How many calories are in a human brain

August 7, 2009 8:31 AM

How many calories are in the average human brain? As in, if you were to eat a brain zombie style, how many calories would that represent?
posted by KirTakat to health & fitness (17 comments total)

The average human brain weighs 1,300 - 1,400 grams. Beef brain is 590 calories per serving which is 391 grams. The average brain is approximately 3.5 servings. Thus 2065 calories.
posted by jessamyn at 8:36 AM on August 7 [23 favorites]

One gram of protein is 4 calories.

The average weight of a human brain is 1.36 kilograms.

Blech; is brain protein?
posted by Houstonian at 8:36 AM on August 7

You could probably start with the brains of other animals used in cuisine.

Here, for instance.
posted by hellboundforcheddar at 8:37 AM on August 7

Awesome, thanks Jessamyn
posted by KirTakat at 8:44 AM on August 7

One gram of protein is 4 calories.

The average weight of a human brain is 1.36 kilograms.

Blech; is brain protein?

As Jessamyn's answer reflects, brain is mostly water. After that, protein and fat.
posted by grobstein at 8:46 AM on August 7

Also, 391g of beef brains contains -12000- mg of cholesterol.
See? Hearts and mind don't mix.
posted by Cat Pie Hurts at 8:51 AM on August 7 [9 favorites]

Note also that a standard serving of beef brain has approximately 12,000 mg of cholesterol - that's 4000% of your RDA; so a 1,350 gram brain would provide about 14,000 % of RDA. Wow.
posted by buxtonbluecat at 8:53 AM on August 7

Unless a large part of the brain is indigestible, 590 calories for 391 grams of beef brain seems low. The wikipedia page on brain as food puts the fat content of a brain at about 60% due to mylenation. Even 50% of 391 grams is roughly 200 * 9 = 1800 calories, far more than the nutritional content that jessamyn reported.

Assuming 60% fat and 40% protein and high digestibility, a 1300 gram brain would have around 9000 calories.

Dietary cholesterol has little influence upon total cholesterol levels, whole health source uses some data from the framingham heart study to back up this point.
posted by zentrification at 9:34 AM on August 7 [1 favorite]

it sounds like your average stumbling zombie needs less than 1 brain/ day to keep from starving to dea... oh, wait...
posted by hellboundforcheddar at 9:57 AM on August 7 [1 favorite]

Assuming 60% fat and 40% protein and high digestibility, a 1300 gram brain would have around 9000 calories.

Might I suggest that you are forgetting water? I think the brain is wet. See my scintillating comment above.
posted by grobstein at 10:00 AM on August 7 [1 favorite]

I think jessamyn is correct, because as pointed out, lots of the brain is water. To extrapolate further from jessamyn's answer- we can use what we know about the differences between cow and human brain tissue to adjust from the ballpark of 2065 calories.

Human brain has a slightly different density and composition than cow brain. Cow axons are more myelinated than human brain, because as this Princeton lecture points out, myelination increases with brain volume because the axons are longer. We might expect that the cow brain has a higher % lipid per gram, and thus a higher caloric value, since lipids have more calories per gram than protein, and myelin is mostly lipid

However, as this abstract points out, total neuron density gets lower with increasing brain volume, so while cow neurons are fattier, there are less of them per unit volume, so perhaps the greater density of neurons in human brain also changes our estimate of the nutritional content. The grey to white matter ratio would be higher in humans, and from the second link, we know grey matter is leaner. That doesn't tell us that there are necessarily less calories per gram overall, but it does tell us that there would be fewer calories from fat per gram.

This also didn't take the cerebro-spinal fluid, the meninges, blood, or other possibly edible parts of the brain into account.

Nonetheless, if you're a zombie who's worried about your saturated fat intake, I would recommend human brain over cow brain.
posted by slow graffiti at 10:27 AM on August 7 [6 favorites]

I can't believe I'm weighing (ugh) in on this, but we're not comparing apples to apples (or brains to brains) here, which is leading to some confusion. Jessamyn links no source for her data, but the sources that are linked all report calories in a single serving of cooked beef brains. I assume Jessamyn's does too, though maybe not. (Cow brain sushi? Hellooooooo BSE!)

Anyway, cooking would presumably remove some of the liquid and thus result in a different calorie/gram calculation from that for raw ("zombie style") brains. Yes, a human brain is wet and heavy, but the question would be what is its cooked weight, as the water presumably has no caloric content. Weight-watching, raw-brain eating zombies want to know! (And don't have AskMe accounts).
posted by The Bellman at 11:37 AM on August 7

Raw beef brain- 162 calories per 116g serving
Simmered beef brain- 590 calories per 391g serving
posted by slow graffiti at 11:51 AM on August 7

So, 1.4 cal/g raw, 1.5 cal/g cooked. More energy density cooked, but nowhere near as much more as I would have guessed. Learn something new and utterly useless everyday.
posted by The Bellman at 12:17 PM on August 7

I hope this for a book you're writing.
posted by small_ruminant at 12:31 PM on August 7 [2 favorites]

Nonetheless, if you're a zombie who's worried about your saturated fat intake

I don't believe the undead need to worry about cardiovascular disease the same way the living do.

In fairness, even if you're among the living in a world in which zombies exist, cardiovascular disease might be fairly low on your list of concerns.
posted by DevilsAdvocate at 12:42 PM on August 7 [1 favorite]

(Cow brain sushi? Hellooooooo BSE!)

Might as well go for the sushi -- prions are resistant to inactivation by heat...cooking those brains doesn't guarantee safety! You could drain off some of the fats that would melt though...
posted by Tandem Affinity at 12:54 PM on August 7