Sure, losing weight takes a lot of hard work, but it doesn't require resorting to extreme forms of dieting that deprive you of certain foods and nutrients. Celebrity fad diets are among the worst offenders-not only are they potentially dangerous to your health, but they're also ineffective in the long-term. So what is a fad diet, exactly? You know you have a fad diet on your hands when the buzzy plan is unrealistic and limits you to eating certain types of foods. Some fad diets might also encourage you to skip eating altogether and stick to drinking juices and teas instead (not safe, by the way). To help you avoid completely sabotaging your weight loss goals and choose the right diet for you, we consulted dietitians to share the top fad diets you need to ditch this year.