What does an average adult human brain weigh, in grams?
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🫀 Human body · grams
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Answer
About 1,400 grams
The brain makes up about 2 percent of body weight but uses roughly 20 percent of the body's energy at rest.
How to estimate it
Treat the brain as a ball that fits inside the skull, about 14 cm across. The volume of a sphere is 0.52 × diameter³, so 0.52 × 14 × 14 × 14 = 1,430 cubic centimetres. Brain tissue is mostly water, with a density close to 1 gram per cubic centimetre, which gives about 1,400 grams. The measured adult average is about 1,400 grams.
Source: Encyclopaedia Britannica
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