The human body is one of the most complex designs in nature. Here are some fun facts our biology texts didn’t teach us. 110 Interesting Facts about The Human Body.
1. All human beings are 99.9 per cent identical, on a genetic level. It is the 0.1% per cent change in DNA that makes all the difference.
2. We cannot breathe and swallow at the same time. But a newborn can for about 7 months.
3. If the amygdala is removed from the brain, we lose a sense of fear. Now don’t go about trying to removing this thing, because I’m afraid what it might do to you. Huh, anyway. Here’s the next one.
4. Our brain can remember up to 50,000 fragrances. Now you know how some smells could remind us of our childhood.
5. Our body dies faster due to sleep deprivation than starvation. You better get some good night’s sleep.
6. Lungs are the only organs in your body that float. They can float due to the air-filled alveolar structures inside the lungs.
7. Your right kidney is lower than the left kidney. It is due to the presence of the liver on the right side of the body.
8. Our noses and ears never stop growing. That’s because they’re made mostly of cartilage cells, which divide more as we age.
9. Women’s brains shrink during pregnancy. It takes up to 6 months to regain its original size.
10. Stomach acid is capable of dissolving metal. The mucus-bicarbonate layer protects the stomach lining from autodigestion by acid.
11. Tongue prints are unique just like fingerprints. It could be a new biometric authentication tool.
12. The crackling sound of knuckles is actually the sound of gas bubbles bursting in your joints’ synovial fluid. In order to crack the same knuckle again, you have to wait until the gases return to the synovial fluid.
13. Adults blink 10 times a minute while babies blink just once or twice. This could be because their ability to see is incomplete. So they have to work hard to soak in visual information.
14. The body loses about 4kg of skin cells every year. Though you can’t see it happening, we lose about 30,000 to 40,000 dead skin cells from the surface of our skin, every minute of the day.
15. The human heart beats about 3 billion times in an average life span. It pumps an amount of blood that equals about 1 million barrels.
16. While breathing most of the air goes in and out of only one nostril. After a few hours, the other nostril takes up this job.
17. Our teeth are coated with enamel. Brushing with too much force can wear out the enamel and cause sensitivity.
18. Seventy per cent of waste is eliminated through your lungs just by simply breathing. Guess what waste is that? Obviously carbon dioxide.
19. Babies don’t shed tears while crying until they are at least 1 month old. This is because a newborn’s tear ducts are not fully matured. Hence unable to produce actual tears.
20. The right lung is 10% per cent larger than the left lung. The left lung had to make room for the heart.
21. The brain produces enough electricity to light a bulb when we are awake. All your neurons together generate sufficient electricity to power a low-wattage bulb.
22. Our body emits very weak light. We can’t see this light because it is 1000 times less intense than to the levels in which our eyes are sensitive.
23. Astronauts can grow up to two inches taller in space. This is due to the expansion of disks of the spinal column. On Earth, the disks are slightly compressed due to gravity.
24. Blood makes up about 8% of the body weight. We have about 5 litres of blood circulating in our body.
25. We are 8mm taller in the morning than at night. This is because cartilage compresses during the day due to gravity.
26. The human body has more than 600 muscles. Skeletal, smooth, and cardiac are the 3 main types of muscle.
27. Humans are the only animals that can blush. It is the rush of adrenaline that makes us blush.
28. Eyes are made up of over 2 million working parts. You better take good care of it. Not easy to find a spare.
29. In the case of extreme starvation, the brain starts eating itself. This makes the feeling of hunger even stronger.
30. The human eye is about 576 megapixels. Even the best camera has only 200 megapixels.
31. Body organs aren’t all internal like the brain or the heart. There’s one we wear on the outside. Skin is our largest organ of the body. Adults have 20 square feet of skin.
32. Goosebumps helped our ancestors appear more threatening by making the hairs stand up. Now it just makes us look scared.
33. Have you ever felt like your heart beats to the rhythm of the music? Well, it is true. Heartbeat syncs with the rhythm while listening to music.
34. 50% of our hand strength comes from our pinky finger. Looks can be deceiving.
35. The cornea is the only part of the body with no blood vessels. Our eyes can directly get oxygen from the air.
36. Our brain can survive up to 10 minutes without oxygen. But it can cause some serious damage to the brain.
37. 1 litre of saliva is produced each day by our mouth. A total of 25000 litres of saliva is produced in a lifetime. This can fill two swimming pools.
38. The highest blood flow is in our kidneys and not the heart. This is because kidneys are the body’s natural filtration system.
39. Hair grows 6 inches every year. Only bone marrow grows faster than hair in the body.
40. All of the blood vessels in the human body would encircle the Earth four times when laid end to end. They are more than 60,000 miles long.
41. Only humans have chins. Maybe, that’s why we are so much better looking.
42. Healthy lungs look pink. A smoker’s lungs are in grey-black colour due to the buildup of tar from cigarette smoke.
43. Oxygen is the most abundant element in the human body. It accounts for 65% of a person’s mass.
44. Femur aka thighbone is the strongest, heaviest, and longest bone in the human body. All of the body’s weight is supported by the femurs during many activities, such as running, jumping, walking, and standing.
45. An average human has about 2-5 million sweat glands. Did you know that stress sweat and regular sweat are composed of different things? Stress sweat has fatty acids in it while regular sweat doesn’t.
46. The human body contains enough fat to make seven bars of soap. Fats are stored mainly under the skin.
47. Our body contains trace amounts of gold. A person weighing 70kg contains 0.2 mg of gold.
48. The human nose can detect about 1 trillion smells. It has around 400 types of scent receptors.
49. An average human adult has about 3000-4000 taste buds. It is not just on the tongue but at the back of the throat, inside the nose and oesophagus as well.
50. One-fourth of the bones in our body is located in the feet. Each normal foot has 33 joints, 26 bones, 19 muscles, and 107 ligaments.
51. Teeth are the only part of the human body that is not capable of healing itself. You better take good care of your teeth.
52. The stapedius muscle, located in the middle of your ear, is the weakest muscle. At just over one millimetre in length, its purpose is to stabilize the smallest bone in the body, the stapes.
53. The fastest muscles in the body are the extraocular muscles in the eye. They allow both of your eyes to flick in the same direction in a single 50-millisecond movement. Hence, the phrase: “In the blink of an eye.”
54. Fingernails grow faster than your toenails. Fingernails may need more replacing since our fingers are busier than our toes.
55. 80% of the body heat is lost from the head. Because this is the only part of your body that is left uncovered mostly.
56. 10-20% of the human population can wiggle ears. Are you one of them?
57. Right-handed people are likely to live 9 years more than left-handed people. This could be because left-handers live in a world designed for right-handers.
58. 90% of dreams are forgotten. No surprise there.
59. Your brain is sometimes more active when you’re asleep than when you’re awake. Is that why you sleep in class?
60. The small intestine is about 10 feet long. It is 5 times longer than the large intestine. Wondering why is it called small? It is due to its relatively smaller diameter.
61. The liver can hold up to 10 per cent of the blood in the body. It pumps nearly 1.5 litres through itself per minute.
62. Our skin is home to 1000 different species of bacteria. Who knew our skin is an ecosystem.
63. Embryos develop fingerprints three months after conception. They are completely formed by the time a fetus is 6 months old, that’s 3 months before the baby is born!
64. 100,000 chemical reactions occur in the human brain every second. With 86 billion cells and over 10,000 types of neurons, the human brain is probably the most complex entity known to man.
65. The human eye can distinguish 10 million different colours. The retina has millions of tiny parts called cones. Red, blue, and green are the 3 main kinds of it. It’s these three kinds of cones that work together and allow you to see millions of colours.
66. The liver is the only organ that can regenerate itself. You can lose up to 75 per cent of your liver, and the remaining parts can regenerate itself into a whole liver again.
67. The human skeleton is composed of around 305 bones at birth. It decreases to 206 bones by adulthood after some bones have fused together.
68. Men’s hearts beat slower than women. This is because women’s hearts are smaller in size and need to beat more to pump the same amount of blood.
69. 99% of the calcium present in the human body is in teeth. It provides strength to teeth.
70. Your heart beats around 100,000 times a day. The sound you hear when it beats is actually the noise of the heart valves opening and closing.
71. Erythrocytes or red blood cells are the most abundant cells in our body. Its main job is to deliver oxygen to the body’s tissues.
72. The human heart is approximately equal to the size of a closed fist. This fist-sized powerhouse pumps about 2,000 gallons of blood per day.
73. Stapes, one of the ear ossicles is the smallest bone in the body. It conveys the sound from the outer ear to the inner ear.
74. The biggest artery in your body, the aorta, is as large as a garden hose. It runs from your heart to your belly.
75. More calories are burnt while sleeping than watching TV. Now that is a weight loss tip that can be easily followed.
76. Crying is a natural pain killer. It reduces both emotional and physical pain.
77. The human heart pumps blood at such pressure that it would be able to raise blood up to the fourth floor of a building. Surprising, isn’t it?
78. The human brain cell can hold five times as much information as an encyclopedia. We are smarter than we think.
79. We use 17 muscles when we smile, and 43 when we frown. It is easier to smile. So why don’t you smile more?
80. Some capillaries are ten times smaller than a human hair. They are so small that blood cells have to travel single-file through them.
81. The most common eye colour is brown. Brown eyes are blue eyes underneath.
82. Sneezes travel at about 100 miles per hour. A single sneeze can send 100,000 germs into the air.
83. Most heart attacks occur on Monday. It is likely due to the stress of returning to work.
84. The bone is stronger than steel. One cubic inch of bone can withstand 8619kg.
85. You cannot sneeze with your eyes open. This prevents the entry of exhaled irritants into the eyes.
86. Eyelashes last about 150 days. It is normal to lose 1-4 eyelashes every day.
87. There are 50,000 sweat glands in our feet. Now you know why your feet smell.
88. 80% of the brain is water. Even slight dehydration can cause fatigue, headaches, lack of mental clarity, and sleep issues. So better stay hydrated.
89. Sweat glands are responsible for keeping the body moisturized. The lips dry so fast because there are no sweat glands around the area. So, keep your lip balm handy.
90. Lungs and tennis courts can be of the same size. It seems pretty impossible, but if the lungs were opened flat they would be so big that they would cover the size of a tennis court!
91. We share 98.4% of our DNA with a chimpanzee, 70% with a slug, and 50% with bananas. I’m speechless.
92. Everyone has a unique smell except identical twins. They smell the same.
93. Humans are the only animals that cry when they are sad. Other animals shed tears to lubricate their eyes.
94. You cannot tickle yourself. Because you can’t surprise your brain. The unpredictability is what makes you more sensitive and causes you to laugh.
95. People who dream often have a higher IQ. This is because those who have a higher IQ tend to process more information than others and there are more thoughts going through the mind.
96. Everyone’s lip mark is unique, just like fingerprints. Wonder if that helps in solving any type of crime?
97. There are around 100,000 hair follicles on an average person. Each follicle can grow about 20 individual hairs in a person’s lifetime.
98. Enamel is the hardest substance in our body. It is made up of mostly minerals, primarily hydroxyapatite.
99. The average human body has enough iron in it to forge a 3-inches long metal nail, enough carbon to make 900 pencils, and enough phosphorous to make 2,200 match heads.
100. Less than one-third of the human race has 20-20 vision. This means that two out of three people cannot see perfectly.
101. The lifespan of a human hair is 3 to 7 years on average. It is normal to lose about 100 hair every day.
102. Chances of having a bad dream will increase in a cold room. It would be a bad idea to sleep in one especially if you’ve watched a horror movie.
103. 300 million cells die in the human body every minute. There are about 50-100 trillion cells in our body.
104. Our ears secrete more earwax when we are afraid than when we aren’t. It’s probably because of increased sweating. Ear wax is made of oil and sweat.
105. Sweat doesn’t smell bad. Waste products of bacteria feeding on them causes body odour.
106. Red hair is the rarest hair colour in the world. It occurs only in 1 to 2% of the global population.
107. The biggest toe can carry 40% of the body weight. This toe is the last part of the foot to push off the ground before taking the next step.
108. 20% more fat can be burnt by exercising in the morning on an empty stomach. Now you know the perfect time for your workout.
109. Half of your genes describe the complex design of your brain, with the other half describing the organization of the other 98% of your body.
110. In times of fear, our body is physically stronger. We can lift 12% more weight than usual. What doesn’t kill you makes you stronger.
That was 110 interesting facts about the human body.