These Are The ‘Damaging’ Shampoo Ingredients To Never Use If You’re Prone To Hair Loss, According To Dermatologists And Hairstylists
March 1, 2025 by Mariam Qayum
When dealing with hair loss, the shampoo you use can play a bigger role than you might think. Some shampoos contain harsh ingredients that can strip the scalp of natural oils, leading to dryness, irritation, and even increased hair shedding. Understanding which ingredients to avoid can help protect your hair and promote healthier growth.
We checked in with celebrity hairstylist and creative education director for Scruples, William Whatley; Dr. Kristina Collins, a board-certified dermatologist; Dr. Ross Kopelman, hair transplant surgeon at Kopelman Hair Restoration; and Valerie Aparovich, biochemist and certified cosmetologist-aesthetician at OnSkin to discover the two worst types of shampoo ingredients you should avoid at all costs because they lead to more shedding and damage. According to them, formaldehyde and high sulfate content shampoos are the ones to watch out for.
1. Formaldehyde
"The first type of shampoo and ingredient that can lead to hair loss and shedding is any shampoo containing formaldehyde," says Whatley.
This ingredient is often found in certain treatments and shampoos. Exposure to formaldehyde can lead to inflammation, allergic reactions, and damage to the hair shaft.
"There are several lawsuits against different brands that use formaldehyde as an ingredient in hair [products]. While it serves as a stabilizing agent, its side effects can be highly irritating to the scalp, causing skin damage and irritation, which may lead to hair loss and shedding," he adds.
"Formaldehyde-releasing ingredients, while intended to preserve shampoo formulas, often irritate sensitive scalps, prompting patients to complain of itching, redness, and increased hair shedding due to chronic inflammation," Dr. Kopelman. Yikes!
2. High sulfate content shampoo
The second ingredient to watch out for is high sulfate content shampoo. Whatley says this "is a cleansing ingredient that’s found in some detergents. A high sulfate ingredient, like sodium lauryl sulfate, can also lead to skin irritation and skin reaction, and that can cause damage that can lead to hair loss and shedding."
Aparovich elaborates further and highlights how this can strip your hair of essential natural oils. "Sulfates are salts of sulfuric acid that create abundant foam when coming into contact with water, performing more efficient yet harsh cleansing," she notes. Aparovich adds that the most common forms in shampoo formulations "are sodium laureth sulfate (SLES), sodium lauryl sulfate (SLS), and ammonium lauryl sulfate (ALS). Sulfates are high in pH and can strip the scalp of beneficial oils, disrupting its hydrolipid barrier, provoking irritation, and compromising hair growth potential." If used regularly, it can "lead to hair strands getting weaker, drier, more fragile, and prone to shedding," she adds.
Dr. Collins says to avoid these "aggressive surfactants that strip away natural oils from the scalp and hair. While they create a rich lather, they can be overly drying."
Better Alternatives
Fortunately, there are various other alternatives that won't cause shedding and strip your hair. "Using a sulfate-free shampoo is a great way to help from losing hair and shedding helps keep the scalp and acid mantle in better shape," Whatley suggests, adding that you can also "use a thermal protectant when drying the hair, such as Scruples Heat Up Styling and Finishing Thermal Spray, which will keep you from damaging the hair with any heat or drying tools."
Aparovich also gives us a helpful tip and advises to look for healthy ingredients that nourish the strands. "It’s also essential that the shampoo is formulated with hair-healthful ingredients like plant-derived extracts and oils, as these can greatly contribute to your locks' well-being and visual appeal. Linden, wheat, and aloe vera extracts are excellent for a moisture boost. Nettle, chamomile, calendula, and birch extracts will help reduce itching and irritation and prevent dandruff. Citrus extracts and essential oils such as grapefruit and lemon will make the hair appear shinier and revitalized," she notes.