Practically every weight loss website out there has at least one (or one dozen) 1,200-calorie-a-day diet option. Even the National Institutes of Health has published a 1,200-calorie-a-day meal plan.

This involves replacing all foods with specially formulated products such as soups, shakes and cereal bars, providing between 800–1200 calories per day. Only follow a very low calorie diet if a ...