Dear Umbra,

My name’s Jon and I’m a diet pop addict. My diet right now is 70-80 percent local, organic, or both, but I just can’t help myself when it comes to getting my fix. I drink several 20-ouncers a day of diet and just can’t seem to stop. Is my habit hurting the earth? Common sense says that water from my stainless steel canteen is a whole lot better than chemicals from a plastic bottle, but my addict brain is grasping at straws, hoping that diet pop is one of those rare exceptions.

Jon B.
Lakewood, Ohio

Dearest Jon,

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As you no doubt know, your question is funny, and the answer is: Of course your processed beverage and its container have an environmental impact. Plus, it’s gotta be horrible for you. The ingredients were made in a lab, and I’m not sure the new fortified Coke or Pepsi diet sodas (Niacin! B vitamins! Chromium!) will close the nutrient gap. Several countries and at least one American state have tried to ban aspartame, that pop-ular artificial sweetener. Health isn’t my bailiwick, though. I get to ignore your teeth, intestines, and major organs and focus on the planet.

Aspartame the beast.


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Is your habit hurting the earth? Sure — the manufacturing process for the chemicals (synthetics and “natural flavors,” anyone?) all have emissions impacts. But more on the carbon footprint of soda ingredients in a moment — first we must speak of Coke and water. I use Coca-Cola as a whipping boy (er, representative example) because there is ample documentation about how the soda giant operates.

Water is the primary ingredient in all Coke products, and a major component of pop-making in general. Each liter of a Coke product requires approximately 2.5 liters of H20 — and that’s just at the bottling plant. In 2006, for example, Coca-Cola apparently sucked up about 80 billion gallons of water for use in its drinks, for growing the ingredients, and for general manufacturing uses. The mildest thing we can say about your addiction in this context is that it wastes water. A harsher comment might be: You are actively complicit in global corporate water hogging, stealing a scarce resource from impoverished communities.

We can also get a little extrapolative climate change information on your addiction from our new toy, the Carnegie Mellon Green Design Institute’s Economic Input-Output Life Cycle Assessment model. Remember, EIO-LCA is an online tool that calculates the overall environmental impact of producing certain dollar amounts of various products. In this case, we click on the “food, beverage, and tobacco” industry, then choose “soft drink and ice manufacturing,” which, the model reveals, involves power generation, grain farming, wet corn milling, trucking, aluminum production, paper mills, oil and gas extraction, and more. Forgive my ignorance — do you spend somewhere in the dollar-and-change range on those 20-ounce plastic bottles? If so, and if “several” per day means three, you’re drinking more than $1,000 retail per year, which must be at least $500 worth of wholesale soda per year. For each $500 of economic activity in wholesale soft drink and ice manufacturing, 0.439 metric tons of CO2 equivalent are released. Given those very approximate numbers, and leaving lots of wiggle room to account for variations in soda brands, your fizz fixes emit maybe half a ton of CO2 equivalent a year. To what is this comparable? Flying round trip from Cleveland to New York City.

As to the packaging, I sweetly refer you to the many discussions in this space about the importance of reusable vessels over disposable (search Grist for “plastic bottle” and prepare to be rewarded). Yes, your stainless steel canteen, used many times, is better than a single-use plastic bottle. And it’s certainly better than virgin aluminum — gadzooks. In sum, as we already knew, your diet soda habit is not remotely compatible with the rest of your organic, local food lifestyle. You alone can decide if the impact of the addiction is acceptable to you and by extension to your fellow earthlings. Water also has a large advantage over diet drinks: It is good for you. In fact, you can’t live without it.


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