How to Reduce Frizz: A Whole-Day Routine for Humid, Dry and Hard-Water Homes

In a 2007 lab test, hair coated in mineral oil, the stuff in a bottle of baby oil, took up less water from humid air than hair coated in coconut oil. The plainer bottle came out ahead.

Much of what holds up against frizz is like that. It comes down to seven small changes spread across an ordinary day, most of them free, then a few adjustments depending on whether you live with August in Mobile, June in Tucson, January in Minneapolis or a shower door that keeps growing a white crust. Silk comes in at step six, the one that keeps working while you sleep. If you aren't sure why your hair frizzes in the first place, start with why does my hair frizz so easily.

What is the best routine to reduce frizz?

The best routine cuts down on rubbing, harsh cleaning and heat at each point in the day, in roughly this order.

1. Wash as often as your hair needs, and condition every time

The American Academy of Dermatology says straight hair with an oily scalp may need shampoo every day, while dry, curly or thick hair can wait until it needs it, at least once every two to three weeks. Massage shampoo into your scalp and let it flow through the lengths without rubbing it in. Follow with conditioner each time, on the ends for fine or straight hair and the full length for dry or curly hair. Part of the reason is electrical: strong cleansers leave hair's surface more negatively charged, which adds to frizz and friction, and conditioning ingredients neutralize that charge.

2. Wrap your hair and let the towel do the work

A towel wrapped around your hair absorbs the water without any help from you. Rubbing hair dry is on the AAD's list of habits that damage hair. Plenty of people with curls use an old T-shirt, which costs nothing.

3. Comb from the ends, at the right moment

If your hair is straight, let it dry a bit first. If it's textured or tightly curled, comb it while it's damp, or in the shower with conditioner still in. Either way use a wide-tooth comb and start at the ends. Why does my hair tangle when I sleep? goes through it knot by knot.

4. Put something on it before it dries

Use a leave-in on damp lengths, plus a small amount of oil or silicone serum on the mid-lengths and ends. This slows water down and won't seal it out. In that 2007 study, all three oils tested cut the water hair took up, and the film left on the surface did most of the work. Mineral oil, which stays on top of the strand, beat coconut oil, which partly soaks in. Plenty of water still got through. Dimethicone, the silicone in many serums, also coats the strand against rubbing. Fine hair goes limp under much of this, so start with less than you think.

5. Dry and style with less heat

The AAD suggests air-drying when you can, the lowest heat setting when you can't, and hot tools once a week or less, with less time on each section. A silicone-based heat protectant may help too. Air-drying isn't automatically gentle, though. In a 2011 study of hair tresses washed and dried 30 times, a dryer held about 6 inches (15 cm) away and kept moving caused less overall damage than natural drying, while leaving more cracks in the surface. It's one small study, but low heat and a moving dryer are nothing to feel guilty about.

6. Protect the night

Go to bed with dry hair, gathered loosely, and give it a smooth surface to rest on: a silk pillowcase, a silk bonnet, or both. In its tips for curly hair, the American Academy of Dermatology says satin or silk bonnets or pillowcases may reduce friction and preserve your hairstyle. Why does my hair frizz overnight explains what happens on cotton, and the best pillowcase for frizzy hair compares silk with satin.

7. Trim what's frayed

Frayed ends catch on everything, and no product mends them for good. Stylists commonly suggest a trim every 6 to 12 weeks, sooner if you use a lot of heat or color. We know of no study behind that interval, so let your ends be the judge.

How should I change my frizz routine for my climate?

Match the step you lean on to the air you live in. Hair trades water with the air around it, so the same head can swell in August and crackle with static in January.

Where you are	What's going on	What to lean on
Gulf Coast and Southeast summers	Muggy air day and night (Houston's average August dew point is about 72°F), so hair stays loaded with water and blowouts drop	Step 4: serum or oil on dry lengths. Style only when hair is fully dry
Southwest dry heat	Phoenix's average June dew point is about 39°F. Ends run dry and flyaway	Step 1: conditioner, a leave-in, longer gaps between washes. Treat monsoon weeks like the Gulf
Heated homes in winter	Furnace air runs dry, and hats and collars build static	Conditioner and leave-in. A humidifier set for the EPA's 30% to 50% range. More in winter hair care
AC indoors, steam outdoors	Moving between dry and humid air disturbs a style in both directions	Step 4, and modest hopes for the walk to the car

On the stickiest days, some curly-hair educators also suggest a styler without glycerin, which pulls water from the air. It's trial-and-error advice, and it costs nothing to test.

Is hard water making my hair frizzy?

It may be making your hair feel rougher, though the research is thin and hasn't measured frizz. USGS stream data, old as it is, shows the hardest water in parts of Texas, New Mexico, Kansas, Arizona and southern California, and the softest in parts of New England, the Southeast, the Pacific Northwest and Hawaii.

Two small lab studies disagree on what it does. One, using hair from 15 women, found no difference in hair strength; another, using hair from 70 men and water more than twice as hard, found hair got weaker. If your hair feels coated or straw-like after washing, try a chelating shampoo (look for EDTA on the label) about once or twice a month, with conditioner after. Read the fine print before buying a shower filter: many are built for chlorine and sediment, and don't remove the calcium and magnesium that make water hard.

Which anti-frizz advice can I skip?

Skip the cold rinse and the extra brushing. A cold final rinse is a fine way to wake up, but we can't find good evidence that it closes the cuticle, and water gets into the strand at any temperature. Brushing to spread your scalp's oils along your hair isn't needed either: the AAD says to brush and comb only to style. And no single serum will do the work of the other six steps.

See LS Silk pillowcases for step six →

Most of this list is subtraction: fewer passes with the iron, less scrubbing with the towel. What it adds is a few drops of something slick on your ends, and the plain bottle will do.

Frequently asked questions

How often should I wash frizzy hair?

It depends on your scalp and curl pattern more than the frizz. Oily, straight hair may need shampoo daily, while dry or curly hair can often go much longer, as long as the scalp stays comfortable. If your hair feels squeaky or rough after every wash, try washing less often or using a milder shampoo.

What's the quickest way to calm frizz before I leave the house?

Warm a drop or two of serum or light oil between your palms and smooth it over the top layer and ends without brushing. Brushing dry hair, curls especially, tends to add frizz. It won't last all day in muggy air, but it can buy you a few hours.

Should I air-dry or blow-dry frizzy hair?

Air-dry when you have the time and it behaves, which is the AAD's first suggestion. If you blow-dry, use low heat, keep the dryer moving and hold it about 6 inches (15 cm) away. A diffuser attachment disturbs curls less than a bare nozzle.

Does coconut oil help with frizz?

It can slow how fast hair takes up water from the air, at least in lab tests, though mineral oil did more in the one study we rely on. Use very little, mostly on the ends. A lot of oil weighs fine hair down and can make it look greasy before it does anything for frizz.

Does a humidifier help with frizz in winter?

It may help with static, because hair holds a charge more easily when the air is very dry. We know of no study on humidifiers and frizz, so treat it as a sensible try. Aim for 30% to 50% humidity and keep the unit clean, since damp machines can grow mold.

Do I need a water softener to reduce frizz?

Probably not as a first step. Work through conditioning, gentler handling and a chelating shampoo first, since they cost far less and the evidence linking hard water to frizz is thin. A softener is a whole-house decision with reasons of its own.

Related reading: How to Protect Your Hair While You Sleep · Summer Hair Care Tips · Is It Bad to Sleep With Wet Hair?