For a long time I thought heat protectant was optional, a nice extra for people with very fragile hair. Split ends after a summer of daily flat-ironing are usually what changes that mind. Hot tools run hot enough to damage the hair's outer layer, and the effect builds up over time, showing up as frizz, breakage and color that fades faster than it should. A heat protectant puts a light film between the hair and the heat, and many now do more, with smoothing, shine or hold built in. The best heat protectant spray is the one light enough that you never skip it. That is why I prefer mists over creams for daily use: they spread evenly, dry quickly and do not weigh fine hair down. A spray also makes it easier to cover every section, which matters more than any formula claim. The first grid is the mists I would use before a blow-dry, from Olaplex, IGK, Bumble and bumble and Moroccanoil. If you want to keep going, Kenra Blow Dry Spray and the Heat Protectants I Reach For is the one I would read next.

Some protectants disappear, and some leave a little texture or hold behind, which is useful if you style on second-day hair. Oribe's Gold Lust Dry Heat Protection Spray and Kristin Ess's Dry Finish spray are made to go on dry hair before a flat iron or curling wand. Hair by Sam McKnight's Modern Hairspray is a flexible styling mist with heat protection built in, and Living Proof's Perfect Hair Day spray is meant for heat styling from blow-dry to finish. Mist in sections from about eight inches away and let it dry fully before the iron touches your hair. If you hear a sizzle, something is still wet. I went deeper on a related idea in CHI Heat Protectant, and the Pizza Oven Idea Behind the Iron.

The last grid rounds out the options. Rahua's Heat Protectant Shield comes from a brand built around Amazonian rahua oil, BondiBoost's thermal spray adds aloe and rosemary, Philip B.'s thermal spray is the quiet classic of the group, and Leonor Greyl, the Paris hair care house, protects while adding volume with Condition Naturelle. What I would skip is cranking your tools to the highest setting just because a spray is in your routine. A protectant reduces damage, it does not erase it, and fine or color-treated hair usually needs far less heat than the dial allows. Start lower, raise it only if the style will not hold, and give your hair a heat-free day when you can.

Heat protectant is the least exciting step in any hair routine and the one that keeps the rest of it possible. Spray it on every time, on damp hair before the dryer and on dry hair before an iron. Pick a mist you like enough to use daily and keep the heat lower than you think. Your ends will last longer between trims, which is a small habit with a real payoff. If you want to keep browsing, I also put together Why I Went Back to Powder and Designer Slides for Women.