Harmful: Not the kind of word that makes you want to throw a party or start a book club. But in the context of trends, harmful is actually kind of exciting (in a scary, doom-and-gloom sort of way). These are the things we're doing, searching for, and talking about that could be causing serious damage to our planet and ourselves. From environmental degradation to crop production, this category is all about the choices we're making (or not making) and their consequences. Some trends are more obvious – clearcutting, anyone? – but others require a little more thought. Take healthy gut, for example. Sounds good, right? Except that the way we're trying to achieve it might be doing more harm than good. And then there's cultural influence, which can be positive or negative depending on how it's wielded. The bottom line? Harmful trends are the ones we need to pay attention to, because they have the potential to shape our future in some pretty scary ways.