活了大几十年，竟然不知道这些有关身体的惊人事实 - 再活一甲子

大自然创造了许多奇妙的东西，但很少有比人体更神奇的了。从勤奋的心脏到令人难以置信的大脑，我们的体内有很多复杂的器官，它们的功能甚至更复杂。一起看看吧。

Nature has produced many wondrous things but few are more amazing than the human body. From a hard-working heart to the incredible brain, there are complex organs in our bodies that perform even more complicated functions. Take a look.

人体内最勤奋的器官之一；它在人的平均寿命中约跳动 25 亿次，泵出 100 万桶血液。欧洲公共医学中心的一项研究显示，脉搏甚至会根据你听到的音乐而改变。

One of the hardest working organs in the body; it beats around 2.5 billion times and pumps a million barrels of blood during an average lifetime. The pulse even changes according to the music you listen to, according to a study by Europe PubMed Central.

大脑

大脑是人体内最复杂的器官，拥有数十亿个神经细胞，来自大脑的信息以近 322 千米/小时（200 英里/小时）的速度沿运动神经元传递。神经元没有痛觉感受器，这就是外科医生可以在患者清醒且头皮麻木时进行开颅手术的原因，如 BrainLine 上发表的一篇文章所述。

With billions of nerve cells, it is the most complex organ in the body and messages from the brain travel along the motor neurons at almost 200 mph (322 km/h). Neurons do not have pain receptors, which is why surgeons can perform open-brain procedures while a patient is awake and the scalp is numbed, as noted in an article posted on BrainLine.

皮肤

皮肤是人体最大的器官，根据 KidsHealth 上的一篇文章，皮肤会不断地自我更新，每分钟脱落 30,000 到 40,000 个死皮细胞。成人的皮肤重约 3.6 千克（8 磅），表面积约 2 平方米（22 平方英尺）。脚上的皮肤最厚（超过 4 毫米），眼睑的皮肤最薄（0.5 毫米）。

The human body’s largest organ is constantly renewing itself, shedding 30,000 to 40,000 dead skin cells every minute, as per an article on KidsHealth. An adult’s skin weighs about eight pounds (3.6 kilograms) and has a surface area of about 22 square feet (two square meters). The thickest skin is on your feet (over four mm) and the thinnest on your eyelids (0.5 mm).

婴儿在出生时有超过 300 块骨骼，但随着时间的推移，一些骨骼融合在一起，成年后骨骼数量为 206 块。一位成人的脚上有 26 块骨骼，而手上（包括手腕）包含 54 块骨骼。

A baby is born with over 300 bones but over time some fuse together, resulting in an adult bone count of 206. In an adult, 26 bones are in the feet whereas the hand, including the wrist, contains 54 bones.

你一定听说过人的耳朵和鼻子在不停地生长。事实是，由于重力的作用，它们确实会随着年龄的增长而变大，重力会使它们下沉并变大。洛克菲勒大学研究人员使用不同气味组合进行的一项研究显示，无论大小，鼻子都能识别出万亿种不同的气味。

You must have heard that one’s ears and nose never stop growing. The fact is they do get bigger with age due to gravity, which causes them to sag and become larger. Big or small, a nose can recognize a trillion different scents, according to a study conducted by researchers at The Rockefeller University using different combinations of odorants.

嘴

NCBI 的一篇文章显示，嘴里有超过 60 亿个细菌；一些是有益于口腔健康的有益微生物，而另一些则是可能导致牙齿和牙龈问题的致病菌。此外，正常人每天产生大约一到两升的唾液，一生中产生的唾液足以填满两个游泳池。

An NCBI article shows that there are over six billion bacteria in a mouth; some are good microbes that help your oral health, while others are pathogenic that can lead to tooth and gum problems. Also, an average person produces about one to two liters of saliva a day, enough to fill two swimming pools in a lifetime.

舌头

嘴里包含大约 10,000 个味蕾，其中大部分位于舌头上。然而，嗅觉对于辨别味道也是必不可少的，因此如果你感冒了，食物的味道就会变淡，因为感冒会妨碍你的嗅觉。NCBI 上发布的一项研究显示，就像指纹一样，每个人都有独特的舌印，只是在颜色、形状和表面特征上略有不同。

The mouth contains almost 10,000 taste buds, and most are situated on the tongue. However, the sense of smell is necessary for identifying taste, too, hence food can taste bland if you have cold, which hampers you sense of smell. And just like fingerprints, every person has a unique tongue print, with minor variations in color, shape and surface features, shows a study posted on NCBI.

下颌

根据重量，人体最强壮的肌肉是咬肌，也称为下颌肌。下颌肌能以 25 千克（55 磅）的力量闭合门牙，或以 90.7 千克（200 磅）的力量闭合臼齿，如“Guyton and Hall Textbook of Medical Physiology”中所述。

The strongest muscle, based on its weight, is the masseter muscle, also called the jaw muscle. Together, jaw muscles can close the teeth with a force as strong as 55 pounds (25 kilograms) on the incisor teeth or 200 pounds (90.7 kilograms) on the molar teeth, as explained in "Guyton and Hall Textbook of Medical Physiology."

静脉和动脉

富兰克林学院的研究表明，如果将所有动脉、静脉和毛细血管首尾相连，孩子的总长度约为 96,560 千米（60,000 公里），而成人的长度为 161,000 千米（100,000 公里）。足以绕地球几圈！

If all arteries, veins and capillaries were placed end to end, they would measure about 60,000 miles (96,560 km) for a child and 100,000 miles (161,000 km) for an adult, as per The Franklin Institute. That’s enough to stretch multiple times around the planet!

人脸上带有螨虫。你永远不会看到它们，但它们存在于你脸上的毛孔、毛囊和睫毛中。BBC.com 上的一篇文章指出，它们是八足微型螨虫，几乎完全无害。

Human beings carry mites on their faces. You will never see them but they reside in the pores of your face, hair follicles and eyelashes. They are eight-legged microscopic mites, which are almost entirely harmless, an article on BBC.com suggests.

头发每月平均增长 1.2 厘米（0.5 英寸），寿命为 2 至 7 年。根据一篇 NCBI 文章所述，每个毛囊都是独立的，并且有自己的生命周期，这就是所有头发不会同时生长或脱落的原因。

Your hair grows at an average of 0.5 inch (1.2 cm) each month and has a lifespan of two to seven years. Each hair follicle is independent and has its own life cycle, according to an NCBI article, which is why all hair don’t grow or fall at the same time.

根据美国眼科学会的一篇文章所述，科学家估计一只眼睛能过分辨出多达 1,000 万种颜色。睫毛的寿命约为五个月，如果将人类在一生中脱落的睫毛放在一起，总长度可达近 30.5 米（100 英尺）。

According to an American Academy of Ophthalmology article, scientists estimate that an eye has the ability to distinguish up to 10 million colors. The eyelashes have a life span of about five months, and the total length of lashes shed by a human being during a lifetime can be almost 100 feet (30.5 meters) if put together.

子宫里的婴儿在妊娠晚期能听到低沉的声音，出生后，由于熟悉母亲的声音，他能很快辨别出母亲的声音。根据《卫报》网站上的一篇文章所述，婴儿的食物偏好也始于子宫，母亲在怀孕期间食用的口味很可能是新生儿偏好的口味。

A baby in the womb can hear muffled sounds by the third trimester and will identify the mother’s voice best after birth because of its familiarity. Its food preference also begins in the womb, and the flavors a mother consumes during pregnancy are likely to be preferred by the newborn child, according to an article on The Guardian’s website.

根据在《自然》杂志发布的调查结果，无论你是增重还是减重，每年约有 10% 的人体脂肪细胞会被新的脂肪细胞所取代。存储在这些细胞中的脂肪量会随着体重的增加或减少而变化。

Whether you are gaining or losing weight, every year around 10 percent of your body's fat cells are replaced with new fat cells, according to findings published in the journal Nature. The amount of fat stored in those cells varies with the increase or decrease in weight.

肌肉根据 jamaicahospital.org，在迈出一步时，大约有 200 块不同的肌肉协同工作。

About 200 different muscles work in coordination when you take one single step, according to jamaicahospital.org.

笑

当你笑的时候，富含氧气的营养物质和血液会流经你的身体。根据马里兰大学医学院的研究，笑能改善血管功能，降低心血管疾病的风险。

When you laugh, oxygen-rich nutrients and blood flow through the body. It improves the function of vessels, decreasing the risk of cardiovascular problems, according to research done by University of Maryland School of Medicine.

眼泪

美国眼科学会表示，眼睛每年产生大约 15-30 加仑的眼泪，这有助于清洁和保护眼睛健康。基本型眼泪有助于润滑和提供保护，反射型眼泪会在遇到刺激物（如烟雾或洋葱气味）时形成，而情感型眼泪由快乐、恐惧或悲伤等状态引起。

The American Academy of Ophthalmology says that the eyes produce about 15-30 gallons of tears every year, which help in cleaning and maintaining eye health. Basal tears help lubricate and protect, reflex tears form in response to irritants like smoke or onion fumes, while emotional tears arise due to states like happiness, fear or sadness.

身高

根据报告，我们早上比晚上高近 1 厘米。当我们进行日常活动时，脊柱和膝盖中的软骨会压缩，但是当我们睡觉时，软骨会恢复正常。

According to reports, we are nearly 1 cm taller in the morning than in the evening. The cartilage in our spine and knees compresses as we perform daily activities but while we sleep the cartilage goes back to normal.

While an average male has about 4 grams of iron distributed throughout the body, a female has about 3.5 grams, which is enough to make a metal nail measuring a few inches.