The HCG diet requires you to follow a strict diet plan, drastically cutting your caloric intake, in addition to taking the hormone supplements. You can have a few servings of vegetables each day, but the diet plan limits your selection of veggies. Before beginning the HCG diet, meet with your health care provider to ensure it is a good fit for you, as the jury is still out on its safety and effectiveness. A review in the May 2013 issue of "The Annals of Pharmacology" reports that the HCG diet has not been adequately studied for safety and may be responsible for adverse effects, such as deep vein thrombosis.

HCG is short for human chorionic gonadotropin, a hormone women produce in the placenta during pregnancy. This diet plan is broken up into three separate phases. In the initial loading phase, which lasts for two days, you can follow your normal diet regime, thus stock up on fat stores. The main part of the diet is the maintenance phase, lasting for anywhere from 21 to 40 days, depending on your weight loss goals, according to GreenHCG.com. During maintenance, you have to limit your caloric intake to no more than 500 total calories. Lastly, the stabilization phase allows you to slowly start increasing your caloric intake over a period of three weeks.

Generally, vegetables fit into one of two different categories: starchy and nonstarchy. Starchy vegetables have a higher starch content, providing more carbohydrates and more calories. The HCG diet plan includes a few types of nonstarchy vegetables, which provide minimal amounts of starch and calories. Enjoy nonstarchy varieties including Swiss chard, tomatoes, spinach, red radishes, salad greens, fennel, onions, asparagus, cabbage or cucumbers. While you can have nonstarchy vegetables on the HCG diet plan, you have to limit your servings and measure them carefully to avoid consuming too many calories.

Breakfast on the HCG diet typically consists of a cup of plain coffee or tea. You can sweeten your morning brew with an artificial sweetener and add in a tablespoon of milk, but you must limit your dairy consumption to 1 tablespoon every 24 hours. Lunch and dinner are similar, including 100 grams, or about 3 1/2 ounces, of meat, a cracker, and a serving of fruit and vegetables. You may experience some weight loss while eating this way, but it most likely stems from the minimal calories you consume.

Nonstarchy vegetables from the approved list offer a minimal 25 calories per 1 cup raw or 1/2 cup cooked serving, according to the American Dietetic Association. Enjoying a small portion of lean meat alongside sauteed spinach provides less than 190 calories. While nonstarchy veggies are naturally low in calories, you have to limit your intake to one serving at lunch and one serving at dinner to fit into the 500-calorie diet plan.