There’s a Trick to Actually Straighten Your Hair Without Heat

© Getty Images
How to straighten hair (even curly hair) at home perfectly with a straightener, flat iron, or naturally without heat to lessen the risk of damaging hair.

Hair trends may come and go, but straight, smooth strands are a classic look that never goes out of style. That said, getting salon-level results at home can be tricky. So we asked Good Housekeeping Institute Beauty Lab experts and top styling pros for their hair straightening secrets.

Here, they explain how to straighten your hair at home perfectly with a straightener or flat iron without damaging it (including curly hair!), plus how to naturally straighten hair without heat:

How to straighten hair with a flat iron

It may seem, well, straightforward, but GH Beauty Lab scientists reveal their key techniques for smooth sailing when it comes to flat ironing your hair.

1. Get smart about straighteners. No research suggests that a flat iron’s materials (like titanium, ceramic, tourmaline, and copper) have different effects on hair, explains GH Beauty Lab Chemist Danusia Wnek. Instead, choose a tool that fits within your budget and hair’s needs.
2. Protect and smooth strands. In general, unless your hair is naturally somewhat straight, it’s best to start with a smooth blow-dry so you have to do less work with the flat iron, which saves both time and potential hair damage. Post-blow dry, apply a small amount of a heat-protective styling product all over hair and be sure it’s fully dry before flat-ironing it (if your hair is prone to frizz, opt for an anti-frizz serum).
3. I.D. your heat level. When it comes to heat tools, “Begin at a lower temperature and raise it as needed,” Wnek advises. Use low heat on fine hair (240ºF to 330ºF); medium heat on medium-textured, healthy strands (330ºF to 370ºF); and high heat on thick, natural hair (390ºF to 445ºF). If you have chemically treated hair, which is more susceptible to damage, go even lower.
4. Work from the top down. For the most uniform finish, clamp the flat iron onto a 1-inch section of hair at the roots and slowly pull the closed iron straight down to the ends. Release and repeat on the rest of hair.

How to straighten curly and natural textured hair

Whether you’re blessed with natural waves, curls, or coils, you can play with smooth styles, too, thanks to these expert tips tailored to your texture.

1. Choose the right tool. When it comes to straightening textured and curly hair, GH Beauty Lab testing has found both ceramic and titanium flat irons, which are commonly used, to be good conductors of heat and effectively smooth even coarse strands. Most importantly, you’ll want to pick a tool with adjustable heat to get hair sleek without damaging it.

2. Set the best temp. Picking the right temperature is key to minimizing damage. Here are the guidelines for natural hair, according to Leigh Hardges, a hairstylist at Maxine Salon in Chicago. Keep in mind these ranges are a bit different than the above temperature settings in order to effectively smooth thick, coarse, or damage-prone strands:

   • Use low heat on fine curls (320ºF to 350ºF)

   • Use medium heat on normal-thickness natural hair (350ºF to 385ºF)

   • Use high heat on coarse hair and curls (390ºF to 425ºF)

   One caveat: “If you have a 4c curl type, never go above 375ºF or 380ºF,” as this texture is especially damage-prone, Hardges advises.

3. Do some prep. Make sure hair is completely dry before flat ironing and always apply a heat protectant product (and let it dry) before beginning, Hardges recommends, which is even more important for fragile natural and curly textured hair.
4. Divide your hair into vertical sections, which will prevent your arms from getting tired too quickly. Work from your roots to ends, pressing firmly as you move down the section to prevent having to go over it multiple times.” Try your best to only do a single pass from the mid-strand down to the ends, as that is the the oldest hair on the head and most prone to heat damage,” Hardges says.

How to straighten hair without heat

Is it possible to fully straighten your hair without heat or a flat iron? Not entirely, unless your hair is fairly straight to begin with, pros say. But you can get a smoother style using rollers. For “the roller trick”, which adds sleekness to hair without heat, use large velcro or plastic rollers, advises Olivia Smalley, hairstylist and Joico Brand Storyteller in Fort Lauderdale, Florida. “The bigger the roller, the smoother your hair will get,” she explains. Here’s how:

1. Set up. Thoroughly towel-dry your hair, then smooth on an air-drying styling cream and comb through hair to evenly distribute and detangle before styling.
2. Section your hair into large two to three inch pieces (you’ll need one roller for each section). “The number of sections you’ll need depends on the thickness of your hair and the size of the rollers, but you’ll probably need at least six rollers, three on each side,” Smalley says. “If your hair is tightly coiled or very thick, you may need eight or more.”
3. Wind a section of hair, starting near the ends, up around a roller moving away from your face, until all strands in the piece are wound in the roller and you’ve reached the roots. Use a bobby pin or pin curl clip to secure the hair in the roller if needed. Repeat on the rest of the sections. “Affix the rollers as tight to the roots as possible for the best straightening effect,” she advises.
4. Allow strands to air dry completely in the rollers, then unwind the each one and brush through hair.