Can you burn calories by thinking

Brainpower Although the average adult human brain weighs about 1. RMR varies from person to person depending on age, gender, size and health. If we assume an average resting metabolic rate of 1, calories, then the brain consumes of those calories just to keep things in order.

That's For comparison's sake, see Harvard's table of calories burned during different activities. Compared with most other organs, the brain is greedy; pitted against man-made electronics, it is astoundingly efficient. IBM's Watson, the supercomputer that defeated Jeopardy! Energy travels to the brain via blood vessels in the form of glucose, which is transported across the blood-brain barrier and used to produce adenosine triphosphate ATP , the main currency of chemical energy within cells.

Experiments with both animals and people have confirmed that when neurons in a particular brain region fire, local capillaries dilate to deliver more blood than usual, along with extra glucose and oxygen. This consistent response makes neuroimaging studies possible: functional magnetic resonance imaging fMRI depends on the unique magnetic properties of blood flowing to and from firing neurons. Research has also confirmed that once dilated blood vessels deliver extra glucose, brain cells lap it up.

Extending the logic of such findings, some scientists have proposed the following: if firing neurons require extra glucose, then especially challenging mental tasks should decrease glucose levels in the blood and, likewise, eating foods rich in sugars should improve performance on such tasks. Although quite a few studies have confirmed these predictions, the evidence as a whole is mixed and most of the changes in glucose levels range from the miniscule to the small.

In a study at Northumbria University, for example, volunteers that completed a series of verbal and numerical tasks showed a larger drop in blood glucose than people who just pressed a key repeatedly.

In the same study , a sugary drink improved performance on one of the tasks, but not the others. At Liverpool John Moores University volunteers performed two versions of the Stroop task , in which they had to identify the color of ink in which a word was printed, rather than reading the word itself: In one version, the words and colors matched—BLUE appeared in blue ink; in the tricky version, the word BLUE appeared in green or red ink.

Volunteers who performed the more challenging task showed bigger dips in blood glucose, which the researchers interpreted as a direct cause of greater mental effort.

Some studies have found that when people are not very good at a particular task, they exert more mental effort and use more glucose and that, likewise, the more skilled you are, the more efficient your brain is and the less glucose you need. Complicating matters, at least one study suggests the opposite —that more skillful brains recruit more energy.

Claude Messier of the University of Ottawa has reviewed many such studies. He remains unconvinced that any one cognitive task measurably changes glucose levels in the brain or blood. The base level is quite a lot of energy—even in slow-wave sleep with very little activity there is still a high baseline consumption of glucose.

For example, as you read this article, your body is using calories to support:. Your brain also uses energy to perform normal functions. Although it makes up 2 percent of your body weight, it burns 20 percent of the energy you consume.

In fact, your brain burns more energy at rest than a human thigh while running. Specifically, your brain gets energy from glucose.

Glucose comes from the food you eat. The glucose enters your bloodstream, then travels to your brain. Your nerve cells need ATP to communicate and carry out cognitive tasks.

When you mentally exert yourself, your brain uses more energy to do the task. To put things into perspective, a pound person burns about 23 calories per 30 minutes of sleep. Your brain performs the most basic functions during this time.

The same pound person burns about 42 calories in 30 minutes of reading while sitting. The increase in calorie burn is small.

You need to burn 3, calories to lose 1 pound. In 1 week, this equals out to calories a day. For example, as mentioned earlier, a pound person burns about 42 calories in 30 minutes of reading. This person would have to read for almost 6 hours to burn calories in a day. Granted, occasionally moving around will increase calorie burn per hour. Examples of brain exercises and their benefits include:. All brain workouts are not equal, though. And does that mean that thinking harder is a simple route to losing weight?

To delve into that question, we first need to understand how much energy is used up by a regular, non-chess-obsessed brain. That translates to or calories per day for the average woman or man, respectively. During childhood, the brain is even more ravenous. Boyer researches anatomical and physiological changes associated with primate origins. Humans aren't unique in this regard. Together with Duke University evolutionary anthropology graduate student Arianna Harrington, who studies energy usage in mammal brains, Boyer conducted research revealing that very small mammals such as the tiny tree shrew and the minuscule pygmy marmoset devote just as much of their body energy to the brain as humans do.

Boyer believes the reason is that despite brains being lightweight, human brains — and the similarly glucose-hungry brains in tree shrews and marmosets — are large relative to the rest of the body. Most of the energy hauled up by this organ is devoted to enabling neurons in the brain to communicate with each other, via chemical signals transmitted across cell structures called synapses, said Harrington. That involves a lot of transportation of ions across membranes, which is thought to be one of the most expensive processes in the brain.

Walking burns about four calories a minute. Kickboxing can burn a whopping ten calories a minute. Reading and pondering this article? That melts a respectable 1. Feel the burn but try the kickboxing if you're trying to lose weight. While 1. It's not all to your gray matter. Here's how it works: The brain is comprised of neurons, cells that communicate with other neurons and transmit messages to and from body tissues.

Neurons produce chemicals called neurotransmitters to relay their signals. PET scans have revealed your brain doesn't burn energy uniformly. The frontal lobe of your brain is where your thinking takes place, so if you are pondering life's big questions, like what to have for lunch to replace the calories you are burning, that part of your brain will need more glucose. Unfortunately, being a mathlete won't get you fit.

In part, that's because you still have to work muscles to earn that six-pack, and also because pondering the mysteries of the universe only burns twenty to fifty more calories per day compared with lounging by the pool. Most of the energy used by the brain goes toward keeping you alive. Whether you're thinking or not, your brain still controls breathing, digestion, and other essential activities. Like most biochemical systems, the brain's energy expenditure is a complex situation.