Name: 有夠困擾！到底頭皮屑是怎麼形成的又該怎麼去除呢？！ (What causes dandruff, and how do you get rid of it? - Thomas L. Dawson)
Uploaded: 2021-10-15T21:01:30.000Z
Duration: 5 min 5 s

Here in this abundant forest, Malassezia is equipped with everything  it could ever need.

在這片富饒的森林中，馬拉色菌擁有一切所需。

In fact, Malassezia is a type of yeast that lives and dines on all of our scalps.

事實上，馬拉色菌是一種酵母菌，它在我們的頭皮上生活和吃飯。

And in about half of the human population, its activity causes dandruff.

它的活動讓世界上一半的人口長頭皮屑。

So, why do some people have more dandruff than others?

那麼為什麼有些人的頭皮屑比較多？

We might consider ourselves individuals, but we're really colonies.

我們可能認為自己是個體，但我們其實是殖民地。

我們的皮膚上住著數十億微生物。

Malassezia yeasts make themselves at home on our skin shortly after we're born.

在我們出生後不久，馬拉色酵母菌就在我們的皮膚上安了家。

Follicles, the tiny cavities that grow hairs all over our body, make for especially popular living quarters.

我們遍佈全身的毛髮都是從毛囊長出來的，而這也是馬拉色菌最愛的住所。

Malassezia are fond of these hideouts because they contain glands that secrete an oil called sebum that's thought to lubricate  and strengthen our hair.

馬拉色菌之所以喜歡這些藏身之處，是因為它們含有一種腺體，會分泌出一種叫做皮脂的油，而一般認為這種油能潤滑和強韌毛髮。

Malassezia evolved to consume our skin's proteins and oils.

馬拉色菌進化為以皮膚的蛋白質和油為食。

And because of its many sebum-secreting follicles, our scalp is one of the oiliest places on our body—and consequently, one of the yeastiest.

由於皮膚有很多分泌皮脂的毛囊，頭皮就成了全身最油的地方之一，也因而成為酵母菌最多的地方之一。

As these fungi feast on our scalp's oils, dandruff may form.

這些真菌酵母在頭皮上大快朵頤時，頭皮屑就可能會形成。

This is because sebum is composed of both saturated and unsaturated fatty acids.

這是因為皮脂是由飽和脂肪酸和不飽和脂肪酸所組成的。

Unsaturated fats, on the other hand, contain double bonds that create an irregular kink in their structure.

但另一方面，不飽和脂肪含有雙鍵，會在結構中產生不規則的扭結。

Malassezia eat sebum by secreting an enzyme that releases all of the oil's fatty acids.

馬色拉菌會分泌一種酶，將油脂分解為脂肪酸來吃。

But they only consume the saturated fats, leaving the unsaturated ones behind.

但他們只會吃飽和脂肪，並把不飽和脂肪放在一邊。

These irregularly shaped leftovers soak into the skin and pry its barrier open, allowing water to escape.

這些形狀不規則的剩菜滲入皮膚，撬開屏障，讓水逸出。

The body detects these breaches and responds defensively, causing the inflammation that gives dandruff its itch.

身體會偵測到這些破壞，並作出防禦性的發炎反應，而頭皮屑之所以會癢就是因為這些發炎反應。

It also makes the skin cells proliferate to repair the damaged barrier.

頭皮的皮膚細胞也會增生，以修復損壞的屏障。

Usually, our skin's outer surface, or epidermis, completely renews itself every two to three weeks.

通常身體的皮膚表面，也就是表皮，每二到三週會完全更新一次。

Epidermal cells divide, move outwards, die, and form the skin's tough outer layer, which gradually sheds off in single cells far too small to see.

表皮細胞會分裂，向外移動，死亡，形成皮膚堅韌的外層，然後小到眼睛都看不到的細胞一個個逐漸脫落。

But with dandruff, cells churn out quickly to correct the broken barrier, meaning they don't mature and differentiate properly.

但為了修補損壞的屏障，頭皮細胞必須快速增生，造成細胞未適當地成熟和分化。

Instead, they form large, greasy clumps around the hair follicle that are shed as visible flakes.

相對的，它們會在毛囊周圍形成一團一團的油脂，並在脫落時變成一片片肉眼可見的碎屑。

This is how Malassezia's voracious appetite and our body's reaction to its by-products lead to dandruff.

馬拉色菌貪婪的胃口，和我們的身體對它副產品的反應就是頭皮屑生成的原因。

Currently, the most effective way to get rid of dandruff is by using antifungals in things like shampoos, applied directly to the scalp, to kill Malassezia.

目前，擺脫頭皮屑最有效的方法是使用抗黴菌的洗髮精，把它直接用在頭皮上來殺死馬拉色菌。

For those who experience dandruff, it usually comes and goes as sebum secretions vary throughout one's lifetime due to hormonal changes.

對於有頭皮屑困擾的人來說，這種症狀通常會來來去去，因為皮脂分泌物的多寡在一生中會因荷爾蒙的變化而改變。

But despite the fact that Malassezia colonize everyone to a similar extent, not everyone gets dandruff.

儘管馬拉色菌多多少少都會殖民在每個人頭上，但並不是每個人都會有頭皮屑。

Do people with dandruff have a certain genetic predisposition?

會長頭皮屑的人是否有某些特殊基因？

他們皮膚的屏障滲透率更高嗎？

Scientists are currently investigating if people with dandruff do, in fact, lose more water through their scalps, and whether this is what's leading their skin cells to proliferate.

科學家目前正在研究頭皮屑患者的頭皮是否真的更容易脫水，以及他們的頭皮細胞是否因此而增生。

Researchers are learning that Malassezia communicate with our immune system using small, oily molecules called oxylipins that regulate inflammation.

研究人員最近得知，馬拉色菌使用稱為氧脂素的油性小分子與免疫系統溝通，而氧脂素可以調節發炎反應。

If they can find a way to inhibit inflammatory oxylipins and boost anti-inflammatory ones, they could develop new treatments.

如果能有辦法抑制引起發炎反應的氧脂素，同時增加抗發炎的氧脂素，他們就能開發出新的療法。

Scientists are also investigating if there's any benefit to our relationship with Malassezia.

科學家們也在研究馬拉色菌對我們是否有益處。

They hypothesize that dandruff, which can be uncomfortable and embarrassing for us, creates a reliable, oily food source for the yeast.

他們提出的假設是，儘管頭皮屑讓人不舒服和尷尬，對酵母菌來說，卻是可靠又富含油脂的食物來源。

But dandruff isn't contagious or a great threat to our health.

但頭皮屑不會傳染，對我們的健康也沒什麼威脅。

And Malassezia seem to excel at defending their territory, our skin, from other, more harmful microbes like Staphylococcus aureus.

馬拉色菌好像也很擅長保護他們的領地，也就是我們的皮膚，免受金黃色葡萄球菌及其他有害微生物的危害。

So, while scientists have gotten to the bottom of many mysteries surrounding this condition, it must be said: dandruff remains a head-scratcher.

因此，儘管科學家已經揭開圍繞這種疾病的許多謎團，但我們還是要說：頭皮屑還是讓我們不停搔頭。

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有夠困擾！到底頭皮屑是怎麼形成的又該怎麼去除呢？！ (What causes dandruff, and how do you get rid of it? - Thomas L. Dawson)

constantly

susceptible

immune

properly