when it comes to growth serums that deliver on their claims to promote thickness and growth, a few have earned a loyal following of users, like the Marc Anthony Grow Long Biotin Shampoo (Buy It, $8, amazon.com).

Already a beloved brand of celebs like Gwyneth Paltrow, Marc Anthony makes hair products centered on hard working ingredients that improve hair health — and the Grow Long Shampoo is no exception. The sulfate- and paraben-free formula contains keratin-promoting biotin, which repairs damage and stimulates growth, as well as ginseng, which has been found to strengthen root follicles. A blend of caffeine and vitamin E further support scalp health by reducing free radical damage and blocking the effects of hormones that cause hair loss. Best of all, customers who used this shampoo for a couple of months noticed a reduction in frizz and fewer split ends, along with an increase in hair growth. (Pssst, here are the best growth serums to add to your routine.)

Buy It: Marc Anthony Grow Long Biotin Shampoo, $8, amazon.com

While you shouldn't expect hair to grow overnight, one shopper measured 3 inches of growth after four months of using the shampoo. Another reviewer used the shampoo for a year and added the length of "three fingers" to their locks without creating split ends. Plus, the shampoo actually leaves hair "super soft" and "shiny," according to a third shopper who noticed their curls making a comeback. An added bonus? Customers say it also smells great. (Want more shopper-loved recs? This shampoo and conditioner set make "a huge difference" in weeks.)

At just $8, this shampoo is as affordable as it is effective, and shoppers recommend adding the brand's Grow Long conditioner or leave-in conditioner for even better results. If you're sick of patiently waiting for your hair to get longer, it's worth giving this shampoo a try. Shop it on Amazon, and in a few months, those centimeters of growth might transform into inches.