The human body is truly amazing. It’s so good at protecting itself that you rarely think about all the things it does right every day. The following 10 facts about the human body will really put into perspective how impressive your body really is. Let’s get started!
1) The human body doesn’t know its own limits
1. The human body is an incredible machine that is constantly pushing its own limits. 2. For example, did you know that the average person can only survive for three to four days without water? 3. And yet, some people have gone without food for weeks or even months! 4. The human body is truly amazing and can adapt to almost any situation. 5. So next time you think you can’t do something, remember that your body is capable of so much more than you realize.
2) There are places in our bodies where blood flows backwards
Did you know that there are actually places in our bodies where blood flows backwards? It's true! The pulmonary and systemic circuits are two examples of this. In the pulmonary circuit, blood flows from the right ventricle of the heart to the lungs and back again. In the systemic circuit, blood flows from the left ventricle of the heart to the rest of the body and back again.
3) We don’t digest food – it digests us
The human stomach is incredibly acidic, with a pH of around 1.5. This acid is strong enough to dissolve metal, and it’s secreted by cells that line the stomach. When we eat, these cells secrete even more acid to break down our food. But our food doesn’t just dissolve in this acid – it’s also digested by it. The cells that line our stomach walls have tiny hair-like projections called microvilli.
4) Humans are part bacteria
Believe it or not, we're not 100% human. In fact, we're only about 43% human. The rest of our DNA is made up of bacteria, viruses, and other microorganisms that call our bodies home. The most interesting part? We need these little guys to survive. They keep us healthy by attacking harmful invaders like bacteria and fungi, creating vitamins like B12, and helping us process nutrients from food so they can be used by the body.
It's time to stop worrying about whether you have too many microbes on your hands or in your mouth: they might just be keeping you alive!
5) Our brains take up less energy than any other organ in our bodies
The human brain is only about 2% of our body weight, yet it uses 20% of the energy our bodies produce. In fact, our brains are so energy-hungry that they consume about 300 calories a day – that’s more than a quarter of the average person’s daily intake.
6) Our hearts beat for over 100,000 miles
The average person's heart will beat about 3.5 billion times in their lifetime and pump around 2,000 gallons of blood each day. That means that in an average lifespan, our hearts will beat for more than 100,000 miles.
7) Surprising things you didn’t know about ears
The human ear is an incredible feat of engineering. The outer ear collects sound waves and funnels them into the middle ear, where they vibrate three tiny bones. These vibrations are then passed along to the inner ear, where they are converted into electrical signals that are sent to the brain. The brain interprets these signals as sound.
8) The amount of time it takes your heart to stop after you die is shorter than most people think
Most people think that once you die, your heart stops immediately. However, it actually takes your heart a few minutes to stop. This is because your body is still trying to pump blood to your brain and other organs. Even after you die, your body is still working!
9) In most animals, males give birth to their young (In humans, females do.)
Did you know that in most animals, it's the males that give birth to their young? In humans, of course, it's the females that carry and give birth to babies. But in a majority of animal species, it's actually the males that are responsible for giving birth.
10) Death begins when we lose consciousness
Did you know that death actually begins when we lose consciousness? Once our brain is without oxygen for just six minutes, it starts to die. And once our heart stops pumping blood, we only have about another four minutes before we're officially gone. Crazy, right?
But what's even crazier is that our bodies are constantly fighting to keep us alive. Our hearts beat an average of 100,000 times a day and pump about 2,000 gallons of blood.