Food grown far away has to ride to you on pollution-belching trucks or ships or coal-fired bulldozers, all of which result in carbon dioxide entering the atmosphere. Consequently, the theory goes, we can dramatically reduce the environmental impact of what we eat by buying food grown locally. That's sort of true, although don't look surprised when I tell you there's a "but."

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Sure.

The "but" is that it takes a lot more carbon to simply grow the food, with production accounting for something like 83 percent of the total carbon footprint. This means that a farm that's even slightly more efficient at growing might be the better choice, even if it's farther away. For example, if you're buying lamb in the U.K., one study has calculated that it's four times more carbon intensive to buy locally grown lamb than lamb shipped all the way from New Zealand. That study was admittedly performed by a New Zealand university, which might not be entirely unbiased on the subject of lamb exports, but the same thing has been found in a lot of other cases as well.

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Pictured: A New Zealand university.

Also, these "food mile" calculations elevate carbon dioxide above all other pollutants and environmental impacts. A full life-cycle consideration of the environmental impacts of food might reveal a dramatically different conclusion from "local food is better." But seeing as that kind of spreadsheet heavy-nerd-lifting is the kind of thing people don't want to do in a grocery store, here's a super simple shorthand trick you can use to reduce the environmental impact of your food:

Waste less food.

Something like 40 percent of the food we grow isn't eaten, the vast majority of that because it's thrown away by the consumer. As long as you eat everything you buy, you'll be way ahead of the guy buying local produce and letting it spoil. So eat your leftovers, kids, and please be sensible when buying food in bulk.

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If you're buying 30 burritos at Costco, you'd goddamned better be prepared to saddle up and eat 30 burritos, partner.

This is called "downcycling," and it's a big problem in the recycling world, which means a huge amount of the recyclable products we buy are still made with virgin raw materials. Paper has a similar problem; it recycles fairly easily, but that process chops up the fibers that give paper its texture, and recycled paper never feels as smooth or high quality as the fresh stuff.

It's not all bad, though. We have plenty of use for not-very-smooth-feeling paper in our packing materials and cheap napkins and such. And some recyclables recycle up real nice. Aluminum cans, for example, can be turned into fresh aluminum cans with no quality problems at all, using 5 percent of the energy required to make new cans. So please don't stop recycling. Because ...

And that's all if you have an existing landfill. If you want to build a new one, you're looking at years of design and engineering and the small matter that no one wants a landfill anywhere near them, and as soon as you propose the location for a new one, everyone around it will flip their shit.

But let's say our arguer knows that and still says recycling is too expensive (they're not wrong -- landfilling is up to 50 percent the price of recycling). Even then the comparison isn't clean, as it has to account for the fact that recyclables can be sold and the wildly fluctuating market value of those recyclables, as well as the total life-cycle cost of building new products and landfilling them vs. partially recycling them. For example, those plastic bottles we discussed earlier that get recycled into crappy lawn furniture? Well, if we weren't making that lawn furniture out of plastic bottles, we'd be making it out of oil (that's what plastic is, kids), and as you might have heard, that hasn't been getting cheaper. Yes, we should probably be buying less crappy lawn furniture, but while we're not, these total life-cycle calculations make recycling far from a pointless activity.

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Although it will cost some falcons their jobs.

So with all of these probable poisons pressed up in our guts, it's no wonder cancer cases are climbing steadily:

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Even when we turn that into a cancer rate to account for our growing population, the rates are still climbing:

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But when we correct the statistics to account for the fact that we have a lot more older people around now, cancer rates are basically flat:

Google

So what's the deal? Well, it's a couple things. First, the number one risk factor for cancer is age, which seems obvious. The older you get, the more carcinogens you're exposed to, and the greater your risk of cancer. So, because we're living longer on account of the fact that we know about penicillin and insulin now, we're going to see more cancer. Today's cancer victim was last century's heart disease victim. Additionally, cancer can be caused by no carcinogens at all, simply from cells messing up when they reproduce, or by the everyday background radiation that is a side effect of living in this bullshit universe. Some researchers claim that if we lived long enough, everyone would get cancer; it's an almost inevitable side effect of bodies that are made up of endlessly reproducing cells.

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Sure.

This isn't giving you license to start cramming pollutants into your gullet; those definitely increase the risk of cancer, and although the overall rate is flattish, some specific cancer rates are going way, way up. But on the whole, this isn't some plague of the modern era, the world now paying for mankind's sins. So long as you minimize your exposure to cigarette smoke, or radiation, or barbecued meat, I wouldn't sweat it too much.

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Wait? What? Fuck you.