Why curl hair

Beach waves more your vibe? Stick holding your wand straight up. Drill it into your brain: You should hold an iron on your hair for eight to 10 seconds max. And make sure to hold each curl for a consistent amount of time. Ever put an iron on your hair and hear it start to sizzle? Yeah, not good.

That's what happens when your hair is still slightly damp. By Bella Cacciatore. To try to understand that, the investigators came at the problem in a number of ways—experimenting with flexible rubber tubes of different widths and lengths, modeling what they learned in a computer, and throwing in a dash of theory.

The investigators concluded that the biggest variable curly hair has to reckon with is weight. The longer a hair grows, the more of a burden the bottom of the shaft must carry until the strand as a whole topples over.

Straight hair lays flat after that, becoming what the investigators call a 2-D hook, since it effectively moves in just two dimensions, front to back or side to side. A hair with an innate curliness to it is only beginning its adventure in multi-directional physics.

If your curly hair is relatively short, each strand forms what the researchers call a 3-D local helix—growing up, down, swooping in at angles, doubling back on itself. OK, none of that—save the fancy physics talk—is especially new. But controversy aside, many people have found that even if it isn't perfect, it can be super useful in at least being able to identify your curl pattern or patterns so you know where to start when you're shopping for hair-care products.

It's a lot to think about, so we asked two industry texture pros to break down some of the finer points of the texture typing categories. Follow our easy tip sheet below complete with recommendations for your hair-care collection to help you better I. All products featured on Allure are independently selected by our editors. When you buy something through our retail links, we may earn an affiliate commission.

The flatter or more oval-shaped the follicle, the curlier your hair; the more circular the cross-section, the straighter your hair. Identifying your curl shape and pattern or patterns is best determined while your hair is sopping wet. A simple breakdown: Type 1s are straight, Type 2s are wavy, Type 3s are curly, and Type 4s are coily. The sub-classifications of A to C are based on the width or diameter of your wave, curl, or coil pattern.

Type 2 waves are bendable, can be fine to coarse, and have a definitive S pattern that lays closer to the head. Almost immediately, the team found evidence dispelling the idea that the number of cells creates the curl. Alas, it's not that simple. The story, as is so often the case with science, doesn't end here.

His study looked only at individual cross sections of sheep hair fibers under a microscope. That snapshot of hair could result from curvature, but it could also have some twisting forces, confusing the results, he said. Even if those cross sections were good representations of hair strands as a whole, it doesn't mean the other theory — the one suggesting that cell numbers are the cause — is wrong.