西瓜有多好 你可能不知道

Question:

问：

Is watermelon good for you? How much?

西瓜对人体有好处吗？有多大好处？

Answer:

答：

Watermelon is rich in nutrients – including vitamins A and C, B vitamins and potassium — but where it really packs a punch is with lycopene, the antioxidant pigment that gives the fruit its deep Red color. Some studies suggest that lycopene may have cardiovascular benefits, including reducing the risk of stroke, and eating watermelon may slightly lower blood pressure. Researchers have also looked at lycopene’s possible role in protecting against various cancers, though evidence is scant.

西瓜营养丰富，包括维生素A、维生素C、B族维生素和钾，但西瓜最有用的成分是番茄红素，即让西瓜呈现出深红色的那种抗氧化剂色素。一些研究表明，番茄红素可能有益于心血管健康，包括降低中风风险，并且吃西瓜可能会轻微降低血压。研究人员还对番茄红素在预防各类癌症上可能起的作用进行了研究，不过证据不足。

You can get lycopene from tomatoes, particularly cooked and stewed tomatoes, but “on a fresh basis, you can’t do better than watermelon,” said Penelope Perkins-Veazie, a professor at North Carolina State University in Raleigh who has studied lycopene and is an unpaid science adviser to the National Watermelon Promotion Board. Red watermelon has more lycopene than other watermelon varieties, and “seedless watermelon tends to have more,” she said.

人们可从番茄，尤其是经过烹制的熟番茄中吸收番茄红素，但“在新鲜的情况下，西瓜是最好的，”在位于罗利的北卡罗来纳州立大学(North Carolina State University)研究番茄红素的教授佩内洛普·珀金斯-维齐(Penelope Perkins-Veazie)说，她同时还是全国西瓜促进委员会(National Watermelon Promotion Board)的无薪科学顾问。她表示，红色西瓜中的番茄红素比其他品种的西瓜多，且“无籽西瓜中的番茄红素往往更多”。

Lycopene from watermelon is also easily absorbed into the body. In one small study, researchers gave volunteers lycopene from tomato juice and lycopene from watermelon; the tomato juice had received heat treatments to boost absorption. They found the two groups had similar blood levels of lycopene.

西瓜中的番茄红素易被人体吸收。在一项小型研究中，研究人员向志愿者提供了番茄汁中的番茄红素和西瓜中的番茄红素。为了促进吸收，番茄汁经过了加热。研究人员发现，两组人的血液中的番茄红素含量相近。

Though watermelon doesn’t have as much fiber as many other fruits and vegetables, it is fat-free, contains a lot of water and is low in calories, with about 45 calories in a one-cup serving.

尽管西瓜的纤维含量不及其他很多水果和蔬菜，但它不含脂肪，水分丰富，热量低，一杯份西瓜中所含的热量仅为45卡路里左右。

Many people worry about the amount of sugar in watermelon, but “that’s a bit of a misconception, because the sugar content is actually lower than some other fruits, gram for gram,” said Jennifer McDaniel, a registered dietitian and spokeswoman for the Academy of Nutrition and Dietetics. While a cup of diced watermelon has about nine grams of sugar, a medium banana contains 14 to 15 grams of sugar, as does a cup of blueberries. Dietary guidelines recommend adults eat two cups of fruit a day.

很多人担心西瓜的含糖量，但注册营养师、营养与饮食学会(Academy of Nutrition and Dietetics)发言人珍妮弗·麦克丹尼尔(Jennifer McDaniel)表示，“这里有一些误解，因为同等重量的话，西瓜的含糖量其实比其他一些水果还低。”一杯切成丁的西瓜所含的糖分约为9克，而一根中等大小的香蕉的含糖量为14到15克，和一杯蓝莓相当。一些膳食指南建议成年人一天吃两杯水果。

And while watermelon has a high glycemic index, a measure of a food’s ability to raise blood sugar levels, that also adds to the confusion. In fact, its high water content gives it a low glycemic load, meaning it does not raise blood sugar levels quickly in amounts typically eaten.

西瓜的血糖生成指数高——这是一个衡量食物提高血糖水平的能力的指标，这也进一步增加了人们的困惑。实际上，高含水量使西瓜的生糖负荷降低，也就是说按照常规的量食用西瓜不会导致血糖水平迅速升高。