The 8 best shampoos for thinning hair, according to experts

In our review of the best shampoos for hair growth, writer Rebecca Strong recommends the Nutrol Root Purifier Scalp Shampoo, repeatedly returning to it over the years.

"It leaves my scalp feeling super clean without completely stripping my hair, has a lovely citrus-meets-herbal scent, and, most importantly, my hair really does start feeling thicker and stronger after using it for at least a month or two straight."

The star ingredient in this shampoo is quinoa protein, "which contains all nine essential amino acids."These amino acids help strengthen the hair shaft to prevent damage and breakage.

L'Oreal Paris' Ever Strong Sulfate-Free Thickening Shampoo clocks in at under $9 per bottle. This drugstore haircare staple features rosemary leaf oil, which is famous for its anti-inflammatory properties. (It's also worth noting that several studies, including this one from 2015, have also found that rosemary oil can help protect against hair loss.)

Tea tree oil is the obvious hero ingredient in Paul Mitchell Tea Tree Scalp Care Anti-Thinning Shampoo. According to Dr. Green, tea tree oil is "antimicrobial and antifungal, which allows it to soothe the scalp and address any itchiness, redness, swelling, or pain." The shampoo is also infused with glycerin and ginseng, the latter of which can help with hair growth. Check out our guide for more of the best dandruff shampoos.

Revitalash's Thickening Shampoo is a favorite of stylist, colorist, and salon owner Paul Labrecque of Paul Labrecque Salon and Skincare Spa in New York City. This volumizing, color-safe shampoo is even spiked with panthenol, which can help hair appear smooth and shiny. One study also found that panthenol may help mitigate the effects of thinning hair.

The PURA D'OR Original Gold Label Anti-Thinning Biotin Shampoo comes highly recommended by Shelly Aguirre, a stylist at Maxine Salon in Chicago. Per the stylist, the shampoo — which she says is "great for thinning hair" — helps promote thickness and combat breakage with its impressive formula, which is enriched with ingredients (including rosemary oil, argan oil, and tea tree oil) "that assist with promoting hair growth."

Pump up the volume with Bumble and Bumble's Thickening Volume Shampoo, which helps lift even the limpest, thinnest, and most delicate strands. It's also spiked with panthenol and vitamin- and fatty acid-rich aloe, which is known for its cleansing and anti-inflammatory properties.

"For damaged finer hair, I recommend the Kerastase Bain Force Architecte Shampoo," explains Aguirre. She continues, telling Insider: "This protein-balanced shampoo will give finer hair the strength it needs to go on and grow." Plus, this uber-hydrating shampoo is even enriched with conditioning ceramides. 

According to Kenji Ishimoto, a stylist at Salon YOSHIKO at Bergdorf Goodman in New York City, Mielle Organics' Rosemary Mint Strengthening Shampoo is especially ideal for curly and coarse trends. Per the pro, the shampoo — which contains biotin "to provide intense moisture" — is formulated to nourish, cleanse, and strengthen weak and brittle hair. Check out our guide to the best shampoos for curly hair for more top-notch recommendations. 

Ingredients: 

When shopping for the best shampoos for thinning hair, Dr. Green recommends picks formulated with ingredients like "minoxidil, biotin, niacin, argan oil, and coconut oil." Per the pro, the former is "an FDA-approved topical medication" that promotes "thicker and stronger hair growth. However, please note that minoxidil is toxic to animals and can lead to death, so only use it with the utmost precaution. 

Toth, meanwhile, recommends looking for shampoos formulated with "ceramides, peptides, hyaluronic acid, and protein [to] help fortify and strengthen your hair." He continues, telling INSIDER, "Natural plant extracts and oils can decrease scalp inflammation and increase scalp circulation, which will stimulate hair growth."

Finally, regarding which ingredients to avoid, Dr. Green advises steering clear of ingredients like parabens, sodium lauryl sulfate, and diethanolamine "since they can damage hair follicles and irritate your scalp." 

Hair type: 

Your specific hair type can dictate what kind of shampoo you should use. For example, explains Dr Green, "Individuals with oily hair may want to look for thinning hair shampoos with clarifying ingredients, such as salicylic acid, to clear the scalp and hair strands of residue." Similarly, those with dry hair "will benefit from a thinning hair shampoo that is packed with moisturizing and hydrating ingredients such as coconut oil or shea butter." 

What causes thinning hair?

"The most prevalent cause of hair loss is androgenetic alopecia, also known as male- and/or female-pattern baldness," says Dr. Greene. Androgenetic alopecia, as its name suggests, derives from your genetic makeup. Then there's alopecia areata, a similar autoimmune response that can be related to genes or stress. Other variables that affect hair loss include: "hormones, nutrient deficiencies, and medical conditions [like menopause, hypothyroidism, and PCOS, to name a few]," says Dr. Greene.

Can hair grow back from thinning?

"If the hair loss or thinning is from a cause other than genetics, such as stress, illness, pregnancy, and nutrient deficiencies, the likelihood of regrowth is high," says Dr. Green. However, if you have always had thin hair, "you can't grow thicker hair because the size of the hair follicle cannot be changed."

How often should you shampoo your hair if it's thinning?

Dr. Green advises on wash routines, stating, "the frequency of shampooing does not affect how much hair is shed because the amount of hair shedding for each day is already determined by the body." However, she does note how important it is to "keep the hair and scalp clean," as "shampooing too infrequently can lead to irritation, redness, inflammation, scaling, and flaking." She tells Business Insider that her rule of thumb is to limit yourself to about 3 washes per week.

When should I see a doctor for thinning hair?

"Some initial signs of thinning hair include excessive shedding after brushing the hair or taking a shower, the appearance of bald patches, or a noticeable change in hair density in the hairline," explains Dr. Green. With that in mind, "It is best to consult with a board-certified dermatologist as soon as you notice any of these changes to identify any underlying causes and determine a treatment plan to correct the thinning." 

Do shampoos for hair thinning really work?

In short, says Dr. Green, yes  — so as long as you select shampoos with the right ingredients such as "minoxidil and argan oil." The dermatologist says these staples "can be very effective for maintaining hair and scalp health."

How do thinning hair shampoos work?

Dr. Green explains: "Thinning hair shampoos with the right ingredients, such as argan oil, rosemary, and tea tree oil, can help maintain hair and scalp health, which can be beneficial in combination with minoxidil and other hair loss treatments." Dr. Green reports that minoxidil is instrumental in "increasing hair follicle size and stimulating the growth phase of the hair."

We consulted experts on their suggestions for the best shampoos for thinning according to a wide range of needs (including stylist recommendations and best-selling hair-care brands) and compiled them here, so you can find the best one to suit your treatment plan.