Meal Replacements Boost Weight Loss

When added to a weight-loss eating plan, meal replacements reliably boost weight loss more than reduced-calorie diets that do not implement them, according to a review published in Obesity in 2011. Dieters who incorporate meal replacements lose an additional 5.5 pounds at the three-month mark and 5.2 extra pounds at 12 months than dieters who don't use them.

One reason meal replacements effectively boost weight loss is because they provide a set number of calories, so you know exactly how many calories you're getting. When preparing their own meals, dieters often underestimate the calorie content by roughly 40 to 50 percent, according to the Obesity review.

When it comes to meal replacements, bars keep you fuller longer than shakes. In men and women, meal-replacement bars kept participants full for about five hours, whereas shakes kept them full for roughly three hours, according to a study published in the International Journal of Food Sciences and Nutrition in May 2004.