using a staggering 80 liters of toothpaste.

消耗80公升的牙膏

And such a routine parts of our everyday lives,

這樣一個每天生活中的習慣動作

but there is only I think about it is when it runs out.

可是我們只有在牙膏快用完時才會想起它

Now that’s a shame because toothpaste is fascinating stuff.

這有點不妙，因為你還不懂得牙膏的好

Tooth care remedies have been around for thousands of years.

牙齒保健已經持續了有千年之久

The world’s oldest surviving formula is Egyptian

世上現存最古老的配方來自於埃及

and it was made from mint, flowers, salt and pepper.

有薄荷、花、鹽巴、還有胡椒

It dates to the 5th century AD and by all accounts it worked very well.

它源起於西元五世紀時，而且據說非常有效

Although it did have the nasty side effects of making your gums bleed.

僅管它有著讓你牙齦流血的副作用

Having said that, it was far less hazardous than some 20th century brands.

但必須說，這相較於20世紀的部分牌子來得安全多了

In the 2nd world war, German scientists from the nuclear industry

在二次大戰時，德國核能工業界的科學家

developed a radioactive toothpaste with thorium for the domestic home market.

利用釷元素發展出一種具有放射性的牙膏，供給當地家庭市場

It cleans. It kills germs. It’s radioactive.

它有效清潔、殺死細菌、還有放射性

Fantastic!

太棒了！

Now why didn't that catch on?

但是為什麼沒有流行起來呢？

Say thorium wasn’t a great idea but other additives were much more successful.

釷並不是一個好選擇，但其他添加物都還蠻成功的

In 1901, a dentist in Colorado Springs noticed that locals had far fewer cavities than was the norm.

1901年，科羅拉多溫泉市的一名牙醫注意到當地民眾的蛀牙率遠低於標準

The reason was eventually tracked down to high natural levels of fluoride in the water.

追蹤後，發現原因是水中高含量的天然氟化物

From this basic observation, fluoride quickly became the dental one additive of choice.

基於這樣簡單的觀察結果，氟化物快速地成為了添加物的選擇之一

So what goes into modern toothpaste?

那現代的牙膏呢？

How does it work?

是怎麼運作的？

Well the number one ingredient is something abrasive.

首要成分是一種具有磨蝕作用的成分

You know something to scrub the pearly whites

你知道的，就是用來擦拭你珍珠般皓齒的東西

For this, toothpaste manufacturers typically use baking soda or chalk or even silica which is a refined type of sand

通常製造商都選用小蘇打粉、白堊粉、或是矽土，一種細緻的顆粒

and many add whitener, flavouring, something to make it foam.

很多還會加漂白劑、調味劑、使它起泡的成分、

Something to bind it all together and finally fluoride.

可以把他們全部混在一起的成分，最後是氟化物

Now did you know you can make your own toothpaste out of simple household ingredients?

你知道只要利用家裡簡單的材料，你也可以做一條專屬於你的牙膏嗎？

For this recipe, all you need to do is mix three tablespoons of baking soda with 1 tablespoon of salt.

按照配方，你需要3茶匙的小蘇打粉，跟1茶匙的鹽

Then add three teaspoons of glycerin.

3茶匙的甘油

Mix them all together with a dash of water.

和少許的水混合

And finally add 1 teaspoon of peppermint and hey presto!

最後加上1茶匙的薄荷油，完成了！

Do it yourself toothpaste.

做你個人專屬的牙膏

For a proper test of its effectiveness,

為了測試這是不是真的有效

I’m going to stain my teeth with licorice.

我要用甘草把我的牙齒染色

I have some very sugary pop.

接著要喝這杯超甜的汽水

Now it firms them up.

我的牙齒應該都佈滿顏色了

Now my teeth feel awful so let’s put this home-made toothpaste to the test.

我覺得我現在的牙齒蠻糟的，來使用這條自製的牙膏測試一下效果吧

I feel that! Gosh! Seriously, feel good. I feel much better.

我感覺到了！天啊！感覺還不錯，我覺得好多了

It tastes quite minty, very abrasive.

薄荷味蠻重的，摩擦力很強

It’s incredibly salty but it’s cleaning my teeth.

真的很鹹，不錯確實有在清潔我的牙齒

I feel so much better.

我感覺好超多

How about my teeth looks a little bit cleaner?

牙齒是不是也變得比較乾淨一點了？

Hmm. Home-made toothpaste! It works!

嗯，自製牙膏，它真的有效！