How many servings of vegetables are you supposed to consume in a day? The answer would be 5 to 13 servings but surprisingly, you eat only 3 servings a day or maybe less, an amount too far below the recommended amount. Including lots of vegetables in the diet can help prevent various diseases; among these are heart ailment, high blood pressure, some types of cancer and macular degeneration.Vegetables contain important nutrients such as vitamins and minerals, phytochemicals and anti-oxidants. Loaded with nutrients, vegetables are usually low in calories and are very beneficial to people who want to lose weight. More colorful vegetables are more nutritious thus try to pick those that are dark in color – green, yellow and orange.These foods are good sources of vitamins A, C and E. Vitamin A promotes eye and skin health. Vitamin C makes your immune system stronger. They are rich in potassium which is necessary in controlling high blood pressure. Folic acid is essential in forming red blood cells. These low-calorie foods do not contain cholesterol thus lowering your risk of heart ailment. Full of anti-oxidants and dietary fiber, you lower your risk of colon cancer.Here is a guide to the most nutritious kinds of vegetables. There are three essential tips in choosing the kinds to include in your diet. Pick the green colored vegetables, especially the leafy ones. You should also choose summer veggies and less starchy kinds. These are all healthy but are low in calories.The suggested green leafy vegetables that are low in calories are lettuce, spinach and cabbage. Other low-calorie greens are celery and cucumber. A cup of shredded cabbage contains 32 calories; the same amount of spinach has 40 calories. A cup of celery has only 20 calories, sometimes zero or negative calories. This is because it takes too much energy to digest the celery which may even consume some of your stored energy. This is the reason why celery is very good for people on weight loss regimen.Try to stick to the summertime vegetables which are dark in color. You can have summer squash and zucchini. Other summertime veggies that are low in calories are tomatoes, radishes and mushrooms. A cup of cooked mushrooms has 40 calories; half cup of radishes contains only 10 calories while a medium-sized tomato has 25 calories.If you are counting your calories, you should refrain from eating too starchy foods. Most of these are loaded with calories. A cup of starchy vegetables normally contains 150 calories. Two kinds of squash belong to this category. These are the butternut and acorn varieties of squash. Other starchy vegetables are potatoes, parsnips, peas and corn. The non-starch kinds are broccoli, lettuce, turnips, cauliflower, celery and green bell peppers.As you eat these low-calorie dark green-colored leaves, summertime and non-starchy veggies, you should be careful in preparing them. Adding too much dressing can defeat the purpose. Many low-calorie vegetables have low-calorie content but end up with high count when served.