5. The Cabbage Soup Diet
The Cabbage Soup Diet requires eating almost nothing but cabbage soup for a week or more. While low in calories, it’s also dangerously low in protein, healthy fats, and essential nutrients. This leads to rapid water weight loss — not sustainable fat loss. Side effects include bloating, weakness, and irritability. It’s an unsustainable crash diet that often leads to weight gain once normal eating resumes.