Dry Shampoo Challenge: Could You Wash Your Hair Just Once A Month?

Editor’s note (10.2022): After I published this post, new analysis showed that 70% of dry shampoos contain benzene, a potent carcinogen. And this wasn’t just a small amount: Researchers found 340 parts per million in 10 seconds of spray; according to the FDA, the acceptable level of benzene in a drug is two parts per million. The problem is the propellant: Unilever, Procter & Gamble, and Johnson & Johnson have recalled at least 10 aerosol brands over the past 18 months, and these include hair sprays as well as dry shampoos.

Because manufacturers are not required to list all ingredients on labels it may be difficult to determine if your dry shampoo is safe, but here are a few “red flags” to look for: butane, propane, isobutane, and tetrafluoropropene. Although it claims to be “formulated without benzene,” Vegamour’s Grow Dry Shampoo lists isobutane on its label, so I reached out to the company and will update with that information once they respond. Meanwhile, please check with the manufacturer if you use aerosol products, including hair spray or dry shampoo (powder should be fine).

My sister in law has the most amazing hair — threaded with beautiful streaks of pure silver. We both stopped trimming during the pandemic and now we each have hair that reaches nearly to our waists. But while hers is thick all the way to the ends, mine keeps getting thinner. What’s her secret? She washes her hair just once a month!

This is crazy to me, as I’m a person who used to shampoo every day. Recently I realized how harmful excessive shampooing is for my hair and scalp — not to mention the environment. I began following a regimen to help fight the hair loss that naturally comes with aging, which includes less shampooing. (Added bonus: Washing less saves water!)

But THIRTY DAYS? That seems insane. Yet my SIL swears it’s easy: She just uses dry shampoo.

Dry Shampoo 101

Hair powdering tracks back to the 17th century, when Kind Louis Xlll began wearing a wig to mask premature balding. For most of the 20th century, people washed their hair just once monthly and used hair powder in between. 

It was only until companies began marketing directly to consumers — a practice that reached new heights in the 1970s with shampoo ads starring luminaries like Farrah Fawcett and Christie Brinkley — that many Americans adopted a daily hair wash practice. Then Heather Locklear told two friends about Breck and the rest was history.

Powder vs. Spray

Dry shampoo powders typically include mattifiers like rice starch, arrowroot, or clay. For years, I’ve used them to reduce oil between washes.

But in dark hair like mine, the powder residue can show up — once, my husband referred to this as my “George Washington” look. (I was not amused.) And although tinted dry shampoo powder would seem to provide a solution, when I tried those the color just ended up on my scalp.

Yuck. 

Instead, my SIL uses dry shampoo spray. The product is more evenly dispersed throughout the hair and shows less residue.

Are Dry Shampoos Toxic?

Dry shampoo sprays used to be made with chlorofluorocarbons, known as CFCs, which damaged the ozone layer. Now, those have been federally banned and the ozone layer is repairing. Yay!

But there are still potentially toxic ingredients in both spray and powder dry shampoos. Avoid dry shampoo powders made with talc, which can be toxic when inhaled, as well as sprays that use vinyl chloride as a propellant. Read your labels to avoid red-flag ingredients.

Right now, I’m loving the Gro Dry Shampoo from Vegamour. It’s made with USDA Certified Organic rice hulls and other vegan ingredients and has a refreshing, citrus-y scent that wears off quickly and doesn’t leave you smelling like you just walked through the perfume section of a department store. (Full disclosure: Vegamour did not sponsor this post, but they did sponsor a previous Mommy Greenest post.)

How to Dry Shampoo

Whether you use powder or spray dry shampoo, the trick is how you use it:

1. Apply to roots — especially at the crown and around the ears, where oil glands are most active. You can spray or tap powder directly onto the scalp; I’ve also found that tapping powder into my palms and rubbing them through my hair works great.

2. Now flip your hair upside-down and rub your scalp and strands with your fingertips, just like you would do if you were shampooing your hair. 

3. Then brush the product all the way through your hair. You should not see any white spots or sprinkles. If you do, brush again until they’re gone.

When to Dry Shampoo

I follow this practice daily, as dry shampoos also help to give my thin hair body and volume. So far, I can skip shampooing for about four days: The first two days are okay, but by day four it all goes up in a ponytail or bun.

How about you — how many days can you go without shampooing? Please tell me, in comments below. Thanks!