Heat styling without the damage

Heat tools can create sleek, bouncy or curly styles in minutes, but heat changes the proteins in hair and can leave it dry, frizzy and prone to breakage. You do not have to give up heat. Using it less often, at lower temperatures and with good technique makes a big difference.

How heat damages hair

Hair is made mostly of a protein called keratin. High heat can weaken that protein and damage the cuticle, the protective outer layer. Wet hair is especially vulnerable: putting a hot flat iron on damp hair can make the water inside the strand boil, a type of damage sometimes called "bubble hair." Damage builds up over time, and once the strand is damaged, only trimming removes it.

Safer temperatures

Most tools let you set the temperature. Use the lowest setting that styles your hair in one or two passes.

Exact numbers vary by tool and hair; many stylists suggest staying well below the maximum setting for most hair. If you smell burning or see steam from dry hair, the tool is too hot or hair is not fully dry.

Heat protectants

Heat protectant sprays, creams and serums form a film on the hair that can reduce moisture loss and friction during styling. They do not make hair heatproof, but they are a sensible, low-cost habit.

• Apply evenly to damp hair before blow-drying, or to dry hair before irons.
• Comb through so every section is covered.
• Let it dry before using a flat iron.

A better blow-dry

1. Remove excess water first by squeezing gently with a microfiber towel or T-shirt. Rough towel rubbing causes frizz.
2. Rough-dry on medium heat until hair is about 70 to 80 percent dry.
3. Use a nozzle and point airflow down the hair shaft for smoothness.
4. Keep the dryer moving and a few inches from the hair.
5. Finish with a cool shot to set the style.

The American Academy of Dermatology suggests letting hair air-dry when possible and using the lowest heat setting when you do blow-dry.

Flat irons and curling tools

• Work in small sections so one pass is enough.
• Do not hold the iron in one spot or clamp repeatedly on the same section.
• Use ceramic or tourmaline plates with even heat if you are buying a new tool.
• Limit flat ironing to as few times a week as you can.
• For curls without heat, try heatless methods: braids, twists, rollers or a robe-belt wrap overnight.

Signs of heat damage

Recovering

Trim damaged ends, reduce heat for a few months, use deep conditioners and gentle detangling, and protect hair at night with a satin bonnet or silk pillowcase.