The sacred heart diet is another of the ‘eat your fill’ diets, with the staple ingredient being a hearty vegetable soup. Named after the hospital where it was supposedly invented to treat overweight cardiology patients before surgery, it actually has no scientific credentials, with several hospitals even issuing statements disowning it. How Does The Sacred Heart Diet Work? The principle is to fill up on a very low calorie vegetable soup, which can be consumed in as large a quantity as is needed. Other foods are off limits, except for the foods prescribed for each day, as are alcoholic drinks and carbonated beverages. The diet lasts for seven days, after which time dieters are supposed to have lost at least 10 pounds, as well as feeling cleansed and rejuvenated.