# does thinking make you hungry? **URL:** \ **Category:** Factual Questions\ **Created:** [March 25, 2000, 5:18am UTC](https://boards.straightdope.com/t/does-thinking-make-you-hungry/9160 "2000-03-25T05:18:00Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![scr4](https://avatars.discourse-cdn.com/v4/letter/s/59ef9b/32.png) [@scr4](https://boards.straightdope.com/u/scr4)\ **Post date:** [March 25, 2000, 5:18am UTC](https://boards.straightdope.com/t/does-thinking-make-you-hungry/9160/1 "2000-03-25T05:18:00Z")
Something I always wondered about: does the amount of energy used by the brain depend on how hard you are thinking? It seems that if I spend a really productive day of studying or mental work, I get more hungry than if I had loafed around watching TV. However it may just be psychological. Does anyone know? Surely someone out there has measured the amount of oxygen consumption for different sedentary activities? ---
**Author:** ![Steve-o](https://avatars.discourse-cdn.com/v4/letter/s/ecc23a/32.png) [@Steve-o](https://boards.straightdope.com/u/Steve-o)\ **Post date:** [March 25, 2000, 6:11am UTC](https://boards.straightdope.com/t/does-thinking-make-you-hungry/9160/2 "2000-03-25T06:11:00Z")
Hmmmm… Let’s see… Let me think… What should I have for dinner… (burgers? pizza? tacos? lasagna?) Damn I’m hungry. Yup… thinking definitely makes you hungry 😛 * * * Things are random only insofar as we don’t understand them. ---
**Author:** ![sailor](https://avatars.discourse-cdn.com/v4/letter/s/a587f6/32.png) [@sailor](https://boards.straightdope.com/u/sailor)\ **Post date:** [March 25, 2000, 9:10am UTC](https://boards.straightdope.com/t/does-thinking-make-you-hungry/9160/3 "2000-03-25T09:10:00Z")
I once saw a documentary dealing with exactly this issue but I do not remember it well. I do remembeer it concluded that the brain consumes a disproportionate amount of energy in the form of sugar and I believe this does go up with brain activity. I have a friend who went on a low carbohydrate diet and I have the feeling he is getting dumber. I keep asking myself if it could be that his brain is starved of the necessary fuel (but I have not shared this thought with him as I do not need any more enemies). Maybe he would be getting dumber anyway… ---
**Author:** ![Andy](https://avatars.discourse-cdn.com/v4/letter/a/aeb1de/32.png) [@Andy](https://boards.straightdope.com/u/Andy)\ **Post date:** [March 25, 2000, 5:41pm UTC](https://boards.straightdope.com/t/does-thinking-make-you-hungry/9160/4 "2000-03-25T17:41:00Z")
Some time ago I got some info on this. The study involved looking at metabolism and the brain and concluded, through oxygen uptake analysis, that high mental activity produced a small, but measurable, increase in oxygen consumption. ---
**Author:** ![ASPA](https://avatars.discourse-cdn.com/v4/letter/a/b19c9b/32.png) [@ASPA](https://boards.straightdope.com/u/ASPA)\ **Post date:** [March 25, 2000, 8:27pm UTC](https://boards.straightdope.com/t/does-thinking-make-you-hungry/9160/5 "2000-03-25T20:27:00Z")
> [@](#): > > Originally posted by scr4: > \*\*Something I always wondered about: does the amount of energy used by the brain depend on how hard you are thinking? It seems that if I spend a really productive day of studying or mental work, I get more hungry than if I had loafed around watching TV. However it may just be psychological. Does anyone know? Surely someone out there has measured the amount of oxygen consumption for different sedentary activities? \*\* ((()))) Someone has, indeed. Here’s a formula: AOC / CXSA1 x (CXSA2 - CXSA1) = OT. ---
**Author:** ![Alphagene](https://avatars.discourse-cdn.com/v4/letter/a/8e7dd6/32.png) [@Alphagene](https://boards.straightdope.com/u/Alphagene)\ **Post date:** [March 25, 2000, 8:44pm UTC](https://boards.straightdope.com/t/does-thinking-make-you-hungry/9160/6 "2000-03-25T20:44:00Z")
I’m no neurologist, but AFAIK all brain activity uses nutrients and thus will ultimately increase your hunger. Brain activity is not just limited to “thinking” in the deep cognitive sense. Reading a newspaper taxes the brain but it’s not really considered deep cognitive thought. Especially if it’s the _New York Post_. Does your brain use more energy pondering Hawking radiation than you do processing the television image of Kenny’s corpse getting eaten by rats? I doubt it, but if you do, it’s not by much. What separates the two is the parts of the brain that are active, not the amount of fuel-burning that your brain does. As far as overall nutrient usage, I don’t think there is much of a difference between a brain thinking “Aren’t Gaussian equations fundamentally flawed due to their reliance on a strictly Euclidan view of the universe?” and a brain thinking “Who farted?” * * * **Gypsy** : Tom, I don’t get you. **Tom Servo** : Nobody does. I’m the wind, baby. ---
**Author:** ![ASPA](https://avatars.discourse-cdn.com/v4/letter/a/b19c9b/32.png) [@ASPA](https://boards.straightdope.com/u/ASPA)\ **Post date:** [March 25, 2000, 10:43pm UTC](https://boards.straightdope.com/t/does-thinking-make-you-hungry/9160/7 "2000-03-25T22:43:00Z")
> [@](#): > > Originally posted by Alphagene: > \*\*…all brain activity uses nutrients and thus will ultimately increase your hunger. Brain activity is not just limited to “thinking” … “Who farted?” > > \*\* I understand from another post that when on the elevator one must stand to one side and pass on the other. Here, we pass anywhere. But to directly answer the question, ‘It wasn’t me.’ Now, on to your real point: Based on your information, to the formula given some posts above should a few "N"s should be added for nutritive value. ---
**Author:** ![funneefarmer](https://avatars.discourse-cdn.com/v4/letter/f/9fc348/32.png) [@funneefarmer](https://boards.straightdope.com/u/funneefarmer)\ **Post date:** [March 25, 2000, 10:59pm UTC](https://boards.straightdope.com/t/does-thinking-make-you-hungry/9160/8 "2000-03-25T22:59:00Z")
[Basal Metabolic Rates in Infants](http://www.unu.edu/unupress/food2/uid09e/uid09e0e.htm) Lots of information and tables on the amount of energy used by the brain and other organs in infants and how it compares to use through maturity. Includes tables breaking it down by weight of the individual organ. > [@](#): > > The contribution of the brain to basal metabolism is exceptionally high in the newborn period (87%) and throughout the first year of life (53 to 64%) (HOLLIDAY, 1986) (Table 1). Two basic biochemical processes, protein synthesis and ion pumping, are estimated to account for 2/3 or more of basal metabolism (GRANDE, 1980). The energy consumed by the brain primarily supports active transport of ions to sustain and restore membrane potentials discharged during the process of excitation and conduction. ---
**Author:** ![Arjuna34](https://avatars.discourse-cdn.com/v4/letter/a/eb8c5e/32.png) [@Arjuna34](https://boards.straightdope.com/u/Arjuna34)\ **Post date:** [March 26, 2000, 3:40am UTC](https://boards.straightdope.com/t/does-thinking-make-you-hungry/9160/9 "2000-03-26T03:40:00Z")
Although heavy thinking in itself doesn’t consume much more energy than “light” thinking, typically if you’re thinking hard about something, your entire body is more tense, stressed, etc. when you’re thinking hard about something. Thise tensing of muscles uses up more calories and causes bodily tiredness, not the heaving thinking. Arjuna34