Human Brain Facts by the Numbers!

Human Brain Facts by the Numbers!

The most complex entity known resides between your ears.

April Beaulac

Brainiacs post 22 Dec

Here are some of the fascinating facts and figures about the human brain.

1. The typical brain is about 2% of a body’s weight but uses 20% of its total energy and oxygen intake. (2, 3)

2. Your brain is 73% water. It takes only 2% dehydration to affect your attention, memory and other cognitive skills. (4, 5)

3. Ninety minutes of sweating can temporarily shrink the brain as much as one year of aging. (6)

4. Your brain weighs about 3 pounds. Of that, the dry weight is 60% fat, making your brain the fattiest organ. (7)

5. 25% of the body’s cholesterol resides within the brain. Cholesterol is an integral part of every brain cell. Without adequate cholesterol, brain cells die. (8)

6. No one knows for sure, but the latest estimate is that our brains contain roughly 86 billion brain cells. (9)

7. Each neuron connects with, on average, 40,000 synapses. (10)

8. A piece of brain tissue the size of a grain of sand contains 100,000 neurons and 1 billion synapses all communicating with each other. (11)

9. All brain cells are not alike. There are as many as 10,000 specific types of neurons in the brain. (12)

10. Only 5 minutes without oxygen can cause brain damage. (13)

11. Babies have big heads to hold rapidly growing brains. A 2-year-old’s brain is 80% of adult size. (14)

12. As any parent can attest, teen brains are not fully formed until about the age of 25. (15)

13. Brain information moves at an impressive 260 miles per hour. This is faster than Formula 1 race cars which top out at 240 mph. (16, 17)

14. Your brain generates about 12-25 watts of electricity. Contrary to popular belief, this is not enough to power the average light bulb of 60 watts. (18)

15. The average brain has around 50,000 thoughts per day and 70% of them are believed to be negative. (19, 20)

16. More than 100,000 chemicals reactions take place in your brain every second. (21)

Does Brain Size Matter?

With some things size matters, but with the brain, bigger doesnt always mean better.

17. In general, men’s brains are 10% bigger than women’s, even after taking into account larger body size. (22)

18. Albert Einstein’s brain weighed in at 2.71 pounds — 10% smaller than the average of 3 pounds. (23)

19. Neanderthal brains were 10% larger than our homo sapiens brains. (24)

20. Humans don’t have the biggest brains. That honor belongs to sperm whales with 17 pound brains. (25)

The Effects of Modern Lifestyle on Our Brains

Our modern lifestyle is changing our brains. There’s some evidence it’s not all for the better.

21. Our brains are getting smaller. Over the past 10-20,000 years, the size of the average human brain has shrunk by the size of a tennis ball. (26)

22. We are not getting smarter. Since the Victorian era, average IQs have gone down 1.6 points per decade for a total of 13.35 points. (27)

23. Multitasking makes you less productive. When you multitask, your brain simply rapidly toggles back and forth between tasks. This results in decreases in attention span, learning, performance, and short-term memory. (28)

24. Surprisingly, millennials (aged 18 to 34) are more forgetful than baby boomers. They are more likely to forget what day it is or where they put their keys than their parents! (29)

25. We’ve always compared the brain to the most advanced technology of the day. It’s been compared to a clock, a switchboard, a computer, and most recently to the internet. (30, 31)