It's one of the most recognizable expressions around: "An apple a day keeps the doctor away." But besides the fact that it rhymes, which makes it fun to say and easy to recall, does it really have any value? Could the common apple honestly help a person to maintain perfect health?

    The first printed mention of this saying can be found in the February 1866 issue of the publication "Notes and Queries." The publication printed the proverb like this: "Eat an apple on going to bed, and you'll keep the doctor from earning his bread." Nearly 150 years later, variations of this adage are still quoted. It's unlikely that the saying would have maintained such popularity if there wasn't some truth to it, right? With that in mind, let's consider some of the apple's components and their effect on our health:

    *Pectin -- Pectin is a form of soluble fiber than lowers both blood pressure and glucose levels. It can also lower the levels of LDL, or "bad" cholesterol in the body. Pectin, like other forms of fiber, helps maintain the health of the digestive system. Apples are an excellent source of pectin.

    *Boron -- A nutrient found in abundance in apples, boron supports strong bones and a healthy brain.

    *Quercetin -- A flavonoid, this nutrient shows promise for reducing the risk of various cancers, including cancers in the lungs and breast. It may also reduce free radical damage. Free radicals develop when atoms in the body's cells have unpaired electrons, which can lead to damage to different parts of the cell, including DNA. Quercetin may neutralize free radical damage, which has been implicated in a variety of age-related health problems, including Alzheimer's disease.

    *Vitamin C -- Vitamin C boosts immunity, which helps maintain overall health.

    *Phytonutrients -- Apples are rich in a variety of phytonutrients, including vitamins A and E and beta carotene. These compounds fight damage from free radicals and can have a profound affect on health, including reducing the risk of heart disease, diabetes and asthma.

    Apples also act as a toothbrush, cleaning teeth and killing bacteria in the mouth, which may reduce the risk of tooth decay. They're also low in calorie density, one of the trademarks of a healthy food. When a food is low in calorie density you can eat good size portions of the food for relatively few calories. In addition, apples are affordable and readily available.

    With all of this information, it's easy to see that, yes, an apple has its health benefits. But does eating an apple every day mean you'll never get sick? And is an apple really healthier than other fruits? Find out on the following page.

    "一天一個蘋果醫生不來找我"這是人人皆知的順口溜之一。但事實上它只是童謠而已，便于好說好記，它真的有什么價值嗎？一個再普通不過的蘋果真的能幫助人保持完美健康？

    出版刊物"備忘和查詢"（Notes and Queries）1866年2月號中首先發現有對它的敘述。出版刊物中有諺語："睡前吃一個蘋果，醫生就會丟飯碗。"差不多在150年之后，這個變化了的諺語一直被引用。如果說的沒有一點事實，它也不可能一直被傳說和流行。它讓我們考慮蘋果的成分及其對我們健康的作用：

    果膠--果膠是一種可溶纖維能降低血壓和葡萄糖水平。它還能降低身體LDL（低密度脂蛋白）或"壞"的膽固醇水平，像其它纖維素一樣，能幫助消化系統維持健康狀態。蘋果是果膠的極好來源。

    硼--在蘋果中發現的一種豐富營養素，硼能壯骨和健腦。

    槲黃素--一種類黃酮，這種營養素表明能降低包括肺癌和乳腺癌在內的各種癌癥的危險。它還能減輕自由基破壞。自由基發生是當身體細胞中的原子有單電子，能導致包括DNA在內的細胞不同部分的破壞。槲黃素能中和自由基損害，包括老年癡呆癥在內的各種老化相關的健康問題。

    維生素C--維生素C能提高免疫性，幫助維護整體健康。

    植物營養素--蘋果含有豐富的包括維生素A 和 E在內的各種植物營養素及貝它胡蘿卜素。這些成分可以戰勝自由基破壞并對健康有深奧影響，涉及減少心臟病、糖尿病和哮喘的危險。

    蘋果還有牙刷作用，潔齒和殺滅口腔細菌，減少齲齒的危險。它們還能降低卡路里，這是保健食品的商標標志之一。當食品卡路里低，你就能吃相對低卡路里的大量食物。另外蘋果還是廉價和容易得到的。

    顯而易見所有這些信息，是說蘋果具有健康效益。但每天吃一個蘋果就意味著絕不會再有危險了？吃一個蘋果真的就比其它水果更健康？