The human body is an incredibly complex.

Some of the facts you are about to read may seem unbelievable but they are actually true and most of them are processes that are happening in your body right now.

Here are 50 lesser-known human body facts that might surprise you:

  1. Scientists don’t know why, but the brain is more active at night than during the day.
  2. The higher your IQ, the more dreams you have.
  3. Facial hair is the fastest growing hair on the human body.
  4. The middle fingernail grows faster than the other fingernails.
  5. Human fingernails grow about four times as fast as toe nails.
  6. The average lifespan of a human hair is 3 to 7 years.
  7. Your stomach acid is so strong that it can dissolve zinc, yet it doesn’t destroy the lining of the stomach because the stomach walls are constantly renewed.
  8. Women’s hearts beat faster than men’s hearts.
  9. Women blink twice as often as men do.
  10. Girls are born with a better sense of smell than boys, and women remain better smellers than men throughout life.
  11. Men burn 50 more calories of fat per day than women.
  12. Men get the hiccups more often than women do.
  13. Men have about 6.8 liters of blood in their bodies and women have about 5 liters.
  14. The female egg is the largest cell in the human body and the male sperm is the smallest.
  15. During your lifetime, you will produce enough saliva to fill a couple of swimming pools.
  16. Babies are always born with blue eyes because the melanin in their eyes takes time to be fully deposited or to be darkened by ultraviolet light to reveal the baby’s true eye color.
  17. While men sleep, they typically get an erection every hour to hour-and-a-half.  This is due to the combination of blood circulation and testosterone production, and it’s a necessary part of REM sleep.
  18. After overeating at a meal, your hearing is not as good as it was before you ate.
  19. Without your saliva to dissolve and mix with your food, you would not be able to taste the food you eat.
  20. Noises—both soft and loud—can cause the pupils of the eyes to dilate.
  21. Every single person has a unique smell, unique finger print and unique tongue print.
  22. Most people lose half their taste buds by age 60.
  23. Your eyes remain the same size from birth until the end of your life, but your nose and ears continue to grow throughout your life.
  24. A moderately severe sunburn burns the blood vessels, so never allow yourself to get a sunburn.
  25. Humans are approximately 1 cm taller in the morning than at night.
  26. The tongue is the strongest muscle in the human body.
  27. The jaw bone is the hardest bone in the human body.
  28. Human hands and feet contain almost half of the total number of bones in the body.
  29. Every inch of your skin is home to approximately 32 million bacteria. Thankfully, most of them are harmless and many of them are beneficial to your health.
  30. Every 27 days, humans shed and regrow the outer layer of their skin.
  31. Every single minute, 300 million cells die in the human body, and everyday adult humans produce 300 billion new cells.
  32. The colder the room is that you sleep in, the higher your chances are to have a nightmare.
  33. The only species that produces emotional tears is humans.
  34. At birth, all babies are colorblind and only see black and white.
  35. The corneas in your eyes are the only parts of the body that have no blood supply. They get oxygen directly from the air.
  36. An average person can survive about 20 days without eating any food but can survive only about 2 days without drinking any fluids.
  37. Everyone has one eye that sees better than the other.
  38. Your body constantly works to rebuild your bones, so every ten years, you have a completely new skeleton.
  39. Humans have 500,000 sweat glands on their feet that are capable of producing more than a pint of sweat per day.
  40. The speed of the nerve impulses that travel from and to the brain reaches up to 250 miles per hour.
  41. Our bodies completely replace our old skin with a new one every month. In his lifetime, a person sheds 40 pounds of their skin.
  42. The atoms that our bodies are made of are 13.7 billion years old as they are the same ones that were formed during the Big Bang.
  43. Some people, and in particular WOMEN  have the ability to see a wider range of colors than an average person can. Most of us have 3 types of color receptors, but some WOMEN
    have 4 or 5 of these.
  44. The strength of our bones can be compared to the strength of granite. A matchbox sized block of human bone could support 9 tons.
  45. When we are in love, our bodies release the same variety of neurotransmitters and hormones that are released when under the influence of amphetamines. The common symptoms are loss of sleep and appetite, feelings of excitement and increased heart rate.
  46. The muscles in our eyes that are responsible for focusing, move 100 000 times every day. If you want to do the same workout but with your legs, you would have to walk 50 miles.
  47. Our bodies give off so much heat for 30 minutes that would be enough to boil a gallon of water.
  48. 50% of a human’s DNA is the same as a banana’s.
  49. Our eyes are impressively sensitive organs, too. They are so sensitive that if the Earth was flat, you could see a candle burning at night from 30 miles away.
  50. If our brains were computers, they could perform 38 thousand-trillion operations for a second. In comparison, the most powerful supercomputer in the world can do only 0.002% of that.The human body has around 60 000 miles of blood vessels in average. The Earth can be circumnavigated two and a half times with that length.