The human brain consumes about 20 percent of the body's energy and generates up to 25 watts.
Why it is true
Despite representing only about 2 percent of body weight, the brain is one of the most energy-demanding organs. It consumes approximately 20 percent of the oxygen and glucose we use, which is equivalent to about 25 watts of continuous power, enough to light a small lamp.
Source: Radio Itatiaia
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