这种易长胖、巨升糖的粗粮，很多人天天吃！

玉米口感软糯、鲜甜，是很多人爱吃的粗粮，不少人的食谱里，早餐、午饭、晚饭都有它。但其实，玉米是所有粗粮里最会骗人的一种。

Corn, with its soft, waxy and sweet taste, is a kind of coarse cereal grain many people love to eat. For many, it is included in all three meals of the day: breakfast, lunch and dinner. But in fact, corn is the most deceptive of all coarse cereal grains.

图源：视觉中国

经测算，一根250克（半斤）的花糯玉米，热量高达400千卡，顶得上满满一盒外卖的米饭，如果换成家里的碗，相当于两碗米饭。

01 不同品种玉米热量相差近1倍

专家表示，玉米热量的高低其实要看品种，选错品种，不仅不利于减肥，还可能让一些人的血糖飙升。

Experts point out that the calorie content of corn actually depends on the variety. Choosing the wrong type may not only hinder weight loss efforts but could also cause blood sugar levels to spike for some individuals.

图源：视觉中国

根据测算结果，同样大小的玉米（按250克可食用部分计），黄糯玉米比甜玉米的热量整整高出了200千卡，相当于多吃了一碗多白米饭。（米饭按150克/碗=174千卡计算）

According to calculations, for similarly sized ears of corn (based on a 250-gram edible portion), yellow waxy corn contains a full 200 kcal more than sweet corn—equivalent to eating over an extra bowl of white rice (based on 150 grams per bowl = 174 kcal).

都是玉米，差距咋会那么大？

这其实和不同玉米品种里的淀粉、糖、脂肪含量差距巨大有关。如果按市售常见的品类，简单可分为糯玉米、甜糯玉米和甜玉米三大类。

糯玉米的含水量通常比甜玉米低，意味着它的“干货”更多。在这些干货中，碳水总量平均比甜玉米高10%，有的甚至超过30%，脂肪也高2%左右，综合起来让糯玉米的热量比甜玉米高出一大截。

Waxy corn typically has a lower water content than sweet corn, meaning it contains more "solid content". Among these solids, the total carbohydrates are on average 10 percent higher than in sweet corn, with some varieties even exceeding 30 percent. Additionally, the fat content is about 2 percent higher. Combined, these factors contribute to waxy corn having a significantly higher calorie content than sweet corn.

不少减脂人原以为2根玉米一顿晚饭刚刚好，实际上相当于吃了三四碗饭，热量比正常吃晚餐还高。

如果按女性一天1800千卡（不减肥）来算，纯吃花糯玉米，一天最多能吃4到5根。如果减肥需要控制热量到1500千卡，每餐不吃别的，只吃1根花糯玉米，这一天也吃不了太多别的了。

02 玉米可能是升糖炸弹

除了热量不低，一些品种的玉米升糖指数也不低。

有些玉米品种对血糖相对友好，比如甜玉米，GI值（升糖指数）在55左右，属于低GI食物。

但我国糯玉米的培育更多，市面上更常见的也是糯玉米或甜糯玉米。糯玉米属于中高GI（升糖指数）高GL（血糖负荷）主食，GI值在80至90以上。

Certain varieties of corn, such as sweet corn, are relatively more blood sugar-friendly, with a GI (glycemic index) of around 55, classifying it as a low-GI food. However, in China, waxy corn is more commonly cultivated, and it—or sweet-waxy hybrids—are more frequently found in the market. Waxy corn is a staple with a medium to high GI (glycemic index) and high GL (glycemic load), with a GI value ranging from 80 to over 90.

甚至有些品种，比米饭GI值还高，属于高GI食物。比如，有检测机构测得黑糯玉米的GI值高达106，比干吃葡萄糖升得还快，而馒头的GI值为85，糯米饭GI值为87。

糯玉米GI值为啥高？这和淀粉成分有关。

普通玉米是直链淀粉和支链淀粉的结合，而中国特有培育的糯玉米几乎全是支链淀粉（95%以上），进入身体后会更快地被分解消化。

03 玉米偶尔吃就好，还要控量

有人认为，玉米属于粗粮，只要控好热量，可以每天吃。但玉米有个缺点：所含的烟酸（B族维生素的一种）是结合型，不易被人体利用。

玉米虽是粗粮，但真不推荐天天只吃它。

健康的粗杂粮，不仅要粗更要杂，一定要搭配其它主食一起吃，才最稳妥。比如，钾和膳食纤维更丰富的红薯，维生素B族、烟酸更丰富的糙米，蛋白质质量更佳的燕麦、藜麦等。

To ensure a healthy intake of coarse cereals, it is essential not only to choose unrefined options but also to prioritize variety. The safest approach is to combine them with other staple foods. For example, pair them with potassium- and dietary fiber-rich sweet potatoes, brown rice which is abundant in B vitamins and niacin, or oats and quinoa known for their higher-quality protein.

喜欢吃玉米的朋友，也不用焦虑。如果正在减肥或控糖，可以选甜玉米（水果玉米），热量更低，升糖更友好。要注意控量，还要和蔬菜蛋白质搭配着吃。

如果想把玉米作为一种粗粮，丰富主食，一周偶尔安排吃几次就好，切勿天天吃，可以和杂粮饭、燕麦等搭配着吃。

此外，吃玉米时，要啃得干净些，因为玉米胚是营养素最富集的部分。

赶紧把这篇分享给你身边爱吃玉米的朋友吧，别再被玉米“背刺”啦！

编辑：李涵萌

实习生：杨佳润

来源：央视新闻 丁香医生

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