美国国家公共电台 NPR You Don't Have To Go No-Carb: Instead, Think Slow Carb

 

STEVE INSKEEP, BYLINE¹: Some people who watch what they eat may be overlooking the most important things. Counting calories is a bit too simple. Cutting carbs is a bit too hard. So what can you do? NPR's Allison Aubrey has a different strategy.

ALLISON AUBREY, BYLINE: Have you ever stopped to think, what is a calorie? To find out, we're going to bring out a blowtorch.

MATT HARTINGS: If there's anything we chemists know how to do, it's burn things.

AUBREY: That's Matt Hartings. He's a chemistry professor, and we're in his lab at American University.

HARTINGS: What we're going to do is, we are going to burn our food. You ready?

AUBREY: We've got two different kinds of foods here. We've got a piece of white bread, and we've got a little handful of whole-grain wheat kernels³.

HARTINGS: So I've got my propane torch here that we're going to use to start this bread. The way it needs to be going.

AUBREY: All right. Let's do it.

Now we need to measure how much heat each piece of food is giving off. That's where the calorie count comes from.

HARTINGS: You see the smoke coming up from in there?

AUBREY: That's a lot of smoke.

HARTINGS: It is a lot of smoke. These things are reacting with oxygen, or burning, and we're measuring the amount of energy that comes off when they burn. Right? It's the same reaction that goes on in our bodies.

AUBREY: It turns out that the white bread we burned has about the same number of calories as the wheat kernels. But...

HARTINGS: How the calories themselves burn in our bodies is different from one food to the next.

AUBREY: And once you understand how this really works, it just may change the way you eat. For me, I realized that if I start the day with a pastry⁴ or a bagel, I'm hungry an hour later. But if I eat an egg, I'm good until lunch. It's got some fat and protein.

DAVID LUDWIG: We've known for decades, if not a century, that different foods affect the body differently, apart from their calorie content.

AUBREY: That's David Ludwig of Boston Children's Hospital. He's a physician who founded a weight loss clinic. Now, remember those whole grains we just burned? He says they've got a lot going for them.

LUDWIG: They take a while to digest, leading to a gentle rise of blood sugar and insulin after the meal.

AUBREY: And that's good. But the white bread, on the other hand, is more likely to lead to a spike⁵ and a crash in your blood sugar. That's because all the good stuff, like the fiber⁶ and the germ, have been processed out. All that's left is the starch⁷.

LUDWIG: According to one way of thinking, these processed carbohydrates⁸ raise blood sugar and insulin, and that directs calories more into storage in fat cells.

AUBREY: So eating a lot of refined carbohydrates can make us hungry, maybe put us on a path to weight gain and, over the long term, may increase the risk of Type 2 diabetes⁹. And it's not just white bread. Think of all of the snack foods we encounter every day, even here at the NPR headquarters.

OLIVER DEARDEN, BYLINE: The biggest cause of obesity¹⁰ in the United States is offices.

AUBREY: (Laughter).

That's Oliver Dearden. He works on All Things Considered, and he sits just a few feet away from one of the best free-food tables at NPR.

DEARDEN: Open bags of chips...

AUBREY: And some cookies left over from a meeting.

DEARDEN: People are like bees. They'll just come and just swarm¹¹ around it. It's gone.

AUBREY: And it's pretty clear that none of this stuff has any whole grain left in it. It's just a bunch of refined starch and sugar. So David Ludwig's advice is this.

LUDWIG: Just get off the roller coaster.

AUBREY: In other words, you want to try to cut way back on all those foods that just don't give your body much of what we need.

INSKEEP: Allison Aubrey, I've got a question. What about just going with no carbs, as some people try?

AUBREY: Hi there, Steve. If you try to give up all carbs, you're going to set yourself up to fail. I mean, think of fruit and beans. They are loaded with carbohydrates. But when you eat a piece of fruit, you're getting a lot of fiber. You're getting a lot of micronutrients. When you eat beans, it's a great source of protein. So you don't want to give up all carbs. Instead of going no-carb, why don't you go slow-carb?

And by that I mean you want carbs that digest slowly, like the whole grains we just heard about, the fruits and beans. You know, when you eat rice, opt¹³ for the brown rice instead of the refined white rice.

INSKEEP: I guess it's not too hard to avoid white bread. I could just buy wheat bread, or whatever. But on some level, are the bad carbs - if that's the right way to phrase it - are they just going to be very hard to avoid?

AUBREY: They're just sort of empty carbs, and they are hard to avoid. But you can just sort of change the way you shop. I mean, here's what I had for breakfast this morning. This is a three-grain bread, just sort of, like, traditional pumpernickel rye.

INSKEEP: OK. Thank you.

AUBREY: Have a little bite. Now, if you look at that, it's got the grain. It's still intact. Now, that's a sign that it's a whole grain.

INSKEEP: OK.

AUBREY: Here. I'm going to hand you this little wheat kernel² here.

INSKEEP: OK.

AUBREY: Now, if you were to pop that open, what you would find is a little germ. And I want you to think about that germ as a little packet of nutrients¹². It's got magnesium¹⁴. It's got zinc¹⁵. It's got potassium. All of that stuff is good for you. It's also got a ton of fiber.

But think about it. All that good stuff is stripped out of all of these refined snacks and breads we eat. Do you want to eat that way?

INSKEEP: No.

AUBREY: (Laughter). OK.

INSKEEP: But I'm going to eat this bread. It's pretty good. Thank you very much. Am I eating your breakfast?

AUBREY: You are just eating my leftovers¹⁶.

INSKEEP: OK. Fine. Fine. Do you have any advice for when you don't bring me breakfast, like you just did?

AUBREY: (Laughter). You know what? I'm going let you off the hook here. I'm going to say it's fine to eat those croissants or that baguette out there. Because you know what? It's completely unrealistic to think that these things are going to go away. Right? Like, I love a good croissant. I mean, I'm sure you do, too. I'm sure all of you out there do.

INSKEEP: They can go away when I eat them.

AUBREY: (Laughter) Right. But here's one thing to remember. If you want to eat those kind of things, eat them at the end of a meal. And here's why. The timing¹⁷ of when you eat these refined carbs really does seem to matter. In fact, there was this cool little study done a few years back. It found that compared to eating bread at the beginning of the meal, if you eat bread at the end of the meal, it actually lowered the peak blood sugar of people in the study by about 30 percent, which is big.

Now, this trick might not have the same effect on everyone, but it does suggest that the timing really matters. So think about bread as dessert.

INSKEEP: And lower blood sugar means I don't get kind of a sugar high, I don't crash later, I don't get hungry later?

AUBREY: Exactly. Short-term effect of that would be maybe you don't get hangry. Long-term effect of that is you cut the risk of Type 2 diabetes.

INSKEEP: OK. We want to mention that these tips are from Allison's latest episode of Life Kit¹⁸. What is that?

AUBREY: OK. Life Kit is our new family of audio guides to help you navigate¹⁹ your life, Steve. We've got one new one coming out today. It's on making smarter decisions when it comes to eating well.

INSKEEP: OK. So eat the bread at the end of the meal...

AUBREY: You got it.

INSKEEP: ...Listen to the podcast before the meal.

AUBREY: (Laughter). You're good.

INSKEEP: Allison, thanks so much.

AUBREY: Thanks, Steve.

INSKEEP: That's NPR's Allison Aubrey. And you can find Life Kit guides wherever you get podcasts or at npr.org/lifekit.

1 byline   

n.署名；v.署名

参考例句：

• His byline was absent as well.他的署名也不见了。
• We wish to thank the author of this article which carries no byline.我们要感谢这篇文章的那位没有署名的作者。

2 kernel   

n.(果实的)核，仁；(问题)的中心，核心

参考例句：

• The kernel of his problem is lack of money.他的问题的核心是缺钱。
• The nutshell includes the kernel.果壳裹住果仁。

3 kernels   

谷粒( kernel的名词复数 )； 仁； 核； 要点

参考例句：

• These stones contain kernels. 这些核中有仁。
• Resolving kernels and standard errors can also be computed for each block. 还可以计算每个块体的分辨核和标准误差。

4 pastry   

n.油酥面团，酥皮糕点

参考例句：

• The cook pricked a few holes in the pastry.厨师在馅饼上戳了几个洞。
• The pastry crust was always underdone.馅饼的壳皮常常烤得不透。

5 spike   

n.长钉，钉鞋；v.以大钉钉牢，使...失效

参考例句：

• The spike pierced the receipts and held them in order.那个钉子穿过那些收据并使之按顺序排列。
• They'll do anything to spike the guns of the opposition.他们会使出各种手段来挫败对手。

6 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。

7 starch   

n.淀粉；vt.给...上浆

参考例句：

• Corn starch is used as a thickener in stews.玉米淀粉在炖煮菜肴中被用作增稠剂。
• I think there's too much starch in their diet.我看是他们的饮食里淀粉太多了。

8 carbohydrates   

n.碳水化合物，糖类( carbohydrate的名词复数 )；淀粉质或糖类食物

参考例句：

• The plant uses the carbohydrates to make cellulose. 植物用碳水化合物制造纤维素。 来自《简明英汉词典》
• All carbohydrates originate from plants. 所有的碳水化合物均来自植物。 来自辞典例句

9 diabetes   

n.糖尿病

参考例句：

• In case of diabetes, physicians advise against the use of sugar.对于糖尿病患者，医生告诫他们不要吃糖。
• Diabetes is caused by a fault in the insulin production of the body.糖尿病是由体內胰岛素分泌失调引起的。

10 obesity   

n.肥胖，肥大

参考例句：

• One effect of overeating may be obesity.吃得过多能导致肥胖。
• Sugar and fat can more easily lead to obesity than some other foods.糖和脂肪比其他食物更容易导致肥胖。

11 swarm   

n.(昆虫)等一大群；vi.成群飞舞；蜂拥而入

参考例句：

• There is a swarm of bees in the tree.这树上有一窝蜜蜂。
• A swarm of ants are moving busily.一群蚂蚁正在忙碌地搬家。

12 nutrients   

n.（食品或化学品）营养物，营养品( nutrient的名词复数 )

参考例句：

• a lack of essential nutrients 基本营养的缺乏
• Nutrients are absorbed into the bloodstream. 营养素被吸收进血液。 来自《简明英汉词典》

13 opt   

vi.选择，决定做某事

参考例句：

• They opt for more holiday instead of more pay.他们选择了延长假期而不是增加工资。
• Will individual schools be given the right to opt out of the local school authority?各个学校可能有权选择退出地方教育局吗？

14 magnesium   

n.镁

参考例句：

• Magnesium is the nutrient element in plant growth.镁是植物生长的营养要素。
• The water contains high amounts of magnesium.这水含有大量的镁。

15 zinc   

n.锌；vt.在...上镀锌

参考例句：

• Brass is formed by the fusion of copper and zinc.黄铜是通过铜和锌的熔合而成的。
• Zinc is used to protect other metals from corrosion.锌被用来保护其他金属不受腐蚀。

16 leftovers   

n.剩余物，残留物，剩菜

参考例句：

• He can do miracles with a few kitchen leftovers.他能用厨房里几样剩饭做出一顿美餐。
• She made supper from leftovers she had thrown together.她用吃剩的食物拼凑成一顿晚饭。

17 timing   

n.时间安排，时间选择

参考例句：

• The timing of the meeting is not convenient.会议的时间安排不合适。
• The timing of our statement is very opportune.我们发表声明选择的时机很恰当。

18 kit   

n.用具包，成套工具；随身携带物

参考例句：

• The kit consisted of about twenty cosmetic items.整套工具包括大约20种化妆用品。
• The captain wants to inspect your kit.船长想检查你的行装。

19 navigate   

v.航行，飞行；导航，领航

参考例句：

• He was the first man to navigate the Atlantic by air.他是第一个飞越大西洋的人。
• Such boats can navigate on the Nile.这种船可以在尼罗河上航行。