The thought began: “How many calories are in a gallon of gasoline?”. Then the social experiments. Then the blog post.
Sometimes I walk to work.
And sometimes when I walk to work I ask people if they drove to work.
If they say ‘yes’, then I tell them that I walked to work and then ask how long their commute was. [The answer to this question is irrelevant, but is instead meant to shape the answer to my next question].
Finally, I ask them who they think burned more calories (to be precise, I should say ‘kilo-calorie’) on the way to work. Me walking or them driving?
Of course this is a trick question, as asking about calorie burning is a measurement typically applied to physical fitness and not in the consumption/efficiency of automobiles. The correct answer is that my coworker who drove to work burned more calories.
Why? Because while I may have burned a mere 85 calories per mile to get to work, the highest efficiency non-hybrid commercial automobiles burn the equivalent of 775 calories per mile under the best conditions [true nerds can find math/assumptions at bottom of post]. Almost 10x more than walking. Your car gets its daily work-out in before you’ve even started thinking about your workout.
The bright side to this is that it is actually cheaper to power your car than it is to power your body. You can buy 31,000 calories from your local gas station for $3.51, but to get 31,000 in Spam, you would need to spend $95.01 on 30 cans of Spam (Amazon has a 6-pack available for $19.20). I don’t know if Spam is the least expensive food per calorie, but it is well known to be extremely calorie-dense. Gasoline is 27x more efficient per dollar than Spam.
At this point most people like to remind me that you can’t eat gasoline (although it may explains some things if I had at some point). Only cars can ingest liquefied dinosaur remains. Sadly, and despite this fact, our car engines are at best converting those calories into productive work (moving those wheels) at around 20% efficiency, while our human bodies digesting, say – a potato, operates closer to 40% efficiency.
So what’s the point?
There are three points actually:
If you had to power your car strictly with the effort you can expend with your human body, you would have an appreciation for just how much work those dead dinosaurs do for us, and how cheap they do it for. To get the energy of one gallon of gasoline, I would need to run for almost 5 hours straight.
There are 3,500 calories per pound of fat. This means that if you are 9 pounds or more overweight, then you are carrying around at least 1 gallon’s worth of calories. Most people are overweight because they spend too much money on eating food, and even more money on gasoline so they don’t have to expend the calories in that food. A bit ironic isn’t it?
Gasoline is still cheap for the amount of work it does in a short time span, but healthy food is amazingly expensive. Is this a result of the laws of nature or the laws of our nation?
 Using KIA Rio’s 2012 Highway MPG of 40MPG, and average calorie count per gallon of gasoline (31,000): 31,000 / 40 = 775
 As of 6/17, current Avg. Price of gasoline is $3.51 according to AAA on: http://fuelgaugereport.aaa.com/?redirectto=http://fuelgaugereport.opisnet.com/index.asp
 2oz @ 174 calories * 6 (to get calories per can) = 1,044 calories in one can. Amazon has 6-pack for $19.20 so divide by 6 to = $3.20
 Technically this is a flawed comparison because our bodies are not combustion engines and are therefore governed by a different system of equations than a car.