Previous: Scientists Let Bees Land in their Eyes
Next: This Animal Lays Eggs AND Has Live Young



View count:1,464
Last sync:2024-06-27 17:15


Citation formatting is not guaranteed to be accurate.
MLA Full: "7 Ways Humans Change Color." YouTube, uploaded by SciShow, 27 June 2024,
MLA Inline: (SciShow, 2024)
APA Full: SciShow. (2024, June 27). 7 Ways Humans Change Color [Video]. YouTube.
APA Inline: (SciShow, 2024)
Chicago Full: SciShow, "7 Ways Humans Change Color.", June 27, 2024, YouTube, 11:54,
Remove your personal information from the web at"> and use code SCISHOW for 20% off. DeleteMe international Plans:">

We're all used to our bodies being more or less the color they always are. But there are a few different medical reason you may be seeing rainbow in the mirror, from benign to medically concerning. Here's just some of the reasons that you might see yourself turn Technicolor!

Hosted by: Stefan Chin (he/him)


Support us for $8/month on Patreon and keep SciShow going!">

Or support us directly:">

Join our SciShow email list to get the latest news and highlights:">


Huge thanks go to the following Patreon supporters for helping us keep SciShow free for everyone forever: DrakoEsper , Friso, Garrett Galloway, Kenny Wilson, J. Copen, Lyndsay Brown, Jeremy Mattern, Jaap Westera, Rizwan Kassim, Christoph Schwanke, Jeffrey Mckishen, Harrison Mills, Eric Jensen, Matt Curls, Chris Mackey, Adam Brainard, Ash, Sam Lutfi, You too can be a nice person, Piya Shedden, charles george, Alex Hackman, Kevin Knupp, Chris Peters, Kevin Bealer, Jason A Saslow


Looking for SciShow elsewhere on the internet?

SciShow Tangents Podcast:">





#SciShow #science #education #learning #complexly


You’re probably used to knowing  exactly what you’re going to see when you look in the mirror.

For example, I’ve got these luscious brown locks, brown eyes, and, I guess… mostly white teeth. Because, from day to day, we  pretty much stay the same color.

Sure, your cheeks might turn pink  when you run into your crush. Or your skin might get a shade  darker after a day at the beach. But we’re not chameleons.

You’re not going to wake up and find  yourself tinted purple or green… But what if you do? Some people, or at least parts of people, have been known to turn  every color of the rainbow. And sometimes it’s a sign that something’s wrong… but other times it’s just some harmless  chemistry going on in your body.

So we’re going to look at  the ways your body could turn all the colors of the rainbow…  and what it means if it does. [♪ INTRO] The first one on our list is something you  may have heard before, which is that eating too many beets can temporarily  color your pee or poo bright red. It’s called beeturia, and it happens when  the red pigments that give beets their color move all the way through your  digestive system without breaking down. That happens sometimes because our bodies  aren’t that good at absorbing them, so it’s basically in one end and out the other.

The good news is, beeturia is completely  harmless, although it can be alarming if you’re not expecting it,  because it looks a lot like blood. But if you’re only seeing red  after you’ve eaten some beets, chances are, you’re looking at beeturia. Oddly, this only affects about 1 in 10 people.

And it seems to be more common in people  whose bodies have trouble absorbing or breaking down their food, like people  with low iron or low stomach acid. But, bottom line, there’s no need to  panic, and once you’re done eating the beets, things should go back to normal in a couple days. But beets aren’t the only food that  can make parts of you change color.

Now and then, the pigments in your food  can even change the color of your skin. So, you might have heard that eating too  many carrots can turn your skin orange. Now, it’s pretty rare, but it is true!

That one’s for you, Bugs Bunny! Carrots get their color from an  orange pigment called beta-carotene, and they’ve got a bunch of it. Most of the time, our bodies quickly  turn these pigments into vitamin A, which your body uses to keep your  immune system and vision in good shape.

But if you eat more beta-carotene than  your body can process, that extra pigment will just float around in your bloodstream  and dissolve into your body’s fat. It tends to get drawn into  the top layer of your skin, which has a lot of fatty compounds called lipids. And that can give your skin an orange  hue, appropriately called carotenemia.

You’ll see it most easily in places like  your palms and the soles of your feet, where you have thicker layers of skin. Fortunately, as unusual as it may  look, carotenemia is completely benign. And it takes a lot to get it.

You’d have to be eating around 10  carrots a day for weeks at a time before you’d start turning orange. And funnily enough, it’s not just  carrots that can cause this condition. Any food high in beta-carotene can do  it, including mangoes, sweet potatoes, and even some not-so-orange  foods like asparagus and spinach.

And that one’s for you, Popeye! But once you back off the carrots,  or whatever it is you’ve eaten, your skin should go back to  normal within a few months. Sometimes, though, that  orange-y tinge from carotenemia can be mistaken for a less  harmless condition called jaundice.

Jaundice happens when a yellow pigment  called bilirubin builds up in the blood. We all have some bilirubin in us — it  gets produced as our liver breaks down dead red blood cells, and it’s  a completely natural process. But bilirubin isn’t usually the final product.

Normally it keeps getting broken  down into a colorless compound that gets flushed out in our poop. But now and then, bilirubin builds  up faster than it can be broken down. And sometimes that’s because more  red blood cells are dying than usual.

Other times, it’s because the body isn’t  able to get rid of the bilirubin properly, which can be a sign that something’s  up with the liver or gallbladder. And that could be because of some other condition, like viral hepatitis, alcohol  misuse, or gallstones. Either way, when you end up with  too much bilirubin in your system, it starts leaking out of your blood  vessels and into the surrounding tissues, making your skin and eyes look yellow.

It can look a little like carotenemia,  except it doesn’t just affect the skin. Jaundice also will make the whites of  your eyes and the inside of your mouth look yellow, so that’s one simple  way to tell these conditions apart. And if it does seem like it could be jaundice, that’s definitely something to see a doctor about.

Thank you to DeleteMe for  supporting this SciShow video! DeleteMe works to keep your  personal information personal. They remove stuff like your phone number  and address from public search results, giving you back more control  over who you share it with.

That way, you have less to worry about when it comes to identity  theft and phishing scams. I’m sure you steer clear of responding  to emails that you don’t recognize. But your Aunt Mary might not be  as vigilant about that stuff.

So DeleteMe offers family plans to  take care of all of your loved ones. Including the ones that don’t spend  as much time on the internet as you do. Since the ways companies collect, share, and sell your data are constantly changing, DeleteMe is continuously improving and  evolving to address these challenges.

They’ll even remove your  personal information continuously throughout the year to address  anything new that pops up. If you want to get started, go to and use promo code SCISHOW at checkout. You’ll get 20% off DeleteMe US consumer plans!

And now, back to the show. Now, sometimes what changes  color isn’t the skin itself, but rather, what comes out of it. Chromhidrosis is a disorder that makes  people sweat in different colors, like yellow, green, blue, or black.

Sometimes people will get green chromhidrosis after they’ve ingested copper which  then dissolves into their sweat. Copper combined with air and  water can turn into copper oxide, which has a green color,  like the Statue of Liberty. Other times, certain dyes in  medications or food can cause it, but you’d have to be eating a lot of food  dye in order to start sweating the rainbow.

And other times, the culprit is bilirubin again. If you have too much  bilirubin in your bloodstream, you might end up sweating some of it out. And it turns out, when yellow  bilirubin is exposed to air, it can get oxidized and become  the green pigment biliverdin!

Just like with jaundice, high  levels of biliverdin could be a sign that there’s something up with your  liver that you need to take care of. If you find and address the underlying  issue, you’ll get rid of chromhidrosis. Which is probably pretty good, since  I hear it’s not easy being green.

Here’s looking at you, Kermit! Often, these color changes we  see on the outside of our bodies hint at something going on deeper inside. And that’s also the case with  a condition called blue sclera.

Your sclera is the white part of your  eye… except, sometimes it’s not white. In some people, it takes on a bluish hue. The sclera is made up of a thick  network of collagen fibers, and usually they’re totally opaque.

Collagen is a fiber-like protein that  makes up a lot of our connective tissues and gives the sclera its stiffness. But certain conditions can  cause these fibers to thin out, letting the deeper, bluer  layers of the eye show through. When that happens, you’re seeing the uvea, a part of the eye named after  the Latin word for “grape.” One of these conditions is brittle bone disease.

It’s caused by a mutation in  a gene that produces collagen, and blue sclera is one of the common  symptoms doctors use to detect it. Other connective tissue disorders that  affect collagen can also produce blue sclera, such as Marfan syndrome  and Ehlers-Danlos syndrome. But blue sclera can have non-genetic causes too, such as iron deficiency, since iron  is critical for producing collagen.

Fortunately, blue sclera is  usually harmless and painless, and it doesn’t necessarily need to be fixed. But, if you do suddenly notice the  whites of your eyes turning blue, it’s worth having a doctor check it  out, just in case it’s being caused by some underlying condition  that needs to be treated. Eyes aren’t the only thing  that can turn blue, though.

Starting in the nineteenth century, a  Kentucky family known as the Blue Fugates had a long line of descendents with blue skin. They all had a condition called  methemoglobinemia, or MetHb for short. People with MetHb have high levels  of a compound called methemoglobin.

It’s a form of hemoglobin, the protein  in red blood cells that carries oxygen around the body — except that  methemoglobin can’t carry oxygen. So, people with MetHb have less  oxygen in their blood overall, which makes their blood darker. Inside the body, that blood is a deep brown color.

If you have dark skin, you  might never know you have MetHb without taking a genetic test. But in people with lighter skin, that  darker blood makes the skin look blue. This condition is often  caused by a mutation in a gene that’s in charge of changing  methemoglobin into regular hemoglobin.

It’s a recessive mutation,  so people can carry one copy without developing MetHb themselves. But in the case of the Blue Fugates, some children inherited the mutation  from both parents… and were born blue. This type of MetHb often doesn’t  come with any other medical issues, and people who have it can live healthy lives.

In fact, many of the Fugates  lived well into their 80s and 90s! There is a more deadly version of inherited  MetHb that affects the whole body, not just the red blood cells, and people  who have it usually die in infancy. But not the Blue Fugates.

In some other cases, people without  the genetic mutation can acquire MetHb after taking certain medications that  react with blood to make methemoglobin, and this form of MetHb can be extremely dangerous. But if there are no serious health  issues and the only symptom is blue skin, there is one simple treatment. Just add more blue!

Methylene blue is a salty solution,  and true to its name, it’s blue. And oddly enough, injecting  this blue solution into people with blue skin actually  clears up their complexion. Once this medication enters the  body, it starts turning methemoglobin back into hemoglobin, making  up for the mutated gene.

And it works fast. Some of the descendants of the blue  Fugates were treated with methylene blue in the 1960s, and it cleared  their blue tinge within minutes! In general, having a bluish  complexion is known as cyanosis.

And it can have different causes  and come in different shades, including a more purple-y one. This particularly purple pigmentation comes from a condition called Raynaud’s disease. Raynaud’s disease happens when a  person’s blood vessels narrow too much in response to cold or stress, which makes  it difficult for blood to flow properly.

It’s most noticeable in the  fingers, but Raynaud’s disease can also affect other extremities,  like your toes, ears, and nose. When your body gets cold, it’s totally  normal for your blood vessels to contract, to reduce the amount of heat  that gets lost through your skin. This reaction can also  happen in response to stress.

But in Raynaud’s disease, the blood vessels  narrow too quickly and for too long. If you have lighter skin, this lack of blood  flow can make your fingertips turn white at first, then purple-ish as the  deoxygenated blood darkens under your skin. Finally, they might turn red as  your blood vessels relax again and your circulation comes back.

If you have a darker skin tone,  Raynaud’s disease may show up as more pale than purple. Raynaud’s can feel a little uncomfortable. The lack of circulation can make your  fingers and toes feel numb or cold.

And as the blood returns to your blood  vessels, you may feel pins and needles. But if there are no other health  conditions causing your Raynaud’s, it seems to be more inconvenient than dangerous. While there’s no cure yet, many people  can manage their Raynaud’s disease with lifestyle changes, like  keeping warm and avoiding stress.

And if it’s not a result of some other condition, Raynaud’s can sometimes even go away on its own. So, as unnerving as it might be  to find your hands or your eyes or some other part of you  changing color… it happens! And usually it’s telling you something  about what’s going on under the skin.

It might be a sign that it’s time  to go get checked out by a doctor… or maybe you just need to cool it on the carrots. [♪ OUTRO]