Which Is Better for Your Hair, Blow

Do you blow-dry your hair after you wash it? I do, but almost 70 percent of the participants in our Twitter poll said they don't. This week I’m looking into which is better for you, blow-drying or air-drying. Also in this issue: How to prevent slips this winter, and the five most reliable car brands.

THE BIG STORY:

One of the biggest culture shocks I experienced moving to the States has to do with the hair dryer. Many Americans I know, including my partner, don't use a blow-dryer. Instead, they prefer to air-dry their hair after they wash it.

That, to me, has never been an option. I grew up in a household where you would get yelled at if you walked around with wet hair. My dad's reasoning was that you had to blow-dry your hair immediately after washing it or risk getting a headache. And now whenever I see my partner puttering around the apartment with dripping wet hair, I yell at him as well. It's all come full circle.

We’ve had a long-standing debate over hair drying. For one, will you really get a headache if your hair is wet for a long time? Also, which method is actually better for your hair, i.e., which will cause your hair less damage—blow-drying or air-drying?

This is what doctors told me.

Wet hair has not been proved to be a consistent trigger for migraines, according to research, says Matthew Robbins, MD, the president-elect of the New York State Neurological Society.

However, people who suffer from migraines often have scalp and hair sensitivity called allodynia, and for them, wet hair might be a plausible cause of headaches, Matthew says.

And if you go to sleep with your hair wet, there may be other factors that can contribute to a headache. For example, a cold, wet pillow could cause repeated, brief awakenings that disturb sleep and prompt a migraine.

What about hair damage? There's little evidence that either air-drying or blow-drying is better for your hair. And there are advantages and disadvantages to both, says Elizabeth Bahar Houshmand, MD, a dermatologist and American Academy of Dermatology fellow in Dallas.

If you’re not careful when you blow-dry your hair, the heat damage can cause split ends and breakage. Also, pulling on your hair while drying can cause trauma to the hair follicles, which may lead to hair loss later, says Lauren Ploch, MD, a board-certified dermatologist in private practice in Aiken, S.C.

However, blow-drying without heat is not damaging, says Julia Tzu, MD, a dermatologist and founder of Wall Street Dermatology in New York City.

And while excessive heat from a hair dryer can damage your hair more than not using a dryer at all, blow-drying your hair at the right distance and temperature can actually cause less damage than letting your hair air-dry, Elizabeth says.

That's because when hair comes in contact with water, it swells. The longer the swelling goes on while the hair is wet, Elizabeth says, the more pressure it puts on the proteins keeping your hair intact, which can lead to more damage.

Okay, so what's the best way to dry my hair? If you prefer to air-dry, it's recommended that you let your hair dry completely before you lie down because friction of wet hair against a pillow or other fabric can cause split ends, Lauren says.

And if you want to blow-dry your hair, remove excess water with a towel first, then use your dryer on a medium setting, holding it 6 inches away to minimize heat exposure. Using a heat protectant on your hair can also lessen breakage, Elizabeth says.

It might also be worthwhile to consider using indirect heat, such as sitting under a hooded dryer or using a diffuser, to lessen the damage, says Janiene Luke, MD, an associate professor at the Loma Linda University Department of Dermatology in California.

One thing to keep in mind is that the choice of a drying method should depend on your hair type, texture, hair style, and hair goals. Blow-drying can add style and volume, but if your hair is more processed, blow-drying and using hot tools like curling irons and flat irons can be more damaging compared with letting your hair air-dry.

Bonus link: Can hair-loss cures really help?

THE GOOD STUFF

These are the five most reliable car brands, according to our survey data on over 300,000 vehicles.

HACK OF THE WEEK

Sixty percent of people take vitamins, minerals, and other supplements on a daily basis, according to a 2022 nationally representative Consumer Reports survey.

But do these supplements actually work? Here's a quick breakdown of what are said to be the benefits of some of the most popular supplements out there and what the evidence actually says.

🐟 Fish oil Why it's taken: Some people take fish oil to improve their memory because they believe it can reduce inflammation in the brain and improve cognitive processes.

Does it actually work? Fish oil does contain omega-3 fatty acids, which are anti-inflammatory, and some research has linked higher levels of it with better brain health. However, at least one study has found that taking fish oil supplements did not lead to improved cognition.

🦴 Calcium Why it's taken: Calcium can help strengthen bones, and low levels of it can lead to bone loss and fractures.

Does it actually work? It's true that calcium can help reduce bone loss and the risk of fractures in older adults. But some research suggests that high levels of supplementation may increase the risk of heart disease, so it's safer to get calcium from food such as sardines, leafy greens, and dairy.

You can read more about our investigation into the health claims of other popular supplements here.

You might also be interested in this: 10 supplements you should always avoid.

MUST-READS OF THE WEEK

👣 How to Prevent Slips and Falls This Winter"Take short, flat steps, like a penguin."

💧 How to Get the Most Out of Your Water-Saving Washing MachineAnd how to fix pesky washer problems.

🩸 Best Blood Pressure Monitors for $50 or LessPlus, our take on the best time to take your blood pressure.

READER'S FEEDBACK

Some TikTok users have asked us this question: Should you use vinegar to clean your dishwasher? Rich Handel, CR's dishwasher detergent tester, says no. He advises against it because the vinegar might eat away at the rubber gaskets in the dishwasher.

A Smarter reader recently wrote in: "Your expert must not live in an area with extraordinarily hard water! I’ve been using vinegar to prevent serious mineral deposit ‘spotting’ on glassware for many years and see no deterioration of gaskets, as he cautions."

Here's a little bit of context for our answer. Some dishwasher manufacturers recommend vinegar for cleaning, while others warn against using anything but a specific cleaner, Rich says. Because it really depends on the machine, the best thing to do is to consult your owner's manual. And in the absence of that, we recommend not using vinegar.

"We got a hairy situation here."

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Pang-Chieh Ho

I'm a newsletter writer who likes looking into the different ways we can live smarter. The topics I cover typically explore unanswered questions we have about the products we use every day and bridge the gaps between what owners' manuals advise and what we actually do. In my spare time, I like to take photos, critique movies out loud while I watch (at home!), and take care of my ever-increasing plant "children."