(单词翻译:单击)
Nothing really beats a steamy shower to relax after a hard workout.
辛苦工作一天后一个雾气腾腾的热水澡简直不能更棒。
And good hygiene is how we protect ourselves from infections, and the social stigma of being smelly.
好的卫生情况能保护大家远离传染病以及身体异味。
But do you really need a daily shower to stay clean, or is it doing more harm than good?
但是真的有必要每天洗澡保持干净么？又或者每天洗澡是否弊大于利？
It turns out, there aren’t any definite rules,
事实上还真没有任何明确条令
but some scientists have recommendations based on what we know about the biology of our skin —
但一些科学家根据我们皮肤生物学——
and what might be living on top of it.
以及生存在皮肤之上的生物知识提出了建议。
Your skin is a giant organ that physically blocks harmful stuff from getting inside your body.
你的皮肤是一个巨大的器官，能够阻挡有害物质进入你的身体。
It’s covered in a bustling community of bacteria, fungi, viruses, and even teeny-tiny arthropods.
皮肤覆盖于细菌、真菌、病毒甚至是极小节肢动物的嘈杂群落之中。
They make up what’s known as your skin microbiome.
它们组成了所谓的皮肤微生物。
For the most part, researchers think that these microbes you carry with you are pretty harmless.
研究员们认为你所携带的这些细菌是无害的。
But as you interact with the world, you can pick up other microbes that could make you sick.
但在和世界的交流过程中，你可能沾上了可致病的其他细菌。
And when you, like, rub your eyes or put food in your mouth,
比如，当你揉眼睛或是将食物送进嘴里时，
your hands can help those germs slip past your skin and get into your body.
你的手可以帮助那些细菌滑到皮肤上然后进入身体里。
That’s why washing your hands with soap is so important, especially if you work in medicine or food service.
这也是为什么用肥皂洗澡如此重要的原因，如果你在医院或食品店工作则更是如此。
See, soap is a surfactant, which means it’s made of molecules that can bind to water and things like dirt, oils, or bacteria.
肥皂是一种表面活性剂，这就意味着它是由可与水以及脏东西、油或细菌等吸附在一起的物质组成的。
This lets you rinse all that junk away.
它能够让你将所有垃圾冲洗走。
And fewer germs means a lower chance of infections.
更少的细菌意味着更低的感染率。
But what about washing the rest of your body?
但清洗身体其他部位是怎样呢？
Well, your skin has glands that are always producing sweat and oils, which cools you down and keeps your skin moisturized and healthy.
你的皮肤中有腺体，腺体总是出汗出油，起到了降温以及保持皮肤湿润健康的作用。
But there’s a fine balance.
这是一个很好地平衡。
Certain bacteria break down sweat, and release smelly molecules like thioalcohols.
某种细菌分解汗并释放气味分子，如硫醇。
And if your skin has too much dirt, dead skin cells, or oils, your pores can get clogged, leading to problems like acne.
如果你的皮肤有太多污垢、死皮细胞或油脂，你的毛孔会被堵塞从而导致皮肤问题，如痤疮。
So showering with soap can help get rid of some sweat and oil, to manage your looks and smell.
所以用肥皂洗澡能够帮助你除掉一些汗和油，让你闻起来香香。
And in some cases, like the night before a surgery,
在一些情况下，比如手术前夜，
a doctor might tell you to shower with an antimicrobial soap, which has extra chemicals to kill microbes.
医生可能会让你用抗菌皂洗澡，抗菌皂中的额外化学物质能够杀死细菌。
If a surgeon is making cuts in your skin, they don’t want any potentially dangerous stuff sneaking in.
如果外科医生要在你的皮肤上切口，他们不希望有任何潜在危险物质钻进去。
On the other hand, showering too often might not be great for you either.
另一方面，太频繁的洗澡对你也没啥好处。
For one, it can mess with the microbes that naturally live on your skin.
比如这样会干扰那些天然生存于你皮肤中的细菌。
And since soap and water wash away oils, your skin might get too dry so the outer layer cracks,
而且肥皂和水能够洗掉油脂，你的皮肤可能会因为太干而裂口子，
making it easier for disease-causing microbes to slip into your body.
这样更容易让致病的细菌溜进你的身体里。
So dermatologists seem to say that daily showers where you scrub everywhere with soap is probably overkill,
所以皮肤科医生会说每天用肥皂洗澡可能会导致过度杀伤，
unless you sweat a lot, like people who work out every day.
除非你经常出汗，比如那些每天锻炼的人一样。
Otherwise, showering every couple of days should be just fine, to keep your skin microbiome healthy and happy.
否则，隔三岔五的洗一次就够了，这样能顾保持皮肤微生物组的健康和舒适。
Thanks to our Patreon patrons for asking this question!
感谢Patreon上观众的提问！
If you want to learn about more about health related topics, check out our sister channel, Healthcare Triage, hosted by Dr. Aaron Carroll.
想要了解更多健康相关话题，请登录我们的姊妹频道——由Aaron Carroll医生主持的Healthcare Triage。
And don’t forget to go to youtube.com/scishow and subscribe!
不要忘记登录我们网站youtube.com/scishow，订阅我们的频道！
