This Viral TikTok Trend Might Be Causing Your Hair To Fall Out

<span class="copyright">Getty Images</span>
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A viral hair-cleaning hack may be doing more harm than good.

Hair training is a trick for achieving longer-lasting clean hair that has grown popular on TikTok, with #hairtrainingtips reaching 260.3 million posts and #traininghair reaching 280.2 million posts and counting. Many fans of the technique swear they can go weeks or even months without shampooing — a promise that’s especially tempting for those with oily hair. But does it actually deliver, and is this trend causing more harm than good?

What’s the lowdown on hair training?

Hair training is the practice of gradually extending the time between hair washes to train the scalp to produce less oil, which aims to make your hair look and feel cleaner for longer periods between washes. A major perk, as supporters of the trend claim, is to be able to condition your hair to fit your perfect wash schedule. 

Is hair training the real deal?

According to the pros, the answer is no. “While the concept sounds appealing, the science just doesn’t support it,” said hair transplant surgeon and dermatologist Dr. Hannah Kopelman. “If you’re not washing [your hair] regularly, what you’re really doing is allowing sebum, sweat and impurities to build up on your scalp.” That can lead to more hair falling out or other scalp issues, she noted.

Excessive oil and debris on the scalp can also lead to seborrheic dermatitis, a common skin condition that causes dandruff, inflammation and scaly patches, points out board-certified cosmetic dermatologist Dr. Michele Green. “Scratching it can lead to hair loss due to damaging the hair follicles,” she said.

Sebaceous glands, distributed across the scalp, are responsible for producing sebum, a natural oil that moisturizes and protects the scalp and hair from drying out.

“Sebum is actually a good thing — up to a point,” Kopelman explained. “When there’s an excess of sebum, it can lead to clogged pores, dandruff and even contribute to hair thinning.” Though your genetic makeup plays a significant role in determining how oily or dry your scalp naturally is, there’s a whole mix of other factors at play. Hormonal changes, stress levels, diet and even your environment can cause oil to accumulate faster on the scalp for some than others. “If you live in a humid climate or are going through a stressful period, you might notice your scalp getting oilier faster,” Kopelman explained.

Since sebum production is a natural process largely driven by genetics and hormones, how often you wash your hair doesn’t actually change the amount of sebum produced. “In reality, hair training doesn’t change the function of your sebaceous glands,” Kopelman said.

How often should you wash your hair? 

“When it comes to how often you should wash your hair, there’s no one-size-fits-all answer,” Green said. “It’s all about understanding your unique hair type and scalp condition.”

Generally, those with curly, coarse or dry hair can stretch the time between washes longer than those with thin, fine or oily hair. However, there are telltale signs that it’s time for a wash, like hair that looks greasy and feels heavy or limp, or if you notice dandruff or an odor caused by bacteria or fungus growing on the scalp.

Certified trichologist Shab Caspara also notes that other signs include roots looking piecey instead of soft and flowy. “If your scalp becomes sore after a few days of not washing or even the slightest bit itchy, it’s imperative to wash your hair,” Caspara said.

Here’s how to extend the time between washes.

If you’re looking to extend by a day or two between washes, there are a few tried-and-true methods that Kopelman recommends to get you there.

Scalp gua sha, which uses a flat tool to gently scrape the scalp, promotes lymphatic drainage and helps dislodge sebum and impurities. Dry brushing with a natural bristle brush also works wonders, gently exfoliating the scalp to lift away excess sebum and debris that can clog pores while boosting blood circulation for healthier hair growth. Doing this before you wash your hair helps to loosen up any debris and sebum, making your shampoo much more effective, Kopelman said. “For most people, using these methods one to two times a week is sufficient. It’s important not to overdo it, as too much exfoliation can irritate the scalp,” she added. 

Aside from steering clear of heavy styling products that can weigh down your hair and contribute to quicker sebum buildup post-wash, blow-drying using a lower heat setting and focusing on the roots is also a trick to help keep hair feeling less greasy between washes. “If you let your hair air-dry, the moisture left on your scalp can sometimes signal your sebaceous glands to produce more oil, almost as if your scalp is trying to make up for the natural oils that were washed away,” Kopelman said. “This can lead to that greasy feeling sooner than you’d like.” Though neither of these methods actually decreases sebum production, they help the roots feel less greasy by moving sebum away from the scalp to the strands.

Can I still use dry shampoo? 

Overall, hair and scalp experts advise against relying on dry shampoo as the primary method for managing oily scalps.

“Dry shampoo doesn’t clean the scalp or hair. Rather, it absorbs oil and adds to the products on the hair that need to be washed off,” Green said. While they’re safe to use once in a while to fix greasy hair in a pinch, dry shampoos shouldn’t be used several days in a row, as they can clog hair follicles by adding starchy buildup to the scalp. Instead of aerosol dry shampoos that typically contain irritants like alcohol and isobutane, Green recommends trying powder dry shampoos that are fragrance-free, and contain gentle ingredients such as cornstarch or arrowroot to absorb excess oil from the hair.

While the idea of hair training might sound appealing, it’s clear that experts aren’t on board. Whether you shampoo daily or twice a week, the key is to build a routine that suits your needs to keep your hair looking and feeling fresher for longer without compromising your scalp health.

Looking for a thickening shampoo? HuffPost Shopping Senior Writer Lourdes Uribe rounded up these highly reviewed products.

HuffPost and its publishing partners may receive a commission from some purchases made via links on this page. Every item is independently curated by the HuffPost Shopping team. Prices and availability are subject to change.

Aveda Invati Advanced exfoliating shampoo
Aveda Invati Advanced exfoliating shampoo

Nordstrom

Aveda Invati Advanced exfoliating shampoo

Any time I've had to deal with major hair loss, I've turned to this shampoo with great results. It's the first thing I recommend to anyone experiencing thinning hair, regardless of the cause. It is part of a hair care system that includes a conditioner, foam, mask and a scalp spray, but I find that if you can only afford one, then the shampoo is the way to go. It uses salicylic acid to remove buildup that can clog pores, and the brand includes ingredients like ginseng and turmeric that it says can invigorate the scalp. I was a skeptic at first, but seeing is believing. It really made a huge difference for me.

Promising review: "My mom gifted me the Invati set of shampoo (light) and conditioner for Christmas. We live in rural Canada and have hard well water that has been my hair's nemesis since moving here ten years ago! My hair is no longer dry and brittle...this shampoo is a miracle at keeping those minerals from doing their nasty thing. The last time I went for a hair cut my stylist noticed a ton of new hair growth... so it's working! I'd say it took me a couple of months to really notice a difference on that front. Please keep making this awesome product!" — Kate

$38+ at Nordstrom

Living Proof Full shampoo
Living Proof Full shampoo

Sephora

Living Proof Full shampoo

I've written about my love of Living Proof products before and have no doubt that this thickening shampoo does what it claims. It uses a blend of aminos, peptides and phyantriol that can deep clean the hair without stripping it of moisture or damaging color, all while plumping up the hair fibers and helping prevent damage from heat styling.

Promising review: "This shampoo does not leave my hair oily and helps keep it feeling fuller and strong. I also find I can go longer between washes while using this product. It has become a staple in my routine!" — Rabecky

$34+ at Sephora

Crown Affair The Ritual shampoo
Crown Affair The Ritual shampoo

Sephora

Crown Affair The Ritual shampoo

This is currently my shampoo of choice and I absolutely adore it. It doesn't market itself as a thickening shampoo, but it absolutely leaves my hair thicker and fuller when I use it. Even my mother (who has much thinner hair than mine) was shocked to find how much thicker her hair looked and felt after trying it. It also leaves my hair and scalp cleaner than any other shampoo I've ever tried. It's truly a cut above in every respect and, in my opinion, worth the price. 

Promising review: "The CA shampoo + conditioner have revolutionized my hair. I have long, fine hair that is very prone to tangles with natural shampoos, and the CA products leave mine tangle free and shiny, but without weighing it does with additives. It smells just like a lighter D&G Light Blue—like catching a whiff of lemons on the air in Capri—and I love the ritual of using it. I have to wash/condition daily, and this is the perfect product, as it’s light and natural. Could not recommend more." — Kateinbrooklyn

$36 at Sephora

Alterna Haircare Caviar Anti-Aging Clinical Densifying shampoo
Alterna Haircare Caviar Anti-Aging Clinical Densifying shampoo

Sephora

Alterna Haircare Caviar Anti-Aging Clinical Densifying shampoo

Great for all hair types, this popular Alterna shampoo is a luxurious blend of hair-healthy ingredients like caviar extract, red clover and amia Indian gooseberry. It helps to get rid of the buildup that can weigh hair down, cleansing it thoroughly while making your hair look and feel thicker without irritating the scalp.

Promising review: "My hair was looking and feeling dull and dry. I have some great conditioners but have been having difficulty with finding a shampoo that would make my hair look less dull and dry. This shampoo instantly made my hair feel soft and it looks fantastic! Plenty of volume and looks much healthier than it has in weeks. Definitely recommend!" — damarisp23

$38 at Sephora

R+Co Dallas Biotin thickening shampoo
R+Co Dallas Biotin thickening shampoo

Amazon

R+Co Dallas Biotin thickening shampoo

This popular shampoo uses advanced polymers to create a bouncy, voluminous look while antioxidants like moringa seed extract and golden root extract are included to help protect hair from stress and free radicals and repair damage. It's a great option for people with naturally fine hair who want to give their hair a boost of thickness. 

Promising review: "Hair has never felt better. Although it’s a little on the pricier side of shampoo, R+Co Thickening Shampoo truly lives up to its name. I’ve always had limp, dull, fine hair my entire adult life and after officially using this product for a year I can see and feel the difference in my hair. I’m looking forward to continue using it and seeing how much more my hair will improve over time!" — Allie Wonner

$34 at Amazon

Kérastase Densifique thickening shampoo for thinning hair
Kérastase Densifique thickening shampoo for thinning hair

Sephora

Kérastase Densifique thickening shampoo for thinning hair

Reviewers swear by this shampoo formula. It's made with hyaluronic acid, ceramides and peptides that visibly thicken hair while promoting shine, strength and volume. It gently cleanses the hair without stripping it of natural oils while helping to improve texture and overall thickness over time.

Promising review: "Definitely stuck on this one now! This makes my hair look and feel thicker and it makes it feel soft too. There’s no gross smell or feel when you use it and I think it’s worth the price." — kilianm

$40 at Sephora

Briogeo Destined for Density shampoo for fine and thinning hair
Briogeo Destined for Density shampoo for fine and thinning hair

Dermstore

Briogeo Destined for Density shampoo for fine and thinning hair

Beauty devotees know that the under-the-radar brand Briogeo always delivers results. This density-boosting shampoo is made with copper peptides, zinc, biotin and vitamin E, all of which can help to visibly thicken hair while supporting its overall health.

Promising review: "This is a new find for me and I really like this product! I have fine hair and need a volumizing shampoo and this product delivers! I also love the price point and that it is a clean brand! Will repurchase!" — Leah

$32 at Dermstore

Davines Volu shampoo
Davines Volu shampoo

Amazon

Davines Volu shampoo

I'm a big fan of Davines' hair care line, and this volumizing shampoo is no exception. The gel formula gives hair lovely lift and boost, adding life and volume while also making it feel squeaky clean in a good way. This certified B-Corp brand is great for anyone looking to spend their money on socially and environmentally conscious brands without sacrificing results. 

Promising review: "So I have been buying the wrong hair products for my hair type for my whole life. I have fine thin hair, and wear tape in extensions. I have bought so many shampoos, conditioners. Leave in, shines etc- to get that perfect hair after blow drying. This is the best i have had yet. I bought the shampoo, conditioner, leave in spray and some leave in for blondes. And my hair was not flat, had volume, and felt amazing and has lasted me a few days now. I’m beyond happen. It doesn’t have a strong smell at all, so if your into those products with heavy smells ( like me) this isn’t that- but what is does is the best yet." — Brittany Lachs

$34 at Amazon

Sachajuan thickening shampoo
Sachajuan thickening shampoo

Amazon

Sachajuan thickening shampoo

I've used this shampoo before and definitely found that it left my hair feeling thicker and fuller, without compromising on smoothness. It has heat and UV protectants and the brand's proprietary thickening technology that can help to create volume and bounciness. It's a great under-the-radar option for people with naturally thin hair.

Promising review: "When I ordered this thickening shampoo, I didn’t have high expectations. I’m happy to say I was wrong!! My hair used to look limp, thin and lifeless an hour after blowing it dry. With this shampoo, my hair seriously looks twice as thick. It may seem pricey, but you don’t need to use a lot for good results. Therefore it lasts a long time. I’m definitely a customer for life!" — Cheryl Champion

$31 at Amazon

Ouai Thick Hair shampoo
Ouai Thick Hair shampoo

Sephora

Ouai Thick Hair shampoo

If you're into fragrances, then this thickening shampoo is for you. Tt's scented with notes of rose, Italian lemon, jasmine and white musk. It is color-safe and has a multifunctional formula that tackles frizz, dryness and damage while also adding bounciness, shine and volume. 

Promising review: "I loved QUAI shampoo completely transformed my hair from dull to full! This shampoo will never make you go back to whatever you used before. Definitely a transformer for the better! Love it" —alyssalauni

$32 at Sephora

The Nue Co. Supa Thick shampoo for hair growth
The Nue Co. Supa Thick shampoo for hair growth

Sephora

The Nue Co. Supa Thick shampoo for hair growth

This low-pH shampoo is great for anyone who needs to be extra gentle with their tresses. It's formulated to protect the scalp's microbiome and strengthen the hair cuticle, leaving hair nourished, full and healthy. It can help to reduce breakage and damage, restoring it to its former glory and helping to protect against daily stressors.

Promising review: "Smells great, leaves your hair feeling soft and bountiful, doesn't leave it oily or frizzy. It lathers up nicely and really cleans my hair! I use it every single time I wash my hair and notice my hair getting thicker!" — sugarwithtea

$22 at Sephora

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