This isn't rocket science. NONE of us have time to investigate the legitimacy of every conspiracy theory and claim out there. Best thing to do is find a reputable news source that is widely recognized as not being on the fringe, like MSNBC or Fox News. Personally, I go with Reuters and BBC for most of my news.
A good sign that they are reputable, without actually looking it up? The stories are a lot more boring, in general, than the distortions that the fringe media provides. Real news typically isn't very exciting or scary. If you're one of those people getting riled up by the news every day, you're probably listening to Fox, MSNBC, or something even worse.