Cramming for a test? Trying to get more done than you have time to do?
正在为考试临阵磨枪？尝试在有限的时间内完成更多的事儿？
Stress is a feeling we all experience when we are challenged or overwhelmed.
当面临挑战或感到无助时，我们可以清晰的感受到压力的存在。
But more than just an emotion, stress is a hardwired physical response that travels throughout your entire body.
但压力不仅仅是一种情绪，它还是一种穿行在我们体内的身体反应，就像电路板上的电流那样。
In the short term, stress can be advantageous,
短期来看，压力有着积极作用；
but when activated too often or too long, your primitive fight or flight stress response not only changes your brain
但是当压力出现的过于频繁，持续的过长时，它产生的反应不仅仅会影响到你的大脑，
but also damages many of the other organs and cells throughout your body.
还会对你全身的器官与细胞造成伤害。
Your adrenal gland releases the stress hormones cortisol, epinephrine, also known as adrenaline, and norepinephrine.
你的肾上腺会释放压力荷尔蒙皮质醇，肾上腺素以及去甲肾上腺素。
As these hormones travel through your blood stream, they easily reach your blood vessels and heart.
所有的这些激素在你的血液系统中穿行着，它们可以轻易的到达你的血管和心脏。
Adrenaline causes your heart to beat faster and raises your blood pressure, over time causing hypertension.
肾上腺素会使你的心跳加速、血压升高，时间长了还会引发高血压。
Cortisol can also cause the endothelium, or inner lining of blood vessels, to not function normally.
压力荷尔蒙皮质醇会令你的内循环或血管中的内覆组织无法正常运行。
Scientists now know that this is an early step in triggering the process of atherosclerosis or cholesterol plaque build up in your arteries.
如今，科学家发现这些还是产生动脉硬化以及胆固醇斑块化的早期诱因。
Together, these changes increase your chances of a heart attack or stroke.
同时，它们还会增加心脏病或中风的患病几率。
When your brain senses stress, it activates your autonomic nervous system.
当你的大脑感受到压力时，它会激活你的自主神经系统。
Through this network of nerve connections,
通过这个系统中神经纤维间的联系，
your big brain communicates stress to your enteric, or intestinal nervous system.
你的大脑向你的肠道，或者说肠神经系统传递了压力的信号。
Besides causing butterflies in your stomach,
除了会令你紧张外（肠胃颤动），
this brain-gut connection can disturb the natural rhythmic contractions that move food through your gut,
这个大脑与肠胃之间的联系还会打断有节奏的肠胃收缩（正是这种收缩帮助食物蠕动进了胃里），
leading to irritable bowel syndrome, and can increase your gut sensitivity to acid, making you more likely to feel heartburn.
导致肠道易激综合症；同时使你更容易患上胃酸、胃灼热。

Via the gut's nervous system, stress can also change the composition and function of your gut bacteria,
通过肠神经系统，压力还会改变肠道细菌的成分和功能，
which may affect your digestive and overall health.
而这可能会使你消化不良，甚至影响你整个身体的健康。
Speaking of digestion, does chronic stress affect your waistline?
说到消化功能，那么长期的处于压力之中会否使人变胖呢？
Well, yes. Cortisol can increase your appetite.
答案是肯定的。肾上腺皮质醇会增加你的食欲。
It tells your body to replenish your energy stores with energy dense foods and carbs, causing you to crave comfort foods.
它会向身体释放饥饿信号，进而促使你去进食大量的高能量食物和碳水化合物来补充能量储存。
High levels of cortisol can also cause you to put on those extra calories as visceral or deep belly fat.
肾上腺皮质醇甚至可以释放更高级的信号，让身体将多余的卡路里转化为内脏脂肪或者皮下脂肪。
This type of fat doesn't just make it harder to button your pants.
这种类型的脂肪不仅仅是令你胖到难以找到能穿的衣服。
It is an organ that actively releases hormones and immune system chemicals called cytokines
它还是一种被叫做细胞因子的器官，功效就是释放荷尔蒙以及和免疫系统相关的化学物质，
that can increase your risk of developing chronic diseases, such as heart disease and insulin resistance.
它会大大增加慢性疾病的患病几率，如心脏疾病和胰岛素抵抗。
Meanwhile, stress hormones affect immune cells in a variety of ways.
同时，压力荷尔蒙还会以多种方式影响免疫细胞。
Initially, they help prepare to fight invaders and heal after injury,
原本免疫细胞可以帮助抵御外来病菌、治愈外部伤口，
but chronic stress can dampen function of some immune cells,
但慢性压力会抑制某些免疫细胞的功能，
make you more susceptible to infections, and slow the rate you heal.
进而增加身体受感染的几率，延缓身体的自愈速度。
Want to live a long life? You may have to curb your chronic stress.
想要活的更长寿么？你或许需要减少你的慢性压力了。
That's because it has even been associated with shortened telomeres,
因为它甚至会令你的染色体终端变短，
the shoelace tip ends of chromosomes that measure a cell's age.
而染色体的这个端粒恰恰影响着细胞的寿命。
Telomeres cap chromosomes to allow DNA to get copied every time a cell divides without damaging the cell's genetic code,
每次细胞分裂的时候，染色体端粒帽保证着细胞可以正确复制细胞的遗传代码。
and they shorten with each cell division.
同时，随着细胞的分裂，它们也在不断变短。
When telomeres become too short, a cell can no longer divide and it dies.
当染色体终端太短时，细胞也就无法再分裂了，这意味着一个细胞的死亡。
As if all that weren't enough, chronic stress has even more ways it can sabotage your health,
不仅仅是这些，慢性压力还会从更多的方面去危害你的健康，
including acne, hair loss, sexual dysfunction, headaches,
比如痤疮、脱发、性功能障碍、头痛、
muscle tension, difficulty concentrating, fatigue, and irritability.
肌张力、精神难以集中、疲劳还有易怒等症状。
So, what does all this mean for you?
那么，这些对你又意味着什么呢？
Your life will always be filled with stressful situations.
你的生活将始终充斥着压力。
But what matters to your brain and entire body is how you respond to that stress.
重要的是你的大脑和身体是如何应对这些压力的。
If you can view those situations as challenges you can control and master,
如果你能够将这些压力视为可以控制的挑战，
rather than as threats that are insurmountable,
而非无法抗拒的威胁的话，
you will perform better in the short run and stay healthy in the long run.
你的生活一定会更加的高效、健康。