How much energy is in the brain?
Despite this, even at rest, the brain consumes 20% of the body's energy. The brain consumes energy at 10 times the rate of the rest of the body per gram of tissue. The average power consumption of a typical adult is 100 Watts and the brain consumes 20% of this making the power of the brain 20 W.
So an average adult brain being about 3 pounds burns 327 calories per day! In general, vital organs make up only about 5-6% of our total mass but 60% of our total resting energy expenditure (REE).
- If you're using a standing desk in an effort to burn more calories, University of Pittsburgh researchers have some bad news for you. The scientists measured exactly how many calories people expended while sitting or standing for 15 minutes. That translates to an extra 8 to 10 calories for every hour on your feet.
- Just like other cells in the body, brain cells use a form of sugar called glucose to fuel cellular activities. This energy comes from the foods we consume daily and is regularly delivered to brain cells (called neurons) through the blood.
- The human brain weighs on average three pounds, or 1.5 kg. The human brain is about the size of a cantaloupe. How much oxygen does the brain need to stay "conscious"? An adults brain requires around 20% of the body's oxygen.
RMR varies from person to person depending on age, gender, size and health. If we assume an average resting metabolic rate of 1,300 calories, then the brain consumes 260 of those calories just to keep things in order. That's 10.8 calories every hour or 0.18 calories each minute.
- Age has a significant effect on caloric burn while talking. A young man of 18 years and 150 lbs. will burn 57 calories per hour of talking, while an older gentleman of 80 years of the same height and weight will burn 43 calories for the same amount of talking.
- Our bodies produce sweat as a way to cool down, so if anything, it's an indicator of how hot your body is. And hotter core temperatures don't equal more calories burned. In fact, the fitter you are, the less you probably sweat. After all, sweating depends on having water to spare.
- The brain consumes energy at 10 times the rate of the rest of the body per gram of tissue. The average power consumption of a typical adult is 100 Watts and the brain consumes 20% of this making the power of the brain 20 W.
Just like other cells in the body, brain cells use a form of sugar called glucose to fuel cellular activities. This energy comes from the foods we consume daily and is regularly delivered to brain cells (called neurons) through the blood.
- Grey matter contains most of the brain's neuronal cell bodies. The grey matter includes regions of the brain involved in muscle control, and sensory perception such as seeing and hearing, memory, emotions, speech, decision making, and self-control. These cells are responsible for the movement of muscles.
- The RDA is based, the ADA says, “on providing adequate glucose as the required fuel for the central nervous system without reliance on glucose production from ingested protein or fat.” Ah! So it's at least 130 grams of glucose per day that our brain needs!
- The brain typically gets most of its energy from oxygen-dependent metabolism of glucose (i.e., blood sugar), but ketones provide a major alternative source, together with contributions from medium chain fatty acids (caprylic and heptanoic acids), lactate, acetate, and possibly amino acids.
Updated: 25th November 2019