Why Is My Straight Hair Turning Wavy

Why Is My Straight Hair Turning Wavy

Most people with straight hair want curls while the opposite is true for those with curls or waves. Interestingly, some very lucky people (or unlucky, depending on how you look at it), have hair that changes shape and texture on its own even without the impacts of weather.

If you have children, you probably notice this more easily. They could be born with one color and texture and as they grow, it does a complete 180.

Your own hair may surprise you, much to your extreme delight, or even to your disappointment.

But if you have straight hair and have been pining away to be among the curly-haired or wavy-headed girls, you could be in luck!

Especially if you hate your hair the way it is naturally, there’s good news for you! As your hair texture can change from straight to wavy.

Why Is My Straight Hair Turning Wavy

Scientists can’t say for certain what makes your straight hair turn wavy. But it’s likely a unique combination of genes, hormones, and medication because all three can impact your outward appearance.

The good news for those with wavy or curly hair is that you could wake up one day and find that your hair has gone from straight to curly or vice versa.

This change in texture is often unpredictable, so don’t be too surprised if you go from having stick-straight hair to wild waves overnight!

There isn’t much you can do to stop this change in texture but at least you know it’s possible. Think of it as a gift!

Keep reading and you’ll find out all about how your hair can change completely plus what you can do yourself to encourage the look you want!

Which Factors are Responsible for Your Hair Shape (Wavy/Straight/Curly)?

You might not have to cry over your hair too long. While your genes do predict a lot, there is much more to it than simply being pre-programmed for your hair type. Keep reading and you’ll have a full understanding about what makes your hair the way it is and how you can change it (if you want to!). 


Did you ever do the Punnett square in science class? Genes do have a lot to say about how you look, including your hair. You might get the curly gene from both your parents and thus, have curly hair.

Likewise, they could both give you the straight hair gene. Or, one could give you curly and one could give you straight so you have an interesting mix in between those.

While it’s not completely common, there are people that do undergo hair transformations despite what genes dictate (without going to the salon). Researchers aren’t quite sure why that is, but some of the other factors we’ll discuss below could play into it.

The shape of your hair follicles

You probably already know that each hair type has a different shape. If you analyze curly hair and straight hair under a microscope, you can see the distinction. The shape is determined by the hair follicle’s shape.

Basically, as the hair grows up and out of it, it acts as a bit of a tube. So how that tube is shaped determines if the hair sprouting from it is curly or straight.

Oval-shaped follicles create curly hair while circular ones make for straight hair. Oval tubes are oddly shaped on one side which causes the curl.

If you notice your hair is going from straight to curly, your hair follicles are changing. It’s suspected this kind of change happens from hormones, though other things can coax it along.

Along with asymmetrical follicles which create an uneven distribution of the keratin in your hair, things like humidity could aid in making those curls.

If you remember those old episodes of Friends on reruns, you can’t possibly forget the episode where Monica’s normally straight and perfect hair frizzes to an oblivion on their trip to Barbados.

Perhaps all it will take is for you to move to a more tropical and humid climate to bring out curls in your hair. Florida is notoriously humid in the states though island living might be a great option for a vacation-like hairstyle year-round!

Here’s Why Your Hair Changes From Straight to Wavy

So, we’ve talked about the impact of genetics, but it isn’t always what makes your hair prone to doing what it does. Those hair follicle shapes really matter, as does the level of humidity you surround yourself with.

But one of the biggest factors for a complete shift in the way your hair behaves has everything to do with hormones. Keep reading to learn more about how hormones come into play for how your hair looks!

Hormones are the main reason why your hair is changing texture

There are certain times in your life where your hormones will make a massive shift. The first encounter you’ll have is during puberty.

Perhaps you had pin-straight hair up until your first period, then POW! Off it went into the land of curls and frizz never to return.

Pregnancy is another time when hormones will change your hair. Most women enthuse about how their hair looks while pregnant. In fact, for many, they claim their hair looks the best it ever has.

All those hormones are working overtime to help with the creation of that baby and you get the glory.

Menopause will come much later on and that too promises some fun (ok, not really fun) in hormonal shifts. On top of dreaded night sweats and other things your mom or grandma have warned you about, your hair may change yet again.

Hormonal changes can do weird things to us all from our skin to our hair to our ability to gain or lose weight. On the bright side, if they change your hair for the better, then you’re winning.

Let’s rundown some of these hormones that could be responsible.

Thyroxine and triiodothyronine come from the thyroid. Doctors have made an observation that fluctuations in the thyroid, most notably from hypothyroidism and hyperthyroidism, can change hair texture.

For those with hypothyroidism, the lack of having plentiful hormones causes hair to become dry and brittle. Meanwhile, those with hyperthyroidism wind up with thinner, oilier, and more brittle hair.

Then there are androgens which are the male sex hormones. Just as men have some estrogen, you have some androgens too.

Androgens boost during puberty for both boys and girls though, and the increase leads to body hair (think why you suddenly needed to start grooming down there during swimsuit season).

For men, androgens are also the cause of why that burst of hair suddenly falls out as they age. In women though, when androgens increase, it can change your hair follicle from round to oval which can change the texture from straight to curly.

Insulin is one hormone most people are familiar with, particularly with such high rates of type 2 diabetes. It regulates your blood sugar, but interestingly, there is a huge correlation between insulin resistance and the kind of hair loss known as alopecia.

So, all your hormonal changes in your life from puberty to beyond having a kid or two (or three or more!) can generate hormonal shifts so great in your body that your hair can change too.

While more research is being conducted on this fascinating topic, it’s important to note that hair is always replacing itself. Even if you have long hair, the hair that’s on your head likely isn’t the same hair as what was on your head when you were a kid (unless you’re that lady from the Guinness Book of World Records who never cut her hair perhaps).

That being said, if new follicles grow back in a different shape, then you could have different hair. Hormones are being studied intently now to prove this link because it seems a very plausible theory as to why hair can suddenly change shape.

There’s something else fascinating to know about those hair follicles. When your hormones change, they can change the tone of your muscles too, including on your scalp. So when that happens, the shape of your hair, the follicles, and the direction they grow can change.

What does all this science mean for you? Quite simply, if your hair has radically changed and you didn’t have your stylist perm or straighten it, you might want to have your hormone levels checked at your next doctor’s appointment.

It could be an early sign of something which may or may not be problematic, yet knowing why your hormones are fluctuating could help you prevent any serious problems.

For example, it may clue you in that you’re pregnant or something else. You can ask your hairdresser and maybe go see the doctor too just to be sure there’s nothing alarming going on.

The wavy gene is activated

Let’s go back to those genes, shall we? The gene that marks straight hair is a recessive one but the curly hair gene isn’t fully dominant.

So what could happen here is that you may very well have that curly hair gene, but until it is somehow activated, you won’t see curls or waves.

On the genetic level, as we age, some of our DNA turns on or off, which research seems to be finding for hair. If you look at men, the hair follicle cells become increasingly sensitive toward DHT (dihydrotestosterone) which causes male pattern baldness.

It’s not yet known which gene is responsible for this, but if science catches up, perhaps we can find a way to switch it off (and find ways to turn on genes we want activated too).

An uneven distribution of keratin in your hair

Want to know something really cool? If you look at a curly hair and a straight hair under a microscope, you’re going to see something very unique. Straight hairs are circular in a cross section and symmetrical.

Curly hairs though are uneven thanks to the keratin distribution. This necessary protein is a main component of hair and in curly hair, it accumulates near the inner edge of your curls, beneath the curves.

Fascinatingly, even if you’re born with straight hair, it can turn curly. There is a cellular receptor called EGFR clusters that sit on the outer root sheath of your follicles. They seem to regulate the growth of hair.

It was found when certain cancer drugs were used to inhibit these receptors and patients had the interesting side effect of developing curly hair.

Your hair care regimen

How you have always cared for your hair says a lot about how it looks now. If your hair is still long and has been for years, you’ve likely subjected it to chemicals or heat damage.

Some people even get their perms done at an early age and find they have them permanently thanks to doing it before their puberty hormones kicked in.

It definitely can happen when you get a perm. You may be looking at long-term curls, which could be a good thing if you’re happy with the way they look.

Funny how we always want something else, right?

Perms use both chemicals and heat to break down the protein bonds in your hair follicles and strands. Ammonium thioglycolate is the most common perm chemical which breaks down the sulfur or disulfide bonds in your hair proteins.

Hydrogen peroxide is also used to oxidize them back together in that new and curly fashion. But these chemicals can permanently damage your hair follicle leaving your hair this way.

If you loved having those curls though, you might be thrilled with the result. If you were just jumping on the bandwagon with what was on trend and wish you could go back to your former hair, you might be very disappointed.

What can you do to reverse the sudden change in your hair?

Now that we’ve gone on this scientific discovery of your hair and how it could change from straight to curly (or even vice versa), you might wonder what you can do to get it to go back to the way it was.

Not everyone wants their hair to suddenly curl. The same is true for those who have enjoyed having curls and find they’re suddenly gone. Follow the tips below to help your hair!

Choose the products that suit your hair needs

Your absolute first step with taking care of your hair should be making an appointment to see your hair stylist. You want to make sure you know what’s going on with your hair.

Let your stylist analyze your strands for weakness and give you recommendations on what kinds of products would be beneficial for your situation. Just like skincare, using the right formulas can make all the difference.

Weak, delicate hair requires shampoos, conditioners, and styling products that infuse protein, amino acids, and other strengthening ingredients into the hair to reinforce it and help it thrive.

You should always look for shampoos that nourish and hydrate your hair. Never choose anything that could dry it out.

Also, when using a reinforcing conditioner, you want to do the opposite of what you’ve always done when applying it. You’ve likely been told to moisturize at the tips first, but when hair needs reinforcement, you should start at the roots and work your way down.

Enhance the experience and relax a bit too by taking a hot towel and wrapping it around you head while you have the conditioner in. A shower cap works just as well too.

This will help the conditioner penetrate more deeply into your hair follicles and shafts. Protein masks and deep conditioning treatments are also fantastic for boosting hair with more strength and luster for a revitalized appearance.

Don’t go overboard though! You might think the more you deep condition your hair, the healthier it will be. However, using too much of a product too often and overcompensating for the damages you’ve done will only weigh it down. Hair will look duller and rougher when you do that.

Additionally, stay far away from any styling products that contain alcohol. These can dry out your hair further. Shampooing should also be kept to a minimum. Doing it every other day or even less frequently than that will help a lot, unless you have oily hair.

Limit the use of chemicals

You might like that bleachy blonde look, but eventually, it takes its toll. Even other colors and processing techniques will lead to weakened hair. No matter what you do whether it’s bleaching, coloring, perms, or straightening, you can weaken the hair fibers and it could be permanent.

Chemicals used in these processes make for dry and frizzy hair with loads of split ends. If you put your hair up in a ponytail and you find you’ve got sections of shorter hair, you’ve got chemical cut from over-processing your tresses.

You can balance this out by choosing shampoos and conditioners for damaged hair. Supplement with intensive conditioning treatments once weekly to help bolster hair health.

Styling products for your hair are best with stearyl alcohol, a good, fatty alcohol that strengthens weak hair and softens it too.

Should your hair be severely weakened, try a deep-conditioning protein treatment. Do it once per week and apply it all over your hair after using a hydrating shampoo.

Leave this overnight by tying your hair into a bun with a soft scrunchie. Place a towel on your pillow to keep from smearing it everywhere. In the morning, rinse it away.

And if you must color your hair, perhaps to conceal gray, choose conditioner-rich formulations and always ones that are professional-grade, free of ammonia for your best and healthiest hair results.

Check with your physician as certain medication may be responsible

In addition to seeking out your stylist, you should make an appointment with your doctor. You may have hormonal problems that can be corrected or managed with medications. If you’re already on medications though, you may need an adjustment.

One common medication many women take is birth control. If you use the pill, it messes with your hormones. It might not be listed as a side effect on the pill or any other medication for that matter, but any medicine that you need to take potentially adjusts your hormones which can adjust your hair.

Your hairdresser might even be able to notice you’ve been taking meds simply by checking your hair. These artificial ingredients may help you manage health conditions well, but they can also ruin your hair.

If the only medication you’re taking is your birth control, you’ll need to decide if you want to go off it completely or if you want to try a different one. Lose dose pills tend to have less of an effect on your hair though it’s less protection from getting pregnant.

Even vitamins and chemical treatments can lead to a change in the shape of your hair follicles over time. A visit with your doctor can be very telling and help you decide what to do for your best health. You should never stop taking medications or switch them without a doctor so make that appointment today!


Your hair can most certainly change from straight to wavy or even wavy to straight, all without a stylist. Genes can be dormant until switched on but researchers aren’t completely sure how that happens yet.

Hormones seem to be a major factor in how hair behaves though. Hair changes throughout the big hormonal events in our lives and it can be a good thing or a frizzy, unhappy thing.

Consulting a stylist can certainly help you decide how to treat your hair. Consulting your doctor is wise too, especially if you’re on any type of medication that could explain the change. But regardless of all this, you can also choose to embrace the way your hair is now and learn to style it in chic new ways.

If you choose to go that route, do make sure that your hair is in good health. You may be surprised what choosing the right hair care products for your hair can do to enhance your look, whether your hair is curly, wavy, or straight.

Properly nourished hair will always look its best so take care of yourself inside and out to have hair that looks good no matter what!


My name is Hajer and welcome to my site. This is my little haven, my outlet, where I can express myself, and show you everything I've learned about makeup, skincare, hair tips, and so much more, as well as the different beauty mistakes I've made so that you can avoid them.

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