Your hair is curly when it's wet because water pulls your strands together into clumps, and a clump holds a stronger wave than a single strand can. As your hair dries, those clumps come apart, and the weight of the water pulls the wave straighter on its way out. So if your hair is wavy or curly when it's wet but straight when it's dry, you likely have a natural wave that isn't making it from wet to dry.
The good news is that how your hair dries is something you can change. In this article, we'll explain what water does to your hair, why your wave disappears as it dries, and the drying routine that keeps it. If you'd rather keep your hair straight, we cover that too.
Why Is My Hair Curly When Wet?
Your hair looks curlier when it's wet for three main reasons: (1) wet strands stick together into clumps, (2) water changes the weak bonds that hold your hair's shape, and (3) the weight of the water pulls on your hair as it dries. We'll cover all three in this section. Let's get right into them!
the same section of hair, dried two ways
1. Wet Strands Stick Together
When your hair is soaking wet, the water between your strands pulls them together into clumps (Bico et al., 2004). A clump of strands stuck together bends less easily than one strand on its own, so it holds a wave you can see from across the room.
As your hair dries, the water holding each clump together leaves. Unless something else holds those strands in place, the clump splits into single strands, and each one carries a much softer wave. Lots of single strands with a soft wave look straight or frizzy from a few feet away.
Free 8-page guide
You know your hair type. Here’s what it needs on wash day.
Our free guide gives you one page for each hair type group, from 2A to 4C. Each page tells you how often to start washing, what helps your waves, curls, or coils clump, and the problems your hair type runs into most. It also has a protein or moisture chart and a log for testing one change at a time.
Free. You’ll get the guide by email, two more emails on how to use it, and then one every Thursday, plus the occasional extra. Unsubscribe anytime.
2. Water Changes the Bonds in Your Hair
Your hair's shape is held in place by two kinds of bonds. The strong ones, called disulfide bonds, only change with chemicals like relaxers and perms, or with very high heat. The weak ones, called hydrogen bonds, break every time your hair gets wet (Gavazzoni Dias, 2015).
Those hydrogen bonds form again as your hair dries, and they lock in whatever shape your hair is in at that moment. That's how a blow-dry straightens hair, and it's why the way you dry your hair changes how wavy it ends up.
3. Water Weighs Your Hair Down
Wet hair is heavier than dry hair, and each strand hangs from your roots while it dries. On wavy hair, that weight pulls the top of each strand straighter, so the wave hangs on mostly near your ends. A 2014 physics study that modeled a single strand of curly hair with curved rods found the same pattern: the longer the rod, the more its curl collected near the free end, while the top was pulled straighter (Miller et al., 2014).
Keep in mind that straighter textures aren't the only hair types that can develop a different curl pattern when it gets soaking wet. Although it's exceptionally kinky and coily, 4C hair has a tight coil or zigzag that can be hard to see while it's dry.
When it gets wet, however, you probably notice springy ringlets appearing.
Here's why: when 4C hair gets wet, the weight of the water pulls down on and elongates your naturally tight coils. Once the water evaporates, your strands retract and seemingly disappear. That's called shrinkage, and it's the reverse of what happens to wavy hair. Our guide to why 4C hair shrinks explains it in more detail.
Why Curls Go Away When Dry
We've spoken about some potential reasons why your hair curls when it's wet, but you might be facing another problem where your curls only appear when wet.
If you notice that your ringlets go away when your hair dries, here are some reasons why that might be the case.
- You're using the wrong products - Everyone's hair is different, so finding products that work best with your hair takes a lot of trial and error. Try a variety of curl-defining creams, sprays, gels, and mousses to discover the best ones for your hair. When testing out products, be sure you apply them to soaking wet hair. Soaking wet hair is already clumped, so the product spreads evenly and holds those clumps in place as they dry. A hold product, like a mousse or a gel, matters most here. A cream may soften your hair without holding the wave.
- Your natural curl pattern - As we mentioned before, water can change your hair texture and make it appear curlier than it really is. Once the water evaporates, your hair returns to its natural state.
- You're manipulating your hair while it dries - Combing, brushing, blow-drying, or otherwise manipulating your hair while it dries might cause your curls to loosen or disappear. To preserve your natural curls, try to leave your hair alone as it dries. When you do touch it, try to use curl-enhancing techniques like scrunching, plopping with a microfiber towel, and diffusing.
- There's too much water weight - Long or thick hair holds a lot of water, and it can take hours to air dry. The whole time, the weight pulls your roots straight. Plopping your hair takes that weight off while it dries.
- Your products are too heavy - Rich creams, butters, and too much leave-in weigh fine waves down, especially at the roots. Our guide to limp curls covers the other things that flatten waves.
- Part of your hair is damaged - If one section stays straight even when it's soaking wet, with no product in it, heat may have damaged it. That hair won't hold a wave again, so it has to grow out or be trimmed off. We explain how to check in our guide to wet frizz.
What to Do When Your Hair Is Wavy When Wet but Dries Straight
Since your hair keeps the shape it dries in, the goal is to hold your clumps together from the moment you step out of the shower until your hair is completely dry. Here's the drying routine we recommend.
- Squeeze, don't rub. Use a microfiber towel or an old T-shirt to squeeze out just enough water to stop the dripping. Rubbing breaks your clumps apart.
- Style your hair while it's still soaking wet. Put on your mousse or gel right away, while your clumps are still holding together. Smooth it on with flat palms, then scrunch upward.
- Take the weight off. Plop your hair in a T-shirt for a short while, or clip your roots up along your part, so your hair isn't hanging straight down while it dries.
- Don't touch it while it dries. Every touch splits a clump before it sets. Air dry, or use a diffuser on low heat and low speed.
- Scrunch out the crunch. Once your hair is completely dry, scrunch upward to soften the gel cast. The wave stays because the bonds have already set.
Give it two or three wash days before you judge it. The first time you style your hair soaking wet and leave it alone, you'll usually see more wave than you expected, and it gets more predictable from there. Our full wavy hair routine walks through every step of wash day, including how to adjust it for 2A, 2B, and 2C hair.
If You Want Your Hair to Stay Straight
For the most part, your genetics determine your natural curl pattern. If your hair curls when it's wet, there's no product that stops it from curling. What you can change is how long your hair stays straight once you straighten it.
- Blow-dry and flat-iron your hair straight. Use a heat protectant and the lowest heat setting that still straightens your hair. Your hair will stay straight until it gets wet or the air turns humid, because water breaks the bonds that the heat set.
- Smoothing shampoos and conditioners coat your hair to cut frizz, so your hair may lie a little smoother. They won't stop a curl your hair grows naturally.
- Chemical straightening treatments last for months, but they come with real risks. Many keratin smoothing treatments release formaldehyde gas when they're heated, which can irritate your eyes, nose, and throat, and formaldehyde is classified as a human carcinogen (FDA). Relaxers and Japanese straightening permanently break the strong bonds in your hair. Have any of these done by a licensed professional, and don't stack them with other chemical services like color.
For tips on keeping straightened hair from reverting on humid days, see our guide to keeping natural hair straight in humidity.
Frequently Asked Questions
Does Everyone's Hair Get Curly When Wet?
No. Straight hair usually stays straight when it's wet, though it can fall into soft, flat pieces. If your hair shows a clear wave or curl when it's wet, you most likely have some natural wave, even if it dries straight.
Why Is My Daughter's Hair Curly When Wet but Straight When Dry?
For the same reasons as yours. Her wet strands clump together and hold a wave, then separate and get pulled straighter by the water's weight as they dry. Children's hair texture also often changes as they grow, so the pattern you see now may not be the one she has later.
Why Is My Hair Curly When Wet but Frizzy When Dry?
Frizz on dry hair usually means your clumps came apart and the strands dried separately. That happens when something touches your hair while it dries or there isn't enough hold in your styling product. Put mousse or gel on while your hair is soaking wet, and keep your hands off until it's completely dry.
Related Articles
- Hair Webbing Treatment
- Is It Bad to Wet Your Hair Every Day
- Why Is Some of My Hair Curly and Some Straight
- Why Does My Hair Take So Long to Dry Naturally
Playing around with styles is fun, but the more you work with your natural texture, the easier styling your hair will be.
We hope this article has helped you figure out why your hair is curly when it gets wet, and how to keep your waves once it dries, or keep it straight if you'd rather. We wish you the best with your hair!
