New York City-based board-certified dermatologist Arash Akhavan says that tea tree oil has antibacterial, anti-fungal, and anti-inflammatory benefits to rid your scalp of excess oil, sweat, and product build-up. “It has also been shown to reduce the symptoms of dandruff and other inflammatory conditions of the scalp,” he previously explained.
Fancy and Effective Ingredients: Alterna Caviar Clinical Densifying Shampoo
Stacy Chimento, MD, a board-certified dermatologist at Riverchase Dermatology in Bay Harbor Islands, Florida, recommends this hair density-boosting formula because of its effective, jam-packed formula. It contains strengthening biotin and keratin; antioxidant-rich alma Indian gooseberry oil to fight free radical damage; amino acids like hydrolyzed vegetable and hydrolyzed soy proteins to help thinning hair build new strands; and moisturizers glycerin, sunflower seed oil, and caviar to stave off dryness and keep hair shiny and silky.
As a bonus, you won’t find any synthetic colors and dyes in this formula. “It also removes environmental residues and excess sebum, which allows for thicker-looking hair to rise to the surface,” Dr. Chimento says.
Best for Color-Treated Hair: Olaplex No.4 Bond Maintenance Shampoo
Olaplex’s line of strengthening hair-care essentials has long been an Allure editor favorite but the brand’s Best of Beauty-winning No. 4 Bond Maintenance Shampoo in particular has earned high praise from Annie Gonzalez, MD, a board-certified dermatologist in Miami, for its protective qualities that come from ingredients like Olaplex’s signature bond-building molecule. Dr. Gonzalez adds that this strengthening shampoo really works to protect your locks from breakage and is perfect for color-treated hair. “The less hair breakage, the fuller and thicker your hair will be,” she says.
Best-Smelling Shampoo: Ouai Fine Hair Shampoo
In addition to smelling like absolute heaven (or a blend of rose, Italian lemon, jasmine, and white musk, to be exact), Ouai’s Fine Hair Shampoo comes highly recommended by New York City-based board-certified dermatologist Kavita Mariwalla, MD. “Whether your hair is thinning or you feel like it just looks flat, this makes a difference with chia seed oil that penetrates the hair to give it hydration and bounce, along with biotin and keratin,” she says.
Dry-Scalp Soother: Art Naturals Moroccan Argan Oil Shampoo
Michele Green, MD, a board-certified cosmetic dermatologist based in New York City, says the Art Naturals Moroccan Argan Oil Shampoo‘s star ingredient is rich in fatty acids and vitamin E, two compounds that moisturize and soothe dry scalp and hair. She also notes that argan oil has antimicrobial properties that can support scalp health and reduce itchiness caused by infections like folliculitis. “Argan oil is a good option for those who experience thin, brittle, and dry hair and want to repair damage while protecting against additional damage from heating tools, harsh chemicals, or the sun,” she says.
Best for Dandruff-Prone Hair: Nizoral Shampoo
Yes, this shampoo’s main claim to fame is its ability to reduce dandruff and flaking, but Dr. Green says its ketoconazole-spiked formula is also helpful in promoting hair growth. She notes that a study published in Dermatologic Therapy suggests that ketoconazole may block the action of an enzyme, 5-alpha reductase (5AR), that converts testosterone into dihydrotestosterone (DHT), the latter being a hormone that can cause hair loss in both men and women with age — though more extensive clinical studies are needed to validate these findings. “By blocking 5AR, DHT levels decrease and can help slow down hair loss and support hair growth,” she says.
Best for Greasy Scalps: Kérastase Spécifique Bain Divalent
This Kérastase pick is a favorite of Dr. Mariwalla, specifically for “strengthening hair, especially as we age,” she says. It’s also formulated for people who are dealing with greasy scalps but have brittle, dry hair. The shampoo targets these concerns with vitamin B6, which works to slow sebum production, along with glycine, an amino acid that deeply moisturizes strands.
Allure Editor Favorite: Andrew Fitzsimons Body Volume Boosting Shampoo
A Best of Beauty Award winner, the Body Volume Boosting Shampoo is the work of hairstylist Andrew Fitzsimons, whose clients include the Kardashians, Adele, and J.Lo, just to name a few). For the quite-reasonable $16 price point, you get a lightweight formula packed with caffeine and hydrolyzed rice protein to strengthen hair, improve elasticity, and give your hair an overall “oomph.”