Human Body on ZME Science

Why Are Humans the Only Species to Cry Emotional Tears?

Darwin called them "purposeless", but emotional tears have their place.

Why do we sneeze when we look at light? The surprising world of photic sneezes

If you've got a case of the ACHOO, then you, like me (and Aristotle), sneeze when you look at light.

Looking younger than your age? It's a sign you're more protected from age-related illnesses

Naturally looking younger than your age isn't just a matter of vanity. It can be a tell-tale sign of one's underlying health.

The gut flora: how it affects your brain and health, according to scientists

The gut flora affects a lot of things in our body. This microbiome even affects your brain.

What's the ideal blood pressure by age: the Goldilocks of optimal heart health

Optimal blood pressure is critical to living a healthy life and staving off cardiovascular disease.

What causes hangovers? The science behind the dreadful morning after

There is no science-based cure for hangovers, but there are some helpful pointers.

Why do we stretch when we yawn?

We all do it.

Why getting a tattoo hurts -- the science behind inking

Humans have tattooed themselves since times immemorial to celebrate gods, show social standing, for medicinal purposes or just to look good. And since the dawn of this controversial form of art, people have endured excruciating pain to adorn their body with ink; but why does tattooing hurt so much?

6 Reasons Why Your Eye is Twitching

Never has something so benign been so annoying.

How eye color is determined: from brown to blue

Have you ever wondered why your eyes are the color they are? The answer lies in the complex world of eye color genetics.

Redheads do feel more pain -- and they're tougher than anyone else

Redheads might not have more fun, but they're definitely more interesting.

What is the most common blood type?

Have you ever wondered why people around the world have different blood types?

Designer babies may be coming soon. Here's why this matters

There's more than one way to "design" babies. Should we be worried?

What does it mean if your poop is green - do you need to see a doctor?

Many different factors can change your stool color, including diet, lifestyle, and health issues.

How tattoos are removed: everything you need to know

Not feeling your ex's name tattooed across your shoulder? Here's what you need to know before you have it removed.

What is the belly button and does it serve any purpose?

What does the belly button even do?

The Five Senses - our underrated superpowers

We take our senses for granted -- maybe we should cherish them more.

What is sleep paralysis: the unsettling phenomenon at the boundary of wakefulness

We undergo sleep paralysis every night and don't notice it -- unless we're awake when it happens.

You really shouldn't get an eye tattoo. Here's why

It's extremely dangerous, often leads to complications, and it's not even a true tattoo.

The artificial womb -- a fast-approaching frontier for humanity?

A dive into techno-ethical discussions around this potentially crucial science.

How a deaf Beethoven discovered bone conduction by attaching a rod to his piano and clenching it in his teeth

Beethoven wrote dozens of symphonies and songs while deaf. But he had some help from a nifty trick.

Pollen allergies are getting worse each year. Climate change and sexism are to blame

Are allergies getting worse? Yes -- and you can thank botanical sexism for that.

What is pain, and why do we even need it?

No carrot, all stick.

What is cholesterol?

Cholesterol is vital for the body's well-being. But too much of it can also kill.

What is hemoglobin, and should you worry that it's in your blood?

Any red-blooded American has this in their veins.

What function does the appendix serve?

Far from useless, the appendix is important for maintaining gut flora and supporting the immune system.

What is a stroke?

Know the signs and act FAST.

Can you die from lack of sleep?

In December 1963, two boys thought of a bright idea for a school science project– they would stay awake for as long as possible and report back on what happens inside their sleep-deprived brains. The project ended on 8 January 1964, when 17-year-old Randy Gardner had managed to stay awake for 11 days and 25 […]

Like a baby's bottom: why don't humans have fur?

We’re pink, bare, and proud of it! But also unsure as to why.

What time of day is pressure highest -- and other questions about hypertension

It's one of the most important health checkups.

Why do men have beards? An inquiry from an evolutionary biology perspective

There is limited evidence that beards make men more attractive. Instead, it's likelier that beards signal dominance to other men.

What are the benefits of breastfeeding?

Breast milk is a baby's first food and should be the only way of feeding infants for at least the first six months of life, according to the World Health Organization.