The Master Cleanse Popularized by Beyonce, who used it to lose weight for Dream Girls, the Master Cleanse involves drinking a mixture of lemon juice, syrup, cayenne pepper and water between 6 and 12 times a day. Sure, you’ll lose weight initially, but unsustainable diets like this one almost always lead to rapid weight gain once your body starts demanding nutrients again. The Military Diet According to the Military Diet, you should restrict your caloric intake to around 1,200 for 3 days, then return to regular eating for 4, opting for fat and protein while avoiding carbs. But consuming so few calories can send your body into starvation mode, which actually slows your metabolism down. When you return to regular eating, you’ll actually gain weight much faster as a result. The Baby Food Diet This diet encourages people to replace breakfast and lunch with 14 jars of baby food, which simply doesn’t contain proper nutrition for adults. It’s not possible to maintain good health while sustaining yourself on food meant for infants. The Five Bite Diet Although developed by a medical professional (Dr. Alwin Lewis), this diet is dangerous for a number of reasons. First, it involves skipping breakfast, which is the most vital meal of the day as it kick starts metabolism and gives the body and brain a much-needed energy boost. Second, it limits practitioners to 5 bites of lunch and 5 bites of dinner, which simply does not yield enough calories to sustain healthy functioning. The Five Bite Diet also doesn’t place any emphasis on the kinds of foods you should be eating, attributing the same value to a bite of cake as it does to a bite of salmon or apple. The Werewolf Diet Practitioners of the Werewolf Diet ingest only water and fruit juice for 24 hours during the full and new moon. People who participate are likely to regain any weight they lose soon after, as losing weight and keeping it off means establishing good daily habits rather than crash dieting twice a month. The Grapefruit Diet Good health requires eating a variety of foods. Avoid any diet based around eating just one. The Grapefruit Diet, wherein you eat only grapefruit for 10 to 12 days, puts you at risk because fruit doesn’t offer nearly enough protein to sustain you. Like many of these fad diets, you may lose weight at first, but you’ll gain it all back once you return to regular eating habits.