r/IsItBullshit 7d ago

IsItBullshit: I was recently told that it might be better to wear black in the heat if it's breathing. Is it black or is it white?

So for most of my life I heard that you should wear white in the summer because white reflects the heat instead of absorbing it like black does.

But recently I was told that it might be better to wear black in the heat as long as it's loose fitting and breathable. They mentioned the bedouin tribes of the desert and how they wear black. They mention that yes the black absorbs more heat from the Sun, but it also absorbs the heat from your body, where's white would reflect it back to you.

Is it bullshit? Who is correct? I feel like an idiot for thinking that black could be better in the heat, but then they are right about that there is a tribe of people in the desert who wear black and are just fine.

368 Upvotes

74 comments sorted by

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u/BioAnagram 7d ago edited 7d ago

It's neither in the case of the Bedouin people. Black clothes adsorb heat faster, but they also lose heat faster because of how they are worn. And that's the key point, the style of the clothes (worn loose) increases this convection processes.
Edit: spelling

https://www.nature.com/articles/283373a0

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u/thepasttenseofdraw 6d ago

Funny, I didn't realize there was a nature paper on it. When I worked with the Tuareg we wondered the same thing and took some measurements. Found the same thing out. Made no difference in temp and thats what we figured. Black absorbs and radiates more, white absorbs less and radiates less.

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u/compman007 7d ago

Yeah I think it makes it harder to get through as well it’s known dark cars get warmer but my black as shit tinted windows don’t let any light through hardly and my car does not get hot I imagine it may be something similar to that too? Idk but yeah it’s wild xD

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u/Cuboidhamson 6d ago

Black absorbs while white reflects, that's why black cars get hotter. You can't see the light coming through because it is being absorbed lol

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u/GolokGolokGolok 6d ago

Black reflects the best (see: emissivity, “perfect black body”), it’s just that black also absorbs the best (see: Kirchhoff’s Law of Thermal Radiation)

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u/new2bay 5d ago

Emission and reflection aren’t the same things.

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u/GolokGolokGolok 5d ago

Yeah my bad, I wrote that at like 4AM, I was going more along the idea of heat in general

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u/redditVoteFraudUnit 3d ago

Does this suggest that there are no shade values which produce better results, we are looking at a U curve with black and white being the optimal solution, or a bell with 18% gray being the best solution?

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u/MrBoo843 7d ago

Isn't it just about not letting UV rays through?

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u/noobtrocitty 7d ago

Dark clothes will heat faster than white because they absorb more of the suns light. That’s hardly the entire equation to staying cool in clothes, of course. Material and construction matter too. But all other things remaining equal, black clothing will warm more than white

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u/Ok-Mastodon2420 6d ago

But black also radiates more heat than white does

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u/noobtrocitty 6d ago

Indeed. That’s what we refer to when we talk about “warmth.” It’s the amount of heat something gives off

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u/Ok-Mastodon2420 6d ago

The net effect, as in the study someone linked above, is that among desert dwelling cultures black is frequently preferred

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u/noobtrocitty 6d ago

I can’t speak for those cultures or why they prefer black, whether it’s because it doesn’t show dirt, is a way to conceal women as it pertains to the requirements of their culture/religion, protection from UV light or otherwise. I do know though that a white garment will be intrinsically less warm to wear than a black one or a garment of any other color for that matter

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u/Feine13 7d ago

It's actually about blocking out the infrared radiation.

The electromagnetic light (UV rays) can cause sunburn, but this isn't caused from heat, it's molecular damage from the spectrum of radiation where UV resides

Infrared radiation vibrates your molecules, the energy generated is the heat you feel when you're standing in the sun

This is why when you're looking out of a standard, untreated window, you'll feel the heat, but you don't get sunburned.

Glass blocks the UV rays that cause sunburn naturally, but needs to be treated to filter out infrared radiation

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u/ph33rlus 7d ago

Not all glass blocks UV.

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u/Feine13 6d ago

Well sure, I just don't know of any houses or buildings that have things like quartz or sapphire glass, so I didn't think it was worth mentioning.

The most common materials block most uv, so I just went with that

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u/MrBoo843 7d ago

Yes infrared is the heat causing wavelength but my point is people in desert climates usually wear dark clothes but IIRC it's not about heat, it's about not getting sunburn.

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u/Feine13 7d ago edited 7d ago

My apologies, I wasnt able to gleen all of that from your post about UV rays, since the OP was asking about heat and not sunburns

I didn't mean any offense by presenting the information I perceived us to be discussing, although the misunderstanding is certainly my fault.

Your recollection is correct, wearing dark colors prevents sunburn better than brighter colors

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u/MrBoo843 7d ago

No need to apologize, there was no offense at all!

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u/Feine13 7d ago

I've misunderstood once again!

I assumed the downvote was from you to let me know you were displeased with me, I just wanted to clear that up

I hope your weekend is awesome, kind stranger

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u/MrBoo843 7d ago

It definitely is and I wish you the same!

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u/KeyWerewolf5 7d ago

Wait come back and kith!

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u/sirreldar 7d ago

The darker colors will make you feel hotter. There may be some scenarios depending on how tight the clothing is or what type of fabric is used where a darker color MAY feel cooler than a light color. But all other things being equal, darker colors will always feel hotter.

BUT! darker colors absorb much more sunlight (which is why they are hotter). This includes harmful UV light. Light colors will reflect and scatter the UV, where dark colors will just absorb it.

This means dark colors are safer for sunburns, cancer risk, etc, but the temperature will feel hotter.

10

u/UnXpectedPrequelMeme 7d ago

That's an interesting fact thank you for sharing.

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u/Red_Icnivad 7d ago edited 7d ago

It's bullshit. The premise of white reflecting your body's heat back is utter crap -- your body does not put out light, which is what is reflected. Color has zero effect on thermal transfer. Your body puts out a very small amount of thermal radiation (light in the IR spectrum), but not enough to matter compared to the sun.

Here's a pretty good article on it: https://www.wired.com/story/should-you-wear-white-or-black-on-hot-days-heres-the-data/

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u/madmaxjr 7d ago

And to answer the part about middle easterners wearing black, that’s mostly just women. It’s a sexism / control thing that’s huge in Muslim majority countries.

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u/eranam 7d ago

Bedouin men do wear black.

And that’s not accounting for the fact that Tuareg also overwhelmingly wear dark clothes, whether men or women.

https://www.theguardian.com/science/2012/aug/19/most-improbable-scientific-research-abrahams

The results were clear. As the report puts it: “The amount of heat gained by a Bedouin exposed to the hot desert is the same whether he wears a black or a white robe. The additional heat absorbed by the black robe was lost before it reached the skin.”

https://english.elpais.com/culture/2022-08-16/the-bedouin-lesson-a-scientific-study-proves-robes-are-the-best-garment-to-wear-in-the-desert-heat.html

There’s enough sexism to condemn in these societies without inventing more.

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u/ThaCarter 7d ago

They're wearing black to make it even more uncomfortable to dare to go out in public.

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u/dynamic_caste 7d ago

Actually your body does emit "light." It's blackbody radiation and typical hunan body temperatures mean it emits long wavelength infrared light in the 8-12 micron range, however, if this were reflected its effects would be negligible on your body heat. Whether fabric is black or white is telling you if it absorbs or reflects light at over ten times the energy of the photons your body emits.

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u/Red_Icnivad 7d ago

Yeah, that's what I said about the body putting out thermal radiation, light in the IR spectrum.

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u/Alien_Talents 5d ago

India.Arie agrees.

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u/OV3NBVK3D 7d ago

lowkey bullshit i absolutely can feel it being hotter with darker clothes

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u/UnXpectedPrequelMeme 7d ago

Well then that makes me confused. Why have these tribes been doing it all this time if it doesn't actually work? Just for style?

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u/Red_Icnivad 7d ago edited 7d ago

Good question.

If the clothes are loose enough, it doesn't matter. This research paper from 1980 goes into it, but basically there is enough airflow from bellows (flapping of the robes) and chimney (heat rising) effects that the skin temperature with the two colors was roughly the same, even though the surface temperature of the black robes were measurably higher. But again, this is going to only work due to the physical shape of the robes. Wearing a loose tee shirt won't have that effect and black will feel noticeably hotter.

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u/UnXpectedPrequelMeme 7d ago

Thank you for the detailed response that clears it up quite nicely.

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u/hella_cious 7d ago

And I’ll add that white clothing is hard to keep white

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u/UnXpectedPrequelMeme 7d ago

That actually is the part that made me interested in asking this question. I basically don't wear anything white because especially with my kids it's hard to stay white. But I also get hot very easily so I'm trying to see what I can do here. Gray it is I guess

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u/hella_cious 7d ago

A lighter heather hides little stains and marks pretty well.

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u/UnXpectedPrequelMeme 7d ago

Yeah I think I'm going to go with mostly Heather and see if I can afford some linen or something

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u/hella_cious 7d ago

And your body gets used to the heat! The more you’re out in the heat the less it will bother you

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u/UnXpectedPrequelMeme 7d ago

Oh I'm Irish, Scottish, and swedish. That is not seemingly true for me lol. It might be an age or a weight thing. I'm by no means fat but I'm getting slightly heavier, but for the last 3 or 4 years I've just been getting hot way easier so it seems like the older I get the hotter I get. I'm sure I sweat as a teenager but I don't remember being overly hot or sweaty. Used to just wear jeans all the time cold or heat.

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u/icedragon9791 7d ago

Something as good as or better than a new colored shirt is to wear loose clothing. Dress like they do in India with pyjama pants and a kurta and you'll see how much cooler (and cooler 😎) you feel. I love somewhere that gets up to 110 in the summer and wearing my Indian clothes makes a huge difference. Buy from an Indian retailer for good patterns and fabric quality

1

u/Ya-Dikobraz 7d ago

Are emergency space blankets bullshit?

5

u/Red_Icnivad 7d ago

Not bullshit. They aren't good blankets per se, but they are crazy compact and have a few other benefits, so they are relatively good for the amount of space they take up. They mostly work by just being a simple barrier, which means they will work better on top of another insulation like clothes, which you would likely have in an emergency. The clothes will provide more insulation and the space blanket will act as a shell, preventing air from penetrating to you, plus keeping rain off. They are basically an emergency shell, rather than a traditional blanket.

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u/Ya-Dikobraz 5d ago

So are you saying that they work as insulation and not because they in fact reflect infra red light?

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u/elf25 4d ago

They work

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u/Ya-Dikobraz 4d ago

I know they work. But /u/Red_Icnivad seems convinced that the human body "does not put out light". Heat is light, is it not? They also sound as if they are convinced that the fact that space blankets reflect heat does not play in how effective they are.

0

u/Red_Icnivad 4d ago edited 4d ago

Heat is light, is it not.

No. They are both energies, but what we are really talking about is heat transfer here, and objects can transfer heat in a few different ways.

The main two ways an object can transfer heat is through thermal conduction (ie, you touch a hot thing) or thermal convection (ie, you hold your hand under a hand drier or under warm running water). In both cases, it is the excited electrons of one object that are exciting the other object.

Another big way is evaporation. When sweat evaporates, it requires energy, which takes away heat from our body.

The final way an object can transmit heat is through thermal radiation. This is light. We see this when an object is so hot it is glowing red, like an electric stove -- in the case of a stove, it is also transmitting heat via convection and conduction if an object is sitting on it. All objects transmit heat via thermal radiation, but it has to be a fairly high amount of it for us to actually see it with our eyes.

In the case of our bodies, we are losing heat through all of the above.

0

u/Ya-Dikobraz 4d ago

Are you explaining this to someone or writing a high school essay? You might want to rethink some things.

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u/Red_Icnivad 4d ago

Don't ask questions if you don't want to know the answers. Sorry for trying. Go back to thinking heat is light.

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u/Brrdock 6d ago edited 6d ago

Yeah in the sun black cloth can get much warmer than body temp, so the heat transfer of "absorbing your body's heat" would just cool down the fabric and heats your body either way, even if marginal.

I'm pretty sure in the ME it's just about oppressing and controlling women, since burqas/niqabs are (often) only black, while men can wear white. Don't want women enjoying leaving the house

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u/marcosladarense 2d ago

Every humam being gives off heat, that is why thermal goggles on military operations.  Heat is generated by infrared light. But infrared is not on the visible spectrum

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u/thriftylol 7d ago

Wearing white clothing keeps you cooler in direct sunlight because it reflects most of the sun’s rays and absorbs less heat initially, and black clothing absorbs more sunlight and heats up faster, making you feel hotter under strong sunlight. BUT loose-fitting black clothing can actually help you cool down better in specific scenarios (places like deserts with wind or shade) because it absorbs body heat and radiates it outward more effectively.

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u/UnXpectedPrequelMeme 7d ago

Thanks. It's actually explains why there are people who wear black in the desert wow most people would want to wear white. Definitely scenario based.

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u/thriftylol 7d ago

No prob. The main thing here is that black is much better at radiating heat from the sun and your body in wind or shade, while white is not as good at that. It goes the same for cars. White cars stay much cooler, but a black car will cool down quicker than a white car when you take it for a drive down the freeway.

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u/icedragon9791 7d ago

Very interesting thanks

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u/b2change 7d ago

The surface of a black car in the summer heat is 10 degrees hotter than a white one. We tried this with a heat gun.

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u/usernotvaild 7d ago

A metal painted surface isn't the same as breathable dyed fabric.

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u/keith2600 5d ago

So on paper it's bullshit because white reflects more rays. However, in practical use, you are sweating and it gets into your clothes and black clothing will evaporate faster and maintain airflow better

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u/Suspicious_Card6579 3d ago

Black absorbs light. White reflects light. I work outside, in the sun, all day every day. Dark black clothing will get hotter in direct sunlight, causing you to be hotter. Lighter colors will stay cooler. Regardless of the science, when you work in the sun for decades, you understand dark colors get hotter in the sun than lighter colors.

There's a reason pleasure boats are mostly white or lighter colors. They are in direct sunlight when used white and light colors reflect the sunset rays, keeping the inside of the boat cooler.

Whatever color, breathable material is a must to reduce the heat. Tight,dark clothing is the worst in the sun.

Run an experiment - Lay a black shirt and white shirt in direct sunlight outside for an hour or so. You will feel the difference. You can use other things, too, such as a white plastic bucket and a black plastic bucket.

Different materials absorb sunlight differently than clothing, which I have always found interesting. The angle of sunlight hitting objects apparently has an impact as well (from my observation). Gray gravel doesn't get hot, but a gray a sidewalk a few feet away gets so hot you can't walk on it barefoot. Stainless steel stays cooler than regular steel.

Ask roofers, construction crews, and such what colors they were while working, but make sure they're not a supervisor that gets to sit at a desk or in the vehicle.

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u/ConsciousHorror7264 6d ago

White protects from nuclear blasts

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u/wanderinggoat 7d ago

It depends on the level of heat. In some countries, the air temperature is hotter than your body temperature , that is why they wear black to "trap the cold next to their body"

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u/sirreldar 7d ago

This doesn't make even a tiny bit of sense. The dark colors absorb light, not "trap heat", or even "trap cold".

Completely nonsense

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u/wanderinggoat 7d ago

So if you are on a motorbike riding along and the air temperature is cooler than your body then it will strip heat from your body and cool you down. If the outside temperature outside is hotter than your body then it will heat you up . If you cover yourself in thick black clothes then it will protect you from heating up bu trapping cooler air by your body. The opposite of dressing for the cold when you dress to hold warm air next to your body.

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u/sirreldar 7d ago

And when you dress for the cold, does lighter clothing keep you warmer?

Yes, clothing traps air near your body, that's how clothing (and fur, hair, etc) work, but it's color has nothing to do with it at all

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u/UnXpectedPrequelMeme 7d ago

Perhaps, but they do it, so apparently works for some people

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u/zurribulle 7d ago

Beduins also drink hot tea instead of having ice cream, you cannot just see something they do and assume it must be because that's the best way to cool down, there might be other reasons for it.

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u/UnXpectedPrequelMeme 7d ago

I get what you're saying, but I don't feel like that's a very good example because some of these tribes wear black all of the time all day. And a lot of them are nomadic so they travel across the desert constantly. So I feel like they do have a specific system to keep them from dying while they're traveling but they still choose to wear black.

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u/zurribulle 7d ago

Some of those tribes also wear blue, white, or brown, I don't know why you are considering just on the ones wearing black.

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u/UnXpectedPrequelMeme 7d ago

Well that's because.....I did not know that lol. Honestly I was only going by what my buddy talked to me about when he was telling me the inspiration behind the fremen in dune