1. Diet fads may be doing more harm than good. In a bid to clear up the confusion over what is and isn't healthy, researchers examined 25 studies involving tens of thousands of participants. They found that many of the latest nutritional trends involve significant health risks: Coconut oil is high in artery-clogging saturated fat; juicing concentrates sugars and makes it easier to consume too many calories; and many gluten-free foods are high in processed carbohydrates, which are linked to a higher risk for type 2 diabetes.