**This nerdy shirt from Shirt.Woot comes with the caption “Things are tough all over”**

In case you forgot from high school biology, ATP is the energy currency of the cell - most of what you metabolize eventually gets turned into ATP, and then ATP is used for just about everything in the cell, from moving your muscles to signaling. But I, being both a total nerd and a needless contrarian, started thinking: how much a gallon of ATP would *actually* cost? And I decided to find out.

I’ll preface my calculations by saying that every step is probably wrong, to a varying degree. Due to a combination of factors, such as my disinterest in biochemistry and the fact that the premise underlying all of my calculations is completely absurd, I can only give a ballpark answer to the above question, even though I’ll attempt to justify my assumptions.

Okay, let’s begin. Probably the simplest way to get ATP in your cells is to metabolize sugar. What has lots of sugar? Candy! I’ve decided we’re going to get our ATP from Reese’s, because I like Reese’s. Looking at the nutrition facts, two regular peanut butter cups contain 21 grams of sugar. Let’s assume that all of that sugar is in the form of glucose. Now, I know it isn’t all glucose; it’s also largely fructose (of *high fructose corn syrup* fame), but fructose is broken down into a molecule that enters the glucose metabolic pathway, which I understand already, so this is a reasonable assumption. Now, for every molecule of glucose that gets fully metabolized, a maximum of about 36 ATP are produced, if you’re going at maximum efficiency. I’ll assume that we get 30 ATP per glucose. In that case, we end up with 1774 grams of ATP after eating 1 pack of Reese’s.

Now it’s time to find out how many Reese’s you need to eat to get a gallon of ATP. ATP has a density essentially the same as water (a bit over 1 g/mL), so that makes our calculation easy - 1774 grams is the same as 1774 mL. The problem is, ATP is a solid (probably a crystal) at room temperature, and were you to heat it, it would decompose instead of melt. Therefore, we’ll have to suspend disbelief and pretend we have ATP in liquid form. Anyway, there are 3785 mL in a gallon, so to get that many mL of ATP, you would have to eat 2.1 packs of Reese’s, or 4 and 1/5 cups - surprisingly few!

Finally, we have to decide how much those Reese’s would cost. For this last part, I decided to shop where America shops: Walmart. Walmart sells a 6-pack of Reese’s (12 whole peanut butter cups!) for the amazing price of $3.94. Thus even if your metabolism is wildly ineffecient, you could produce a gallon of ATP for probably less than $2, and well less than the $4.47 from the shirt (the shirt also shows grades of ATP - if you could buy a gallon of something less than 100% ATP, it would cost less still).

So, the moral of the story is: don’t let Shirt.Woot’s fearmongering about ATP prices affect how you vote in the upcoming election.