Just as certain steps in our grooming process seem like a chore—side-eyeing you, body lotion—there are some aspects of adhering to responsible hair care that feel unnecessary. Applying heat protectant has admittedly been one of these. Not to say that as diligent beauty editors we would ever skip it! But, an in-depth look is indeed needed to better understand how they work.
They’re commonly packaged as sprays, creams, blow-dry lotions, prepping formulas, foams and leave-in conditioners, all made to protect strands before heat styling from a blowdryer or iron, as well as even provide some grip and control. What these all have in common are two silicones: cyclomethicone and dimethicone.
What Goes Into a Heat Protectant?
Silicones and Heat Styling
Cyclomethicone is a clear, fast-evaporating, very lightweight silicone commonly used in leave-in hair products. It helps give hair that silky feeling—if your hair has that lovely “slip” after conditioning, that’s cyclomethicone at work.
Dimethicone, the most common kind of silicone, is mainly for use in conditioners and leave-in detanglers because of its shine-imparting and smoothing properties. It has a heavier feel than cyclomethicone and may be a bit harder to rinse off, but it’s what coats and unknots strands and gives them that glide.
Are Heat Protectants Safe?
Worry not and forget what you heard: Both are safe ingredients commonly used in hair products, and the fact that they’re basically ubiquitous attests to how effective they really are in upgrading our hair care experience.
A heat protectant uses silicone compounds to coat the hair with a water-resistant and heat-protective layer. This coating reduces the porosity of the hair strand (the property responsible for making hair strands super susceptible to humidity and changes in weather).
Second, it also helps minimize damage—if you’ve ever colored, straightened or processed hair in any way, or even exposed it to the usual summertime culprits like chlorine, too much UV or saltwater, your strands are particularly vulnerable to added heat.
Finally—and arguably any beauty girl’s favorite bit—they give your locks that famous smoothness that’s only all-too-important in the styling process. Silicones lubricate the shaft and detangle the gnarly knots in your hair, while at the same time sealing the cuticle in to add some shine in the process as well. What’s not to love?
Tips When Using Heat Protectants
1. Know the Different Types
There are several forms of thermal protectants out on the market, each with its own suggested use. Those with fine, limp hair swear by a light-misting spray, such as TIGI Copyright Custom Create Heat Protection Spray, which leaves hair protected from dryness and breakage. Similar conditioning sprays, such as TRESemmé Thermal Creations Instant Heat Tamer Spray, also protect while shielding from heat damage associated with dryers and irons.
Those with coarse, thick or curly hair might need a bit more help in the form of a heavier cream or a leave-in conditioner (we love the added frizz-fighting benefits of Suave Professionals Keratin Infusion Heat Defense Leave-In Conditioner). It’s really all relative at this point. It’s similar to how one might prefer a sheer body moisturizer over a mega-emollient body butter to tackle those ashy elbows.
2. Apply When Wet
Thermal protectants are best applied to wet hair after shampooing and conditioning. This way, they’re spread more easily for even protection, effectively bonding into the shaft and readying it for heat exposure.
3. Understand What They Do
As we’ve all been told, hair is at its most vulnerable when it’s wet. During this time, the physical structure is different, as ionic and hydrogen bonds in the protein hair structure (that provide additional strength to the hair core) are weaker or non-existent. This makes it prone to breakage from combing/tangling and may cause friction. Thermal protectants cushion your hair, making heat more manageable.
And most important: You need to blow-dry your hair before using high-heat irons. Not doing so can result in bubbles, as water inside the hair evaporates rapidly, resulting in severe damage and breakage.
Quick and Easy Application Tips
A few things to remember when applying heat protectants:
Aim for spritzing from a distance of 10 to 12 inches from the head. This diffuses the mist, making for a wider and more even distribution. (Ed’s tip: Try forming the capital letter L with your arm.)
Creams and mousse should be used sparingly—a dime-sized portion is usually enough. Be sure to spread your heat protectant evenly throughout your strands.
And if you’re dealing with hair oils? Hair care products, such as hair oils and serums, are based on silicones rather than real oils. You can always help prevent your hair from cooking on your flat iron by using the bare minimum amount of product for your hair length. You should also opt for ceramic barrettes or plates—they distribute heat more evenly and are generally regarded as safer on strands.
Thermal protectant is the last frontier our strands have against potentially damaging heat exposure. Make it a priority whenever you use heat styling.