The Onion Soup Diet

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The onion soup diet is kin to the more famous cabbage soup diet, which involves eating a cabbage- and onion-based soup as a staple food for a full week. As the soup is so low in calories, it encourages steady weight loss. However, the soup neglects to fulfill all nutritional needs, and the weight loss is not likely to be permanent.


For people who normally eat many processed and prepared foods, the onion soup diet plan may deliver more vitamins and minerals because it calls for so many fresh vegetables. According to MyPyramid, eating more vegetables and fruits can reduce risks of cancer, diabetes, stroke, heart disease, bone loss and kidney stones. For short-term weight loss, the onion soup diet often proves to be successful due to the very low calorie count it allows each day.


Although it can meet the objective of helping you lose weight, the onion soup diet is not a nutritionally sound or healthy way to do so. It doesn’t call for servings from every major food group and does not provide all essential nutrients that the body needs to function at its best. Additionally, the restrictive and limiting nature of the diet make it unsustainable in the long term, meaning that most of the weight it takes off is likely to come back on in a short period of time.


The onion soup diet calls for participants to eat the homemade, onion-based soup every day as their main meal item. details the rest of the instructions. On Day 1, fruit is also allowed, except for bananas. On Day 2, vegetables are permitted. Day 3 allows fruits and vegetables, and Day 4 also allows skim milk. Followers may eat tomatoes and some meat or fish on Day 5, beef and vegetables on Day 6 and brown rice, vegetables and fruit juice on the last day.


According to, the recipe for soup in the diet is based on a package of powdered onion soup mix. It includes one package of the mix, six green onions, two green bell peppers, a can of tomatoes, one bunch of celery, half a head of cabbage, a 48-ounce can of V8 vegetable juice and optional seasonings and bouillon.


The onion soup diet is not likely to cause long-term health problems, but if you try it along with other fad diets, it may negatively affect your metabolism and make it more difficult for you to lose weight in a safe and healthy way. Healthy weight loss involves regular exercise and balanced eating; the National Institutes of Health recommend whole grains, nonfat dairy, lean proteins, fruits and vegetables. Before beginning the onion soup diet or any related plan, speak with your doctor.