The 3-Day Diet: How Does It Work? The 3-Day Diet is a quick weight-loss diet that promises to help people lose 10 pounds in three days. “You follow a specific food plan for three days, then wait four to five days before starting again,” says Marisa Moore, RD, LD, a spokesperson for the American Dietetic Association. Supposedly, people can follow the low-calorie diet as often as they want. The 3-Day Diet details three days of low-calorie diet menus for breakfast, lunch, and dinner. “You’re supposed to be eating specific foods and the portions are controlled,” says Williams. Besides being severely low in calories, the diet is also low in carbohydrates and other nutrients. “As with most fad diet plans, there is a calorie restriction,” says Moore. The 3-Day Diet: Sample Diet The first day’s meals consist of: Breakfast Black coffee, tea, or water Half grapefruit Toast, 1 slice Peanut butter, 1 tablespoon Lunch Canned tuna, ½ cup Toast, 1 slice Black coffee, tea, or water Dinner 2 frankfurters Carrots, ½ cup Broccoli, 1 cup Vanilla ice cream, ½ cup Black coffee, tea, or water The 3-Day Diet: Pros and Cons Moore and Williams found few benefits in the 3-Day Diet. “Compared to other fad diets, this one does include some fruits and vegetables, but I’m leery about saying there is any positive to this diet,” says Moore. “Relatively speaking, at least this diet doesn’t lead to high fat and high sugar intake, but I still wouldn’t recommend it.” The list of cons is long: The 3-Day Diet leads to the wrong kind of weight loss. “You’re going to lose weight on this plan, but what kind of weight are you losing?,” says Williams. “When you restrict calories, the body compensates by slowing down metabolism and going into starvation mode, losing lean muscle and conserving fat. Then, when you eat normally again, the body reacts by continuing to store the calories as fat as a form of protection because it doesn’t know when the starvation might happen again.” You’re likely to be hungry, cranky, and constipated. Most people need 25 to 30 grams of fiber a day, says Williams. Under the 3-Day Diet plan, however, people only get about 2 to 5 grams at breakfast and lunch and a little more than that at dinner. “The lack of fiber, combined with the plan not providing enough water, can lead to constipation,” says Williams. There is a lack of science. There is no research behind the recommendations in the 3-Day Diet. “There is no scientific basis for the foods that are chosen,” says Moore. The 3-Day Diet skimps on nutrients. “It’s a restrictive plan that’s lacking a variety of nutrients,” says Moore. The 3-Day Diet: Short- and Long-Term Effects In the short term, you will achieve quick weight loss under the 3-Day Diet. “It’s fairly easy for people to lose weight — you can do that when you just urinate, but you want long-term, sustainable weight management,” says Williams. The 3-Day Diet lacks any sort of long-term tools. “It doesn’t teach lifelong lifestyle changes such as eating habits, behavioral changes, or exercise,” says Moore. “With any healthy eating plan, physical activity and mental wellness should be included.” More problematic, the 3-Day Diet actually encourages a disordered eating pattern and a yo-yo dieting effect. “It sets you up to eat more on the off days,” says Moore. “It’s a recipe for the vicious cycle of yo-yo dieting.”
