If the diet is a quick fix rather than one that promotes lasting lifestyle changes, this could pose a problem. In particular, extreme diets that promise big weight loss up front aren’t always sustainable — and you may end up overeating or even binge eating if you feel deprived. “Consider if the diet’s habits are ones you can continue throughout your lifetime, not just 21 or 30 days,” says Angie Asche, RD, a sports dietitian in Lincoln, Nebraska.


Safety: The history of dieting is filled with dangerous and downright life-threatening practices, from the fad of ingesting cotton balls to the infamous tapeworm diet. That's why, when looking for the best diet plan, nutritional balance and reduced caloric intake (usually 1,200 for women and 1,500 for men) are a must. After all, a diet is supposed to make you healthier, not make you sick.
To prep his patients for success, Dr. Seltzer tells them to plan around a large evening meal by eating a lighter breakfast and lunch—NBD since most people who eat a meal before bed tend to wake up feeling relatively full, he says. Research suggests balanced bedtime meals may also promote steady next-day blood sugar levels, which also helps with appetite regulation.
With its pre-packaged meals, portion-controlled menus, and strict caloric restrictions, the Nutrisystem meal delivery plan is ideal for people looking to lose weight fast without having to do any complicated meal planning. The company claims its 28-day program can help you lose up to 13 pounds by eating healthier versions of the foods you already love.

Based on the concept of caloric density, which states that some foods have few calories in proportion to their size (say, a lettuce), while others have lots of calories packed in small portions (a regular chocolate chip cookie comes to mind), Volumetrics divides foods into 4 categories based on their calorie/volume ratio, and is perfect for people looking to binge on some foods while still shedding pounds. However, as with the calorie counting approach, Volumetrics does not take into account the quality of the calories, prioritizing quantity instead. The app Noom and Weight Watchers (both reviewed above) share similarities with this diet theory.
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