The Dilemma: It happens every time you buy groceries. Your bagger casually asks, “Paper or plastic?” And if you don’t answer within three seconds, people start looking at you funny. But it’s a complex question requiring considerable analysis. Which is better for the environment? Easier to carry? Less likely to be a choking hazard? You could stand in that grocery line all day.

People You Can Impress: It’s not about impressing anyone so much as not letting your indecisiveness aggravate the people in line behind you.

The Quick Trick: Plastic is probably better for the environment; paper is mostly better for the paper industry.

The Explanation:
First, let’s dispense with the difference between paper and plastic bags. Most plastic bags are derived from crude oil or natural gas by-products that have been treated to form long chains of carbon and hydrogen molecules. They’re then molded into the bag-with-handles shape we’ve known and loved at grocery stores since the mid-1980s. Paper bags, on the other hand, are made (you’ll never believe it) from trees—specifically, compressed wood pulp.

So which is better? We’ll begin with the case for plastic. For sheer ease of use, plastic certainly wins. Although the average paper grocery bag holds more than a plastic bag, plastic bags’ handles make them much easier to carry. Also, plastic bags are cheaper (which is why when you respond to the paper-or-plastic question with an ambivalent shrug, baggers are usually taught to pick plastic). Plastic bags also take up less landfill space. According to one study (and yes, there are studies about this sort of thing) two plastic bags take up 72 percent less landfill space than one paper bag.

Proponents of paper are likely to point out that paper is easier to recycle, that plastic is derived from a nonrenewable resource, and that plastic is nonbiodegradable. But as it happens, paper isn’t biodegradable either in modern American landfills, because landfills lack the water and soil needed for biodegrading. And it’s true that paper is easier to recycle (although plastic bags are recyclable), but recycling itself takes energy and creates pollution.

All in all, every study we found agreed plastic was the better bag, requiring less total energy to create and producing less waste than paper. Of course, the best solution is to use neither paper nor plastic. Instead, you could bring your own reusable bags to the grocery store. But that seems like an awful lot of work just to slightly increase the chances that your children can live on a habitable planet.

The Ugly Factor
The movie American Beauty makes the flying plastic bag into a pretty metaphor, but most of us would agree that plastic bags floating through the air aren’t so great. In South Africa, plastic bags came to be known as the “national flower” until 2004, when they were banned.