Body & HealthFact

Your brain runs on the power of a dim light bulb.

The brain weighs about 1.4 kilograms, roughly 2 percent of your body, yet uses around 20 percent of your resting energy. That is about 20 watts. Most of it goes not to conscious thought but to basic upkeep: ion pumps that constantly recharge nerve cells. Hard thinking raises consumption by only a few percent.

Useful: That is why thinking feels tiring without burning a measurable number of calories.

Source: doi.org

Energie Gehirn

Difficulty:

Question on this card

Roughly what share of your resting energy does the brain use?

2 percent
10 percent
20 percent
50 percent

Show the answer

Correct: 20 percent

About 20 percent, despite being only 2 percent of body weight, roughly 20 watts.

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