自產農產品對健康的好處

Americans need to adopt a more plant-based diet, rich in fruits and vegetables, according to a recent report that proposed updates to federal dietary guidelines. And for good reason: Plants offer a host of health benefits. Aside from their fiber, vitamins, and minerals, evidence suggests that fruits and veggies contain compounds that play a role in preventing certain cancers as well as heart disease and stroke, for which supplements are no substitute, says dietitian Elizabeth Pivonka, president of the nonprofit Produce for Better Health Foundation.
美國人需要進行一個以更多植物爲主的飲食，富含水果和蔬菜，按照最近一個報道建議更新聯邦膳食指南。因爲有好的理由：植物提供有關健康的許多好處。除了它們所含有的纖維，維生素和礦物質，證據顯示水果和蔬菜中含有對預防一些癌症，心臟病和中風有用的化合物，這些是補充劑所不能代替的，營養學家，非營利性的更保健農產品基金會主席Elizabeth Pivonka說。

Beta carotene found in carrots and sweet potatoes, for example, has been shown to help protect against lung cancer, but may be harmful when taken in pill form. And the latest research suggests that calcium supplements may raise the risk of heart attacks in adults while doing little to benefit bone health. (That's why some researchers are now encouraging folks to get the nutrient in their diet instead. Spinach and broccoli are good sources.)
例如，胡蘿蔔和紅薯中的β-胡蘿蔔素，已經顯示可以幫助預防肺癌，但是如果以藥丸的形式吃下去就對身體有害了。最新的研究表明成人服用鈣補充劑會增加患心臟病的風險，而且對骨骼健康沒有好處。（這就是爲什麼如今一些研究人員鼓勵人們從飲食中獲取營養。菠菜和西蘭花就是很好的來源。）

Getting more isn't always easy. Supermarket produce can be expensive, making packaged snacks—already sweeter or saltier and higher in calories than fruits and vegetables—all the more tempting. A cheaper alternative: Grow your own. Home-grown produce has other advantages beyond its low cost. It's often tastier and arguably a bit more nutritious. Here's why:
獲取更多營養並不容易。超市產品很貴，使包裝的零食更加誘人，它們比水果蔬菜更甜或更鹹，而且含有更多熱量。一個更實惠的選擇：自己種植。自產產品除了價格低還有其他優勢。更加美味而且更有營養。下面是原因：

Those bright red bell peppers or crisp green beans at the supermarket are likely to have traveled many miles over several days before landing in your cart. Although both the vegetables are a good source of vitamin C—known for bolstering the immune system—a long journey from farm to table gives the nutrient ample opportunity to degrade, especially if exposed to heat. In fact, temperature is the most important factor in keeping harvested fruits and vegetables in good shape, says Diane Barrett, a food biochemist from the University of California, Davis, who helps teach best practices to locals who grow, ship, and distribute fresh produce. One would expect then that temperature is tightly controlled in transit, but in realty she says that does not always happen.
超市裏那些鮮紅的燈籠椒或新鮮的四季豆很有可能是經過幾天很多英里的運輸纔到達你的手推車的。儘管這兩種蔬菜都富含維生素C（可以增強免疫系統）但從農場到餐桌的長時間運輸使其中的營養物質大大流失了，尤其是接觸到高溫。實際上，溫度是保持摘收水果新鮮好看的最主要因素，加利福尼亞加州大學一個食品生物化學家Diane Barrett說，並幫助傳授給當地人種植，運送和分配新鮮產品的最佳方法。人們會認爲在運輸過程中會嚴格控制溫度，但她說實際上不一定。Complicating matters is that the optimal temperature differs from plant to plant, she says. Tomatoes, for example, should not be refrigerated and are generally best if stored between 50 and 55 degrees Fahrenheit. Despite the different needs of certain fruits and vegetables, they may be shipped together.
她說，麻煩的是植物的最佳溫度各不相同。例如，番茄必須冷藏，一般最佳冷藏溫度是50-55華氏溫度。即使不同水果和蔬菜需要不同溫度，但是它們還是一起裝船運輸。

In terms of taste, fresh is best. Supermarket tomatoes are frequently picked green before they have the chance to fully develop flavor, a technique that helps them withstand transport, says Raoul Adamchak, coordinator of the Market Garden at the UC Davis Student Farm. (Later, they are artificially ripened with ethylene.) Moreover, growers who ship their produce cross-country may favor certain varieties over others not for their taste, but because they travel well. Heirloom tomatoes, for example, are too delicate to be shipped and are often absent from store shelves.
從味道方面來說，新鮮是最美味的。超市裏的番茄通常在未熟，不能完全釋放它味道的情況下就摘了，這樣可以幫助它們抵抗運輸過程引起的營養流失，加州大學戴維斯分校商品菜園的協調者Raoul Adamchak說。（後來，他們用乙烯人工催熟。）另外，把農產品運送到世界各地的種植者會更喜歡某些種類，不是因爲它們的味道，而是因爲它們運輸得好。例如，祖傳番茄太脆弱而不能用船運送，所以商店貨架上常常缺乏。

For your own garden, relish the freedom to pick among the most flavorful varieties (more than 400 types of tomatoes exist). And don't neglect color: Compounds called phytochemicals provide protection for plants and may give humans some padding against aging. Lycopene and beta carotene are phytochemicals; anthocyanins are another kind. Found in blueberries and cranberries, anthocyanins have been shown to aid memory. Eating an array of colors, says Pivonka, will ensure you get an assortment of nutrients and protective phytochemicals.
在自己的花園裏，自由採摘品味最美味的種類（有超過400種番茄）。不要忽視顏色：一種叫做植物素的化合物給植物提供保護還補充幫助人類對抗衰老。番茄紅素和β-胡蘿蔔素都是植物素；花青素是另一種化合物。已經指出藍莓和蔓越橘中所含的花青素可以幫助記憶。Pivonka說，吃各種顏色的食物可以確保你獲取各種營養和有保護作用的植物素。

Still, home-grown produce may have only a slight nutritional advantage over the store-bought kind. What really matters, says Pivonka, is that you eat more. Half your plate should contain fruits or vegetables at every meal, she says.
但是，自產農產品比商店買的農產品只有一點點營養優勢。Pivonka說，真正重要的是你吃更多。她說，每餐都要有一半的菜是水果和蔬菜。