美国国家公共电台 NPR 'Dirt Is Good': Why Kids Need Exposure To Germs

 

LULU GARCIA-NAVARRO, HOST:

It's summertime. And if you have a young kid, chances are they're covered in a film of sweat and dirt. It can be kind of gross. We went to New York Avenue Park in Washington, D.C., and asked parents how comfortable they are with the yucky stuff.

JEANINE MCGINNISS: Probably I was a little bit more of a germ freak. And then once you have a kid, you start getting comfortable with more germs.

DOROTHEA THOMAS: You know, every possible chance that if there is a germ or whatever, I make him wash his hands.

WENDY CHRISTMAS: I work hard to make sure that they're clean.

GERALD SMITH: Make sure they wash their hands constantly, all the time, soap and water.

GARCIA-NAVARRO: A quick survey there of parents Jeanine McGinniss, Dorothea Thomas, Wendy Christmas, and Gerald Smith. But are we too quick to rush kids to the bath at the end of the day? Our next guest says that dirt is good. Dr. Jack¹ Gilbert is professor of surgery at the University of Chicago, and he's co-author of a book for new parents guiding them through the world of germs, the microbiome and obviously dirt. He joins us from our member station WBEZ in Chicago. Good morning.

JACK GILBERT: Good morning, Lulu.

GARCIA-NAVARRO: Why did you write this book?

GILBERT: Well, as a parent - I have two children now - I can say that when I had my first child, I got a lot of different advice on the kinds of things that I should do to look after my kid. If they have a snotty nose, consider taking antibiotics², to make sure their pacifier was always sterilized⁴, to sterilize³ their food and make sure it was always boiled before you gave it to them. And so for me, it was interesting to go back and look at the data, especially after my second child, where I got a lot more lax in terms of how much of that preparation I put in.

And so we went and looked at the literature, went and delved⁵ into the science and tried to understand what we actually knew about the risks that our modern-day children could experience from those kinds of exposures. Turned out that most of the exposures were actually beneficial.

GARCIA-NAVARRO: You mentioned a few of them already, but what are some of the main things that parents get wrong?

GILBERT: Some of the main things are over-sterilizing⁶ their environment, keeping their children from ever getting dirty. So going out into the backyard and playing in the mud, and then as soon as they're filthy⁷, bringing them in and sterilizing their hands with antiseptic wipes and then making sure that none of the dirt gets near their faces. Also keeping them away from animals. It's fine to wash their hands if there's a cold or a flu virus around. But if they're interacting with a dog and the dog licks their face, that's not a bad thing. In fact, that could be extremely beneficial for the child's health.

GARCIA-NAVARRO: Let's get to some of these questions. You tell me good or bad. Hand sanitizer?

GILBERT: Usually bad. Hot soapy water is fine, even mildly warm soapy water is fine. And it's actually probably less damaging to the child's overall health.

GARCIA-NAVARRO: All right, five-second rule. If something falls on the ground, you know, that thing if it's there for under five seconds it's clean, if it's over five seconds you've got to wash it.

GILBERT: The five-second rule doesn't exist. It takes milliseconds for microbes to attach themselves to a sticky piece of jammy (ph) toast, for example. But it makes no difference. Unless you dropped it in an area where you think that could be a high risk of extremely dangerous pathogens, which in every modern American home is virtually impossible, then there's no risk to your child.

GARCIA-NAVARRO: All right. Wash a pacifier or lick it if it falls on the ground?

GILBERT: Lick it every time. A study of over 300,000 children showed that parents that lick the pacifier and put it back in, their kids developed less allergies⁸, less asthma⁹, less eczema. Overall, their health was stronger and more robust¹⁰.

GARCIA-NAVARRO: And how often should I give my daughter a bath? This is a very important question, by the way, because she hates them.

GILBERT: I know, exactly. Especially when they're small children under the age of 6 months, so infants up to about 18 months, you don't need to get them off every day. In fact, you could go for a couple of days. Wiping down the area with a warm wet cloth. Overall, over-washing can actually damage the skin and lead them to have a higher likelihood of infections and over-inflammatory reactions like eczema.

GARCIA-NAVARRO: One of the things that we are seeing, especially in America, is the rise of allergies. Do you think these two things are linked because we try to protect them so much that, you know, the unintended consequence of that is that actually they are more susceptible¹¹ to things like allergies?

GILBERT: Absolutely. So the basic premise¹² is that in the past, we would have eaten a lot more fermented¹³ foods, which contain bacterial¹⁴ products and bacteria. We would have allowed our children to be exposed to animals and plants and soil on a much more regular basis. Now we live indoors. We sterilize our surfaces. Their immune systems then become hyper-sensitized.

You have these little soldier cells in your body called neutrophils. And those neutrophils, when they spend too long going around looking for something to do, they become grumpy and pro-inflammatory. And so when they finally see something that's foreign, like a piece of pollen¹⁵, they become explosively inflammatory. They go crazy, right? And that's what triggers asthma and eczema and oftentimes food allergies.

GARCIA-NAVARRO: So I was going to ask you just finally to give us some advice. I mean, as a mother, what should I be allowing my daughter to do? And what is still something that I should not allow her to do?

GILBERT: Right. So oftentimes, it's hard to get your kids to eat a healthy diet, right? I know this more than any parent. But I would strongly try and encourage the consumption of more colorful vegetables, more leafy vegetables, a diet more rich in fiber¹⁶, as well as reducing the sugar intake¹⁷. But just generally, allow your kid to experience the world. As long as they're properly vaccinated¹⁸, there's no threat. And they will actually get a stronger, more beneficial exposure.

GARCIA-NAVARRO: Dr. Jack Gilbert. He's the co-author of "Dirt Is Good." Thank you so very much.

GILBERT: Thank you. It's great to be here.

(SOUNDBITE OF PENGUIN CAFE ORCHESTRA'S "DIRT")

1 jack   

n.插座，千斤顶，男人；v.抬起，提醒，扛举；n.（Jake）杰克

参考例句：

• I am looking for the headphone jack.我正在找寻头戴式耳机插孔。
• He lifted the car with a jack to change the flat tyre.他用千斤顶把车顶起来换下瘪轮胎。

2 antibiotics   

n.（用作复数）抗生素；（用作单数）抗生物质的研究；抗生素，抗菌素( antibiotic的名词复数 )

参考例句：

• the discovery of antibiotics in the 20th century 20世纪抗生素的发现
• The doctor gave me a prescription for antibiotics. 医生给我开了抗生素。

3 sterilize   

vt.使不结果实；使绝育；使无效；杀菌，消毒

参考例句：

• Antiseptic is used to sterilize the skin before giving an injection.杀菌剂被用于在注射前给皮肤消毒。
• He pricks the blister on his heel with a sterilize needle.他用一根消过毒的针扎破他脚后跟上的水泡。

4 sterilized   

v.消毒( sterilize的过去式和过去分词 )；使无菌；使失去生育能力；使绝育

参考例句：

• My wife was sterilized after the birth of her fourth child. 我妻子生完第4个孩子后做了绝育手术。 来自辞典例句
• All surgical instruments must be sterilized before use. 所有的外科手术器械在使用之前，必须消毒。 来自辞典例句

5 delved   

v.深入探究，钻研( delve的过去式和过去分词 )

参考例句：

• She delved in her handbag for a pen. 她在手提包里翻找钢笔。
• He delved into the family archives looking for the facts. 他深入查考这个家族的家谱以寻找事实根据。 来自《简明英汉词典》

6 sterilizing   

v.消毒( sterilize的现在分词 )；使无菌；使失去生育能力；使绝育

参考例句：

• The nurse is sterilizing the surgical instruments. 护士在把外科手术器具消毒。 来自辞典例句
• By testing, steam is the ble sterilizing method for herbal medicine. 这些方法难以保证药性，或有残留，要不然就是费用昂贵。 来自互联网

7 filthy   

adj.卑劣的；恶劣的，肮脏的

参考例句：

• The whole river has been fouled up with filthy waste from factories.整条河都被工厂的污秽废物污染了。
• You really should throw out that filthy old sofa and get a new one.你真的应该扔掉那张肮脏的旧沙发，然后再去买张新的。

8 allergies   

n.[医]过敏症；[口]厌恶，反感；（对食物、花粉、虫咬等的）过敏症( allergy的名词复数 )；变态反应，变应性

参考例句：

• Food allergies can result in an enormous variety of different symptoms. 食物过敏会引发很多不同的症状。 来自辞典例句
• Let us, however, examine one of the most common allergies; hayfever. 现在让我们来看看最常见的变态反应的一种--枯草热。 来自辞典例句

9 asthma   

n.气喘病，哮喘病

参考例句：

• I think he's having an asthma attack.我想他现在是哮喘病发作了。
• Its presence in allergic asthma is well known.它在过敏性气喘中的存在是大家很熟悉的。

10 robust   

adj.强壮的，强健的，粗野的，需要体力的，浓的

参考例句：

• She is too tall and robust.她个子太高，身体太壮。
• China wants to keep growth robust to reduce poverty and avoid job losses,AP commented.美联社评论道，中国希望保持经济强势增长，以减少贫困和失业状况。

11 susceptible   

adj.过敏的，敏感的；易动感情的，易受感动的

参考例句：

• Children are more susceptible than adults.孩子比成人易受感动。
• We are all susceptible to advertising.我们都易受广告的影响。

12 premise   

n.前提；v.提论，预述

参考例句：

• Let me premise my argument with a bit of history.让我引述一些史实作为我立论的前提。
• We can deduce a conclusion from the premise.我们可以从这个前提推出结论。

13 fermented   

v.（使）发酵( ferment的过去式和过去分词 )；（使）激动；骚动；骚扰

参考例句：

• When wine is fermented, it gives off gas. 酒发酵时发出气泡。 来自《简明英汉词典》
• His speeches fermented trouble among the workers. 他的演讲在工人中引起骚动。 来自辞典例句

14 bacterial   

a.细菌的

参考例句：

• Bacterial reproduction is accelerated in weightless space. 在失重的空间，细菌繁殖加快了。
• Brain lesions can be caused by bacterial infections. 大脑损伤可能由细菌感染引起。

15 pollen   

n.[植]花粉

参考例句：

• Hummingbirds have discovered that nectar and pollen are very nutritious.蜂鸟发现花蜜和花粉是很有营养的。
• He developed an allergy to pollen.他对花粉过敏。

16 fiber   

n.纤维，纤维质

参考例句：

• The basic structural unit of yarn is the fiber.纤维是纱的基本结构单元。
• The material must be free of fiber clumps.这种材料必须无纤维块。

17 intake   

n.吸入，纳入；进气口，入口

参考例句：

• Reduce your salt intake.减少盐的摄入量。
• There was a horrified intake of breath from every child.所有的孩子都害怕地倒抽了一口凉气。

18 vaccinated   

[医]已接种的，种痘的，接种过疫菌的

参考例句：

• I was vaccinated against tetanus. 我接种了破伤风疫苗。
• Were you vaccinated against smallpox as a child? 你小时候打过天花疫苗吗？