How much energy does the brain take?

orenshani7

I work in IT as a service support person. My work includes various IT related tasks. Some do not require lots of thinking and concentrations, but others do. There are times, like in the last few days when I really have to concentrate and think, and I can feel as if my brain is shouting, "more fuel!". I know some of it is an emotional effect, but still, some of it is really increased demand.

So how much? Does anyone know how to calculate the numbers?

sijomial

Cut open skull, remove brain and weigh it, multiply by the numbers below.
(Death is a fairly significant side effect though. )

It is a significant contributor to your Resting Energy Expenditure but no it's not worth trying to calculate.

From https://bodyrecomposition.com/research-review/dissecting-the-energy-needs-of-the-body-research-review.html/

Deviette

Unfortunately the numbers are probably so small that they're essentially negligible.

The thing we forget is that our brain is always working, even if we're not setting it to a specific task, so even though we might feel like it's working much harder, it's just diverting it's processes to other things.

cmriverside

Well all I know is that if I'm under-fed for any length of time I have foggy thinking so I try to keep up with my meals and nutrition/macros/micros (as much as I can with the micros.) I feel significantly calmer and more able to focus with good nutrition, enough food and a bit of moderate exercise daily. Sort of using the machine as designed, so to speak.

AnnPT77

orenshani7 wrote: »

I work in IT as a service support person. My work includes various IT related tasks. Some do not require lots of thinking and concentrations, but others do. There are times, like in the last few days when I really have to concentrate and think, and I can feel as if my brain is shouting, "more fuel!". I know some of it is an emotional effect, but still, some of it is really increased demand.

So how much? Does anyone know how to calculate the numbers?

Thing is, even knowing the exact number wouldn't really help, because in a time of food inadequacy, your brain and the rest of your body will share the scarce resources in some way that's opaque to you, since both of them are needed to keep you alive.

If your calorie deficit is leaving you with brain fog, and you're already getting sound nutrition and adequate sleep, your body may be trying to tell you that it's time to take a maintenance break (if you've been at a deficit for quite a while) or increase your calorie level/decrease your deficit.

As someone who unintentionally underate for a while, got weak/fatigued, and took weeks to recover (even though I corrected immediately), I think it's important to heed early warning signs.

candythorns

I think the kind of food we eat helps. I also work in an IT Support role and when I get junk regularly I feel like I'm not on my toes as much as when I'm regularly healthy.

rsclause

I was reading this week about how fasting can increase mental clarity. It is thought that this is due to the brain switching to burning ketones. One passage commented on WWII prisoners who were being starved having such mental clarity that one prisoner was able to read a book from memory. Back to the OP's question is there any data or study that determines if brain energy consumption is static or goes up during intense thought?

apullum

Basic brain function is part of your BMR, and thinking hard burns at most an extra 50 calories per day according to this popular media source: https://io9.gizmodo.com/5920970/how-many-calories-does-thinking-burn

Granted, this is not a scientific article, but the story mentions articles that I can look for if folks are interested.

I would not add that extra 50 calories to your exercise log, since MFP has you set an activity level that is at least sedentary, and is not calculating your goal based on your BMR. You already get calories for doing normal activity, and hard thinking isn’t burning that many more.

Anecdotally, I started trying to lose weight in my first year of my postdoc, and have been maintaining during my time on the tenure track. I like to think I do a lot of thinking (although an obviously biased organ is telling me that), but thinking is not how I lost or maintain the weight loss.

rsclause

Now the question of the day is do kids playing video games count as using their brain at a higher level to get that extra 50 cal burn? Rhetorical question but I thought it would be funny if the thinkers and problem solvers here are actually using as much brain function as kids playing (mindless) video games.

Phoebe5164

It’s a very thought provoking question,
Hubbys diabetic and only counts net carbs to equal insulin amounts . I can tell you when he’s stressed or planning and calculating his blood sugar goes low as fast as when he’s working out .

It took me years to see his lows starting when his parents were over stressing us out 🤔

AnnPT77

rsclause wrote: »

Now the question of the day is do kids playing video games count as using their brain at a higher level to get that extra 50 cal burn? Rhetorical question but I thought it would be funny if the thinkers and problem solvers here are actually using as much brain function as kids playing (mindless) video games.

Who cares? 50 calories is maybe 5 or fewer Doritos - lost in the noise of calorie tracking. I'm willing to bet skateboarders/wakeboarders/snowboarders burn at least as many brain calories doing applied physics as video gamers do, plus the body ones.

Active braining > passive braining, every time.