I found this easy recipe from "French Women Don't Get Fat" by Mireille Guiliano. According to Mireille, leeks are mild diuretic, and 48 hours or so of leek soup would provide immediate results to jump-start your diet. I'm going to try it this weekend and get back to you with my results.
Radical Leek Soup Recipe
2 lbs. leeks
Water to cover in a large pot
1. Clean leeks and rinse well to get rid of sand and soil. Cut end of green parts leaving all the white parts plus a suggestion of green. (Reserve the extra greens for soup stock.)
2. Put leeks in large pot and cover with water. Bring to boil and simmer with no lid for 20-30 minutes. Pour off the liquid and reserve. Place the leeks in a bowl.
The juice is to be drunk (reheated or room temperature to taste) every 2-3 hours, a cup at a time.
For meals or whenever hungry, have some of the leeks themselves, ½ cup at a time. Drizzle with a few drops of extra-virgin olive oil and lemon juice. Season sparingly with salt and pepper. Add chopped parsley if you wish.
NOTE: Although Mireille recommends using leek soup solely as your nourishment for 2 days, I do not recommend it. Eating like this slows your metabolism, thus decreases your chance at losing weight. I would incorporate this recipe as part of your well balanced diet. Bon Appetit!