ONE WILD WORLD — NEWSLETTER
Issue #004 | Your Body Is Wild | April 2026
Your Stomach Can Dissolve a Razor Blade
The acid inside you right now is strong enough to corrode metal, melt steel, and dissolve a razor blade in under 24 hours. The only thing stopping it from eating you alive is a paper-thin layer of mucus that your body replaces every three days - or else...
BY THE NUMBERS
pH 1–2 | Acidity of your stomach acid — nearly as strong as battery acid |
37% | Weight a razor blade loses after 24 hours in stomach acid |
2 hours | Time for stomach acid to dissolve the thickened back of a blade |
3 days | How often your stomach lining completely replaces itself |
2,000 gal | Amount of blood your heart pumps through vessels every single day |
The Acid Factory in Your Belly
Right now, your stomach contains hydrochloric acid with a pH between 1 and 2. To put that in perspective, battery acid has a pH of about 1. Lemon juice is around 2. Your stomach acid is closer to battery acid than lemon juice.
This acid is produced by specialized cells in your stomach lining called parietal cells. They secrete it continuously, creating an environment so corrosive that almost nothing organic can survive in it. Bacteria, viruses, parasites — most are destroyed on contact.
But the truly jaw-dropping part? This same acid can dissolve metal.
The Razor Blade Experiment
In 1997, a team of researchers published a study in the journal Gastrointestinal Endoscopy that put this to the test. They submerged razor blades, disc batteries, and coins in simulated gastric juice — a solution with the same chemical properties as human stomach acid — and observed what happened over 24 hours.
The results were remarkable. After 24 hours, the razor blades had lost approximately 37% of their original weight. The thickened back of a single-edged blade dissolved completely in just two hours. After 15 hours, double-edged blades had become so brittle they could be snapped with a simple tool.
IMPORTANT CONTEXT The researchers conducted this study to help doctors manage cases where patients (often children or psychiatric patients) had swallowed metal objects. The finding that stomach acid rapidly corrodes thin metal helped guide the timing of endoscopic removal procedures. Coins, interestingly, were completely unaffected — which is why swallowed pennies tend to pass through without issue. |
So Why Doesn’t It Eat You Alive?
This is the real question. If your stomach acid can dissolve a razor blade, how does your stomach survive?
The answer is a thin, constantly regenerating layer of mucus. Your stomach lining is coated with a mucous barrier made of glycoproteins and sugar molecules that resist the acid. This barrier is astonishingly thin — less than a millimeter — yet it’s the only thing standing between the acid and your own tissue.
And here’s the remarkable part: your body completely replaces this entire lining every three to four days. The cells that make up your stomach wall are destroyed by the acid constantly, but they reproduce so rapidly that the damage is repaired before it can accumulate.
Your stomach is in a perpetual arms race with itself — producing acid strong enough to dissolve metal while simultaneously rebuilding the walls that contain it, every 72 hours. |
When this system breaks down — when the mucus layer is damaged faster than it can regenerate — the acid eats into the stomach wall itself. That’s an ulcer. For decades, doctors blamed ulcers on stress and spicy food. It wasn’t until 1982 that two Australian researchers, Barry Marshall and Robin Warren, discovered that most ulcers are actually caused by a bacterium called Helicobacter pylori that burrows into the mucus layer and weakens it. They won the Nobel Prize in 2005 for this discovery.
Your Body’s Other Quiet Superpowers
Your stomach is far from the only part of your body doing extraordinary things without your awareness.
Your blood vessels, laid end to end, would stretch for roughly 60,000 to 100,000 miles — enough to circle the Earth four times. Your heart pumps approximately 2,000 gallons of blood through this network every single day, and it does this without stopping for your entire life.
Your skin — your largest organ — replaces itself entirely roughly every 27 days. You shed about 600,000 particles of skin every hour, which adds up to approximately 1.5 pounds of dead skin per year. By the time you reach 70, you will have shed about 105 pounds of skin.
YOUR GUT IS YOUR SECOND BRAIN Your gastrointestinal system contains its own independent nervous system with over 100 million neurons — more than your spinal cord. It produces approximately 95% of your body’s serotonin, the neurotransmitter that regulates mood, sleep, and well-being. Scientists increasingly refer to the gut as the “second brain” because of its ability to operate independently and its profound influence on mental health. |
Your body emits light. It’s extremely faint — about 1,000 times weaker than what the human eye can detect — but bioluminescent reactions in your cells produce tiny amounts of visible light throughout the day, with intensity fluctuating on a 24-hour cycle.
And every atom of calcium in your bones, every molecule of iron in your blood, every trace of carbon in your muscles was forged in the heart of a dying star billions of years ago. You are, quite literally, made of stardust.
Acid that dissolves metal. A lining that rebuilds itself every three days. A gut that controls your mood. A body that glows in the dark.
You are far stranger than you think.
WHAT?! Facts you never asked for. Knowledge you can’t unsee. Follow us on X: @ItsOneWildWorld Share this newsletter with someone who needs to know. |
SOURCES
Li PK et al. — “In vitro effects of simulated gastric juice on swallowed metal objects”, Gastrointestinal Endoscopy (1997)
INTEGRIS Health — “Mind-Blowing Facts About the Human Body You Never Knew”
HowStuffWorks — “16 Unusual Facts About the Human Body”
Nobel Prize Committee — Marshall & Warren, Nobel Prize in Physiology or Medicine (2005)