時差N小時:口臭是如何引起的?

Morning breath is a topic of many jokes, and a realboon to the mouth wash and toothpaste industries.But what exactly causes the foul taste and odor inyour mouth when you wake up in the morning? Themost basic answer to this question is gravity.

早晨醒來后的口氣既是一個笑柄，又是許多漱口水和牙膏企業(yè)的福音。但究竟是什么讓你在一覺醒來之后，嘴里充滿了難聞又討厭的味道呢?這一問題的實質(zhì)卻在于地球引力。

If you've eaten fewer than three hours before you go to sleep, your stomach hasn't had time todigest all of your food. When you lie down, gravity causes the gastric juices that are busydigesting your food to come up into your throat. Because your airway and food pipe are side-by-side, they share an adjoining wall. Those gastric juices that have backed up in your food pipeactually permeate that wall and enter into your air pipe. These juices can irritate your larynx,and cause your voice to be hoarse and your breath to turn foul.

如果你吃了東西后不到三小時就上床睡覺了，那么你的胃就沒有時間來消化所有的食物。當(dāng)你躺下后，正在消化食物的胃液在引力作用下涌向你的喉嚨。由于你的氣管和食道是并排的，它們之間只有一層隔膜，所以當(dāng)胃液流回食道時，實際上有部分胃液通過隔膜，滲透進(jìn)了氣管。正是這些胃液使你感到喉嚨不適，并讓你的聲音變得沙啞，口氣變臭。

In addition, gastric juices are acidic enough to burn the mucous membranes in your throat,resulting in a sore throat that occurs in the mornings, but lessens throughout the day. Morningmouth tends to worsen with age, because as you get older, the top of your esophagus, thethin tube that leads from the mouth to the stomach, loosens. With the softening of the top ofthis tube, gastric juices can more easily escape from the esophagus into the air pipe.

此外，胃液的酸性太強(qiáng)足以傷害到你的喉嚨粘膜，導(dǎo)致早起時喉嚨疼痛，不過一天下來這種疼痛會減輕。隨著年齡的增長，早起時的口氣會越來越重，這是因為隨著年齡增大，你的食道頂部(也就是連接你的口腔和胃部的薄管)會變得越來越松。隨著食道頂部越來越寬，胃液從食道進(jìn)入氣管也變得更容易了。

Another contributing factor to morning breath is infrequent swallowing during sleep.Swallowing allows us to keep our mouth relatively free from odor-producing bacteria. Butwhen we're asleep, these bacteria can thrive, contributing to the bad taste in our mouthwhen we wake up.

另一個造成早晨口氣的重要原因就是在睡覺的時候偶爾咽唾液。吞咽使我們的口腔能夠相對減少口臭引起的細(xì)菌。然而當(dāng)我們睡熟時，這些細(xì)菌就會大量繁殖，因此我們醒來后的口氣非常的難聞。