蔬果昔的是是非非（之二）

系列之2：蔬果昔对你有坏处吗？

请看 Michael Greger 医生制作的小视频：

https://v.qq.com/txp/iframe/player.html?vid=a1336qb3ll3&width=500&height=375&auto=0

蔬菜和水果是地球上营养密度最高的食物，而深绿色的蔬菜则是王中之王。

Fruits and vegetables are the most nutrient-dense foods on the planet, and dark green leafy vegetables lead the pack.

被称作“像发电厂一样的蔬菜和水果”中最有营养的前5名是绿叶蔬菜。

Each of the top five so-called “power house fruits and vegetables” were greens.

中国白菜（美国超市名字Bok Choy，跟汉语拚音 Bai Cai差不多）

（译者注：营养密度100分的绿叶蔬菜除 Watercress（西洋菜）外，还有另外三种：

Kale（羽衣甘蓝）

Collard Greens（芥蓝菜叶）

Mustard Greens（芥菜）

2017年3月16号 Joel Fuhrman 医生制作了最新ANDI食物评分表，感兴趣的可参考以下链接：

https://www.drfuhrman.com/library/eat-to-live-blog/128/andi-food-scores-rating-the-nutrient-density-of-foods ）

如果把这些蔬菜用搅拌机搅碎（或者做成汤或酱），搅拌破坏细胞壁使营养最大限度被释放出来，这些释放出来的营养物质就会快速进入血液。

And so, if we blend them up in a smoothie (or soup or sauce),we’re taking the food with the most nutrition and breaking all the cell walls to dump that nutrition into our blood stream.

从消化和营养吸收的的效率来看，咀嚼是好的，但搅拌的效果更好。

Chewing is good, but blending is better, in terms of digestive efficiency and absorbing nutrients.

如果我们（的消化道上段）快速吸收了营养，造成没有营养到达结肠，会不会使结肠内的菌群挨饿呢？

But if we suck up all that nutrition such that none of it makes it down to our colon, might we be starving our microbial selves?

完整的谷物、豆类和坚果比面包、鹰嘴豆泥和坚果泥好的原因是因为无论我们怎么咀嚼，完整的食物碎片会到达结肠，它们会提供“自助餐”给结肠内的益生菌。

The reason intact grains, beans, and nuts are better than bread, hummus, and nut butters is that no matter how well we chew, intact food particles make it down to your colon where they can offer a smorgasbord for your good bacteria.

图中箭头所指显示的是粪便中谷物被细菌消化后的侵蚀部分。

但如果谷物、豆类和坚果被搅拌的非常碎，即在你吃之前就成为面粉和泥状，可能会使你的肠道菌群缺乏食物。

But if your grains, beans, and nuts are finely ground up into flour or paste before you eat it, you may be leaving your gut flora high and dry.

对于蔬菜和水果也会是一样的吗？

Would the same be true for fruits and vegetables?

蔬菜和水果有特别种类的微量营养素会保护结肠免生癌症。蔬果昔逃过了胃和小肠的消化和吸收直接到达结肠，作用就像是益生菌一样。无论我们如何咀嚼，这些东西都与纤维附着在一起。

There are special classes of phytonutrients in fruits and vegetables that appear to protect against colon cancer. They can escape digestion and absorption in our stomach and small intestine, and end up in our colon to act as prebiotics. No matter how much we chew, they stay attached to the fiber.

上图：高达90%的植物多酚逃过了消化道上段的消化和吸收，直接到达结肠。在那里接触肠道微生物，作为肠道微生物的培养基，例如小的酚酸和SCFA，确实，对肠道微生物的种类和新陈代谢行为有一定影响。

但如果用搅拌机会不会让这些营养物质提前脱离出来呢?

But if we use a blender, might we prematurely detach these nutrients?

答案是：不会的。即使用最高速的搅拌机搅拌5分钟，这些营养物质还是附着在纤维上，一起被运送给结肠的细菌。

No. Even if you blend in a high-speed blender for five minutes, they remain bound to the fiber for transport down to your colon bacteria.

对有回肠造口袋的人取出小肠内容物进行蔬果昔试验结果显示，那些多酚植物营养素大部分都完好无损地可到达结肠。所以当搅拌蔬菜和水果时，不用担心抢劫一方去补另一方的问题。

You can do smoothie experiments on people with ileostomy bags that drain the contents of the small intestine, and show that most of the polyphenol phytonutrients make it out intact. So we don’t have to worry we may be robbing Peter to pay Paul when we blend fruits and vegetables.

图中比较原苹果昔中几种营养素含量与从回肠造口袋中取出物中营养素含量

那么蔬果昔有没有不好的一面呢？

Is there any downside to smoothies, then?

对于蔬果昔，只是因食物颗粒小会增加消化和吸收效率，对谷物或许也一样。但对谷物的顾虑则是搅拌会促使淀粉更容易消化和吸收而引起血糖波动。

Well, just as smaller particle size may improve digestive  efficiency and gastrointestinal absorption of nutrients from fruits and vegetables, the same may be true for grains. But the concern is that this could boost starch availability and cause a blood sugar spike.

例如：这是吃半杯糙米后4小时血糖的升高和下降，诱发胰岛素缓慢波动来应对血糖的变化。并没有超过禁食期血糖变化范围。 

For example, here’s the rise and fall in our blood sugar in the four hours after eating a half cup of brown rice, eliciting a nice gentle bump in our insulin levels to take care of it. Doesn’t even go above normal fasting blood sugar levels.

如果吃同样多的糙米，但吃糙米前先把糙米打成粉，再做成幼滑的糙米粥对血糖的影响会怎样呢？

But what if we ate the same amount of brown rice, but first ground into brown rice flour, so like a cream of brown rice hot cereal?

血糖和胰岛素的波动就会加倍。等量的食物，只是形式不同。这就是完整形式的全谷物比用粉状全谷物做的产品好的原因。

You get twice the blood sugar, twice the insulin spike. Same amount of food, just in a different form. Another reason why intact whole grains are better than whole grain flour products.

即使只是仔细咀嚼谷物也会增加血糖和胰岛素的反应。这就是普通咀嚼与仔细咀嚼的区别。

Even just chewing really well can boost the glycemic and insulin response. Here’s if you just chew rice regularly and here’s if you chew really well.

下面是正常咀嚼情况下血糖和胰岛素反应图：

下图中较高的曲线是仔细咀嚼情况下血糖和胰岛素反应图：

较小的糙米颗粒会缩短胃排空时间，造成较大的血糖和胰岛素反应。

The smaller rice particles empty out of your stomach faster, producing greater blood sugar and insulin responses.

讽刺的是，有位狂热的健康专家大力提倡仔细咀嚼食物以更好消化。但如果是仔细咀嚼含5种奶酪的披萨呢？也许咀嚼的不太仔细还更好。

It’s ironic that there were health crusaders pushing people to chew more to digest their food better, but if what you’re chewing is a five-cheese pizza, maybe it’s better not to digest so well.

下图中这位先生提倡咀嚼食物50 – 100次成为液体后再吞下：

下图：含5种奶酪的披萨仔细咀嚼后造成血糖波动大

有人还建议肥胖和糖尿病人不要咀嚼食物太多。不经过咀嚼地吞下切成块的食物，不仅会失去吃的乐趣，而且还可能会噎着。

Some have even suggested that diabetics and obese persons not chew their food so much. Swallowing diced food without chewing would not only reduce the pleasure of eating, though, but people could choke on it.

然而，他们建议有个简单可接受的方法可以让病人降低血糖的波动而不需做不可思议的事（囫囵吞），就是多吃高纤维食物，例如豆类，已证实可以使血糖波动平缓。

Still, though, they suggest it could be a simple way to allow patients to reduce their blood sugar levels without fundamentally altering their diets and may thus prove more acceptable than having to do the unthinkable — eat high fiber foods like beans, which have been shown to blunt blood sugar spikes.

甚至是打成糊的豆类，象鹰嘴豆泥之类的（也可降低血糖波动吗）？

Even blended beans, like hummus?

答案是肯定的，豆类跟谷物不一样，搅碎豆类不会影响血糖反应。

Yes, unlike grains, blending legumes does not affect their glycemic response.

所以又回到蔬果昔的问题了，水果是更像是谷类还是更像豆类？

So, circling back to the smoothie question, is fruit more like grains or more like beans?

如果用水果做蔬果昔，会不会有血糖波动太大的风险？

If you liquefy fruit in a blender to make a smoothie, do you risk spiking your blood sugar too high?

请听下回分解。

We’ll find out next.