Assuming you will recycle the container, there are many reasons why aluminum cans are better than both glass and plastic bottles: Making them requires less energy; they are more commonly recycled; and they are typically made from 40 percent recycled aluminum.

Aluminum cans require about 30 percent less energy to make than either glass or plastic bottles. And about 45 percent of cans are recycled, compared with 34 percent of plastic bottles and only 25 percent of glass bottles. Also, at 40 percent, cans have the most post-consumer recycled content. Glass bottles have about 26 percent recycled content, and plastic bottles have none at all. Plastic bottles can’t be recycled into more plastic bottles—they have to be downcycled, which means they get turned into a product that is made with lower-grade plastic.

The high proportion of recycled material in cans explains why they are so energy-efficient to produce: Making cans from recycled aluminum requires significantly less energy than making them from virgin ore. Cans produced from solely virgin aluminum require nearly 50 percent more energy per can. If cans could be made completely with recycled aluminum, the manufacturing energy needed would decrease by more than 70 percent per can.

This link between recycled content and energy savings is the reason you might have heard that recycling saves energy. When you recycle one 14.3-gram aluminum can, you eliminate the need to produce an additional 14.3 grams of virgin aluminum, which saves about 1,150 Btus—enough energy to run a 100-watt light bulb for more than 3 hours.

Although the production of plastic bottles uses slightly less energy than the production of glass bottles, glass is actually your next-best choice. Glass is fully recyclable, and glass bottles at least have the potential to contain up to 100 percent recycled material, though they rarely do. And even plastic bottles that get downcycled are typically reincarnated only once before they’re sent to the landfill.—Colleen Howell