Adrenaline

Japanese chemist Jokichi Takamine first isolated this hormone in 1901 and named it adrenaline, but American researchers had been working on the same compound and preferred "epinephrine." This sparked a century-long naming controversy that persists today—doctors in the US say epinephrine while the rest of the world uses adrenaline. The dispute became so heated that some medical journals refused to publish papers using the "wrong" name.

Those legendary stories of mothers lifting cars off trapped children aren't just folklore—adrenaline genuinely can unlock superhuman strength by overriding the brain's normal safety limits on muscle contraction. Your muscles are actually capable of much more force than you can normally access, but your nervous system restricts this to prevent injury. Adrenaline removes these brakes, though the superhuman feats often come with torn muscles and broken bones discovered later.

While we associate adrenaline with enhanced performance, it actually impairs fine motor skills and detailed thinking—exactly when you might need them most in an emergency. This is why trained professionals like surgeons and pilots spend countless hours drilling procedures until they become automatic, bypassing the adrenaline-impaired decision-making process. The hormone makes you stronger and faster, but also shakier and less precise.

During severe allergic reactions, adrenaline literally becomes the difference between life and death within minutes. Anaphylactic shock can kill in as little as six minutes, but adrenaline reverses every lethal symptom simultaneously—opening airways, raising blood pressure, and stopping the immune system's catastrophic overreaction. This is why EpiPens contain such a high dose that users often feel like they've been "hit by lightning."

Entire industries exist to deliver controlled adrenaline hits, from roller coasters engineered with precise G-forces to extreme sports that push just close enough to danger. What's fascinating is that adrenaline junkies develop tolerance just like with other drugs—yesterday's thrilling bungee jump becomes today's boring routine. This drives an escalating arms race of ever-more extreme experiences, as adventure companies compete to provide the next level of terror.

Your adrenaline system was perfectly designed for encountering a saber-toothed tiger, but it can't distinguish between genuine mortal peril and a work presentation. This evolutionary mismatch means you get the same hormonal flood from an angry email that your ancestors got from life-threatening predators. The result is that modern humans live in a state of chronic low-level adrenaline exposure, contributing to everything from insomnia to heart disease.