3 More Things You (Probably) Didn’t Know About the Brain

It probably comes as no surprise that we at Mindmore love teaching people about the brain. Many of you responded positively to our last list of 3 quick facts about the brain and asked for more.

So here it is: our latest list of 3 things you might not have known about the brain.

1. The brain is mostly fat

Many of us might have guessed the liver or some other organ, but no. By weight, the brain is the organ that contains the most fat. About 60 percent of the brain’s weight is fat (which, according to Guinness World Records, is a world record of sorts). That’s why it’s important to eat fats the brain likes, such as omega-3, which is found in large amounts in many types of fish.

The liver, by the way, is only about 5–10 percent fat.

2. The brain produces enough energy to light a light bulb

Many people know that the brain is our most energy-hungry organ. About 20 percent of our energy goes to the brain’s various activities. But did you know that the brain’s roughly 100 billion neurons generate electricity that could technically power a small light bulb? It’s true, and with that in mind, it may not be so strange that normal brain activity burns about ten calories an hour. And the more we engage the brain in different mental activities, the more calories it seems to need.

Keep that in mind the umpteenth time you see a PowerPoint presentation that uses this kind of illustration to signal creativity and bright ideas.

Further Reading:

Does Thinking Really Hard Burn More Calories? (Scientific American) Why Does the Brain Need So Much Power? (Scientific American)

3. The sperm whale has the heaviest brain

The heaviest brain in the animal kingdom belongs to the sperm whale. A sperm whale’s brain can weigh up to nine kilograms, compared with our own brain, which weighs only about 1.4 kilograms in adulthood. But if sperm whales could talk, maybe they shouldn’t brag too much. A sperm whale can grow to more than 20 meters long and weigh over 40 tons. Relative to their body weight, dolphins, for example, which show high social and emotional intelligence, have much heavier brains. Still, neither we humans, dolphins nor almost any other animal comes close to the shrew, which seems to have the heaviest brain of all relative to its body weight.