You probably had some palm oil today. If it wasn't in your toothpaste, or your shampoo, it was in the margarine you had at breakfast. Found in roughly half of the products sold in modern supermarkets, it's the world's most popular edible oil.
It's also the cause of one of the world's biggest environmental catastrophes, the decimation of southeast Asia's rainforests. Indonesia has lost enough rainforest to palm plantations since 1967 to cover the entire state of Kentucky. And that's not just horrible for Indonesia.
The typical method for clearing rainforests in Southeast Asia is to burn them to the ground, which releases vast quantities of the greenhouse gases that cause global warming. According to one peer-reviewed study, the rainforests burned in 2010 in just one Indonesian state produced the same carbon emissions as 28 million cars.