Your body is doing some seriously odd things right now. Some of them involve organs you never think about, and some involve passengers you didn’t know you had.
We’ve ranked seven facts that sound too strange to be real but are well established. The countdown ends with the one we think is the most fascinating and the most useful, because it’s something you can act on at your very next meal.
7. You were born with more bones than you have now
You start life with more bones than you will ever finish with. A newborn has somewhere over 270 bones and pieces of cartilage, and many of them fuse together as the child grows. By adulthood the count settles at 206.
The soft gaps in a baby’s skull are part of the design. They let the head squeeze through the birth canal and leave room for the brain to grow quickly in the early months. Over time the plates knit together into a solid, protective shell. Your skeleton isn’t a fixed frame, either. It keeps remodelling itself throughout life.
Pro tip: If you ever hold a newborn, always support the head and neck, because those soft areas are the reason.
6. Identical twins still have different fingerprints
Your fingerprints started forming before you were born, and they belong to you alone. Even identical twins, who share the same DNA, have different prints, because the pattern is shaped partly by chance conditions in the womb. No two people are known to share the same set.
The ridges aren’t just decoration. They are thought to help with grip and to sharpen your sense of fine texture, which is why a smooth surface feels so different from a rough one under your fingertips. Once formed, your pattern stays the same for life, although cuts and wear can affect how clear it looks.
5. The front of your eye has no blood supply
The clear dome at the front of your eye, the cornea, contains no blood vessels. That keeps it transparent, which is exactly what you need for seeing clearly. Blood vessels would get in the way of the light.
So where does it get its oxygen? Largely straight from the air when your eyes are open, helped by the thin film of tears that coats the surface.
It’s also why contact lens advice is so strict. Lenses sit directly on that surface, so wearing them for too long or sleeping in them when you shouldn’t can cause real problems.
Pro tip: Don’t sleep in your lenses unless your optician has told you your specific type is designed for it.
4. Your heart has its own built-in pacemaker
Your heart doesn’t wait for instructions from your brain to beat. A small cluster of specialised cells, called the sinoatrial node, acts as a natural pacemaker. It sends out regular electrical signals that make the heart muscle contract, again and again, without you ever thinking about it.
The nervous system still adjusts the pace. That’s why your pulse races when you’re nervous or running for a bus, and eases when you relax. The rhythm is built in and the brain just turns the dial. Over a lifetime, it adds up to billions of beats.
Pro tip: You can find your pulse by placing two fingers on your inner wrist, and a GP can advise if your readings ever worry you.
3. Your liver can regrow itself
Few organs can match the liver for recovery. If part of it is removed or damaged, the remaining healthy tissue can multiply and restore much of what was lost. It’s the reason living liver donation is possible: a portion can be given to someone else, and in the right circumstances both the donor’s and the recipient’s livers can grow back towards a working size.
There are limits, though. Long-term heavy drinking and certain diseases can cause scarring that the liver cannot undo. Its talent for repair is not a licence to take it for granted.
Pro tip: Follow national alcohol guidance, and speak to a GP if you’re concerned about your liver health.
2. Your brain is a huge energy hog
Your brain makes up only about 2% of your body weight, yet it uses roughly 20% of the energy your body burns at rest. Thinking, sensing, balancing and keeping everything else ticking over is costly work, even when you feel as though you’re doing nothing at all.
It runs mostly on glucose and needs a constant supply of oxygen, which is why it reacts so quickly when either dips. It also explains why a long stretch without food or sleep can leave you foggy, forgetful and short-tempered.
Pro tip: Regular meals and a consistent bedtime are simple ways to look after your concentration.
1. You share your body with trillions of microbes
You are not just you. Your body, especially your gut, is home to trillions of microbes, mostly bacteria but also fungi and viruses. Current estimates suggest you carry roughly as many bacterial cells as human ones. They help break down food, make some vitamins and help train your immune system.
Here’s the useful part: you can feed them. Gut bacteria thrive on the fibre found in a varied mix of plants, such as beans, oats, vegetables, fruit, nuts and seeds. Variety matters more than any single trendy ingredient, because different microbes prefer different foods.
Pro tip: Add one new plant food to your weekly shop and build up gradually, as sudden fibre jumps can cause bloating. If you have a digestive condition, check with a GP or dietitian first.
The human body is stranger and cleverer than most of us give it credit for. Which fact surprised you most, and have we missed a favourite? Tell us your own picks in the comments.
