您现在的位置: 纽约时报中英文网 >> 华尔街日报中英文版 >> 医疗 >> 正文

嚼口香糖对身体有害吗?

更新时间:2014-1-23 13:51:11 来源:华尔街日报中文网 作者:佚名

Is Chewing Gum Bad For You?
嚼口香糖对身体有害吗?

People have been chewing gum since the ancient Greeks peeled bark from mastic trees and used it as a breath sweetener. Today, the sticky stuff is consumed for so many more reasons -- to try to stave off hunger, deliver nicotine or simply provide diversion. But is smacking on a wad of gum actually harmful to the body? J. Sumner Bell, secretary-treasurer of the American Gastroenterological Association, offers an opinion.

The Brain Game

The moment a person unwraps a piece of gum and tosses it into his mouth, the brain is alerted that the digestive process is about to begin. During what's called the cephalic stage, the body anticipates oncoming food and releases saliva to help masticate the substance, then gastric, pancreatic and biliary fluids surge to further break it down. Because no real substance is ever delivered, some argue that gum-chewing can trick the system, upsetting the stomach by throwing off its acidity.

There is another way in which chewing gum might lead to tummy trouble. 'The salivary glands produce a bicarbonate-rich fluid, which would likely buffer some of the gastric acid,' notes Dr. Bell, who is a gastroenterologist in private practice in Virginia Beach, Va. 'The bloating, gas and discomfort occasionally reported after chewing gum throughout the day is more likely from air intake, not acid.'

Dr. Bell says he has patients who chew gum to help soothe acid reflux, though he doesn't generally recommend it. 'If the gum is flavored with peppermint, that can relax the esophageal sphincter, which may promote reflux,' he says.

Swallowing gum doesn't cause cramping and reflux, because there are minor peaks of gastric, pancreatic and biliary secretion in the periods between meals, when intestinal housekeeping takes place, Dr. Bell says. 'During that time, any gum would get swept up and flushed out. That process takes hours, not the mythical seven years.'

Sugar vs. Sorbitol

Doctors often advise patients to avoid sugary gum, because it can pull out tooth fillings and lead to cavities. But sugar-free gum has drawbacks, too, says Dr. Bell. Sorbitol, which also can be used to give gum sweetness, is a non-absorbable carbohydrate that in large doses can lead to GI problems.

A good analogy is lactose intolerance, says Dr. Bell: In a person lacking the small-intestinal enzyme that breaks down lactose, it will tumble through the intestines until it meets bacteria, which will ferment the sugar, releasing volatile gasses that can cause cramps, gas and even diarrhea.

'Sorbitol works the same way. There is individual tolerance, but if I have a patient who is having a difficult time with excessive gas, I will ask to look in her purse,' he says. 'Every now and then I'll find it full of gum.'

Hunger Games

Studies haven't successfully proven that gum can stave off hunger and lead to weight loss -- despite various gum-industry claims. In some people, the perceived sensation of satiety associated with gum-chewing may hold them over until meal time. But because chewing gum jump-starts the digestive process, it may in fact increase hunger. Just like seeing, smelling or tasting food, chewing gum 'can stimulate the secretion of salivary and gastric juices and may increase hunger as we anticipate food,' Dr. Bell says.

People with mild jaw issues often complain that gum-smacking exacerbates the clicking and discomfort of even mild temporomandibular joint disorder, or TMD, which can cause tightness of the jaw muscles. New studies have linked the chewing of any type of gum with migraine headaches in adolescents.

Researchers, however, have found a benefit: Recent studies have shown that chewing gum during a task can increase cognitive function. 'When I play golf, I find that chewing gum helps me concentrate and play a little bit better,' Dr. Bell says. 'Part of my pre-golf routine is to see that I have a pack of sugar-free gum in my bag -- though my wife thinks I'm reading too much into this.'

When to Chew

For those who really want to chew, Dr. Bell recommends trying sugarless gum after a meal. The saliva it helps to produce will clean the teeth, and the minty or fruity flavor will sweeten the breath and possibly satisfy a sweet tooth, Dr. Bell says. But it won't do much to advance digestion. 'There is no evidence that I know of that proves that chewing gum helps the digestive process,' Dr. Bell says.

人类从古希腊时期就开始嚼口香糖了,当时人们会剥取乳香树的树皮作为口气清新剂。如今,人们之所以吃这种黏黏的东西还有许多其他原因——消除 饿感,摄入尼古丁或者就是作为消遣。但有人说嚼口香糖其实对身体有害,这是真的吗?以下是美国胃肠病协会(American Gastroenterological Association)秘书-司库、弗吉尼亚州弗吉尼亚比奇(Virginia Beach)私人执业的胃肠病医生J·萨姆纳·贝尔(J. Sumner Bell)的观点。

口香糖会引起胃部不适吗?

当我们剥开一块口香糖,并把糖扔进嘴里时,会提醒大脑消化过程即将开始。在被称为“头期”的阶段,人体会预料到将有食物摄入,并释放唾液来辅助食物咀嚼,随后,胃酸、胰液及胆汁分泌会大幅增加,使食物进一步分解。一些人认为,由于没有真正的食物摄入,嚼口香糖会欺骗消化系统,刺激胃部分泌胃酸,导致胃部不适。

嚼口香糖可能引起胃部不适还有另外一个原因。弗吉尼亚州弗吉尼亚比奇(Virginia Beach)私人执业的胃肠病医生贝尔指出:“唾液腺产生一种富含碳酸氢盐的液体,这种液体或能中和部分胃酸。有时在嚼一整天口香糖后出现的腹胀、放屁和不适可能更多要归因于吸入的空气,而不是胃酸。”

贝尔医生称,他有一些病人通过嚼口香糖来缓解胃酸反流,不过他一般不推荐这种做法。他说:“如果口香糖是薄荷味的,会使食道括约肌放松,可能加重反酸。”

贝尔医生说,把口香糖吞下去不会导致绞痛和反酸,因为两餐之间会出现胃酸、胰液和胆汁分泌的小高峰,期间肠道会进行清扫。他说:“在这期间,任何口香糖能够都会被扫掉、冲走。这一过程会持续几个小时,并不是传说的七年。”

糖VS山梨糖醇

医生通常建议患者不要吃含糖口香糖,因为这会导致牙齿填充物脱落,引起龋洞。但贝尔医生说,无糖口香糖也有缺点。可作口香糖甜味剂的山梨糖醇是一种人体无法吸收的碳水化合物,大量摄入也会引起血糖波动。

贝尔医生说,一个贴切的类比是乳糖不耐受:如果一个人体内缺乏可分解乳糖的小肠?,乳糖就会一直停留在肠道内,直到遇到细菌为止,细菌会让乳糖发酵,释放出气体,引起绞痛、胀气甚至腹泻。
他说:“山梨糖醇的作用机制也是一样。山梨糖醇存在个体耐受性问题,但如果我有病人因胀气而不适,我会要求看看她的包。有时我会发现包里装满了口香糖。”

口香糖能抑制 饿吗?

并没有什么研究成功地证明口香糖能抑制 饿并有助于减轻体重——尽管口香糖行业有种种相关说法。对一些人来说,这种由咀嚼口香糖带来的饱腹感可能会让他们等到饭点再吃东西。但由于嚼口香糖会启动消化进程, 饿感其实有可能会加重。贝尔医生称,与看、闻或品尝食物一样,嚼口香糖“能刺激唾液和胃酸分泌,并有可能加重 饿感,因为我们期待食物的摄入”。

下颌有轻度问题的人常常抱怨,嚼口香糖会加重轻度颞下颌关节紊乱症的关节弹响症状和不适感。颞下颌关节紊乱症会导致下颌肌肉紧张。新的研究已发现,咀嚼各类口香糖都与青少年偏头痛有关联。

但研究人员发现嚼口香糖有一个好处:近期的研究显示,在处理任务时咀嚼口香糖能够提高认知功能。贝尔医生称:“当我打高尔夫球时,我发现嚼口香糖有助于集中精力,能稍稍提高我的成绩。我打高尔夫球之前的例行公事是看看包里有没有一包无糖口香糖——不过我妻子认为我太牵强附会了。”

什么时候嚼口香糖最好?

如果你真想嚼口香糖的话,贝尔医生的建议是试试在餐后吃无糖口香糖。贝尔医生说,口香糖会促进唾液分泌,能清洁牙齿,而薄荷或水果味口香糖能让口气清新,或许还能满足吃甜食的欲望。但嚼口香糖对促进消化没有什么帮助。贝尔医生说:“据我所知,没有任何证据显示嚼口香糖对消化过程有帮助。”

本文版权归道琼斯公司所有,未经许可不得翻译或转载。

相关文章列表