Power up your plate: add nutritional punch to your meals with these 13 "super foods".

How healthy is your diet? If you're like most people, you probably tend to eat the same meals day after day--cereal and fruit for breakfast, a sandwich for lunch, pasta for dinner, and maybe something sweet for dessert.

Not that there's anything wrong with that. Many foods can be a part of a healthy eating plan. But the fact is that some foods pack far more nutritional punch per serving. Add more of these "super foods" to your regular eating plan, and you'll boost your vitamin and mineral intake.

Incorporating these nutrient-dense foods into your diet is particularly important if you're trying to lose weight, says Joan Carter of Houston, Texas, a registered dietitian and spokesperson for the American Dietetic Association. "It's the nutritional bang for your calorie," says Carter. "If you're watching your weight and consume only 1,600 calories per day, for example, you want to be sure that those calories are spent wisely."

Do you think because you work out that you don't have to worry about food choices? Think again, Carter says. "People who are really active can have a little more swing in terms of the number of calories they can consume, but they're also putting more demands on their bodies," she says. "Most casual athletes don't have huge increases over the standard United States recommended daily allowances, but for anyone, choosing food that gives you good nutrition will basically make you feel better. A good diet can be your best friend in terms of your athletic performance."

So, the next time you're dining out or shopping for groceries, give these 13 super foods a try:

Spinach

Do your salads consist mostly of iceberg or leaf lettuce, Add spinach to your salad, and you'll get much more from your bowlful of greens. "Spinach is at the top of my list," Carter says. "You'll get much more bang for your caloric because you get vitamin A, iron, and folic acid." In general, the darker the greens, the more nutrients they contain

Collard Greens 

You probably didn't know that a cup of collard greens has as much calcium as a cup of milk. "Collard greens are an excellent source of calcium and are low in calories if you cook them right," Carter says.

Strawberries

Strawberries aren't just delicious; they're loaded with folic acid and are high in vitamin C. A cup of strawberries contains only 45 calories, yet almost four grams of fiber, too. Add some to your cereal in the morning, eat them with your lunch, or serve them with low-fat or nonfat yogurt for a light dessert.

Asparagus

If you turned up your nose at asparagus as a kid (or an adult), you may want to reconsider. Asparagus is high in folic acid, which helps prevent spina bifida and other neural tube birth defects, and new research suggests folic-acid rich foods such as asparagus play a role in preventing heart disease. It's also a natural diuretic--if you tend to bloat before your period, add some asparagus to your meals the week before to help relieve water weight gain.

Oats

You've probably heard that oatmeal is a healthy way to start your day, and for good reason. "Oats are high in soluble fiber, which is what makes it gummy when you cook it," says Carter. "It mops up cholesterol and helps keep your blood cholesterol low." Look for cereals that contain oats, or make instant oatmeal, which makes a quick, satisfying breakfast meal.

Walnuts

Walnuts and other nuts are a good source of omega-3 fatty acids, which are also found in fatty fish such as salmon. "A handful of walnuts will give you protein, and they're high in mono-saturated fats," Carter says. Walnuts are also high in vitamin C, a powerful antioxidant. Since they are high in calories (an ounce contains about 180 calories), limit yourself to small servings. Or try nut butters such as almond butter or peanut butter. Just remember that these are high in calories too.

Skim milk

You probably already know of skim milk's reputation-you get 302 milligrams of calcium and 8.4 grams of protein in a cup of skim milk without any added fat. When you're cooking, however, you may want to experiment with evaporated skim milk. "It's got double the calcium of skim milk, and you can use it to make soups, casseroles, and anything that you would add milk to," Carter says. It contains about 160 calories per cup.

Yogurt

Yogurt contains live cultures that are considered "probiotics." "Probiotics essentially colonize your intestine with happy bacteria that are good for you, as opposed to bad bacteria," Carter says. "And the reduced-fat versions of yogurt are low in calories and high in calcium." Try yogurt with cereal or fresh fruit for breakfast, or use plain, fat-free yogurt on your baked potato instead of sour cream.

Broccoli

When choosing vegetables, consider Broccoli--it's a great addition to soups or casseroles. Broccoli is high in vitamins A and C, and it's naturally filling--a cup of chopped raw broccoli will provide you with almost two and a half grams of fiber for only 80 calories.

Kiwi

The modest kiwi beats out many other fruits when it comes to nutrient composition per serving, Carter says. It's high in vitamins A and C, and two kiwifruits have more potassium than a banana. Kiwi can be a little tart, but its great served sliced in fruit salad with strawberries, grapes, melons, and other milder-tasting fruits.

Grapes

Grapes, particularly dark grapes, have polyphenolic compounds, the phytonutrients that help your body repair and maintain its cells, Carter says. Grapes are also high in water, which will help your body stay hydrated, especially if you exercise a lot. A cup of grapes has about 58 calories, and they're a good source of potassium as well.

Beans

Beans are a good source of folic acid, and make a great substitute for meat-based protein. They're also high in fiber and relatively low in calories. For example, a cup of chickpeas (garbanzos) contains 269 calories and nearly 5.7 grams of fiber; a cup of black beans, 227 calories and 7.2 grams of fiber, and kidney beans, 225 calories and 6.4 grams of fiber. Include more beans in your meals. Try bean-based soups, make homemade chili, or eat more bean dishes when you dine at Mexican or Indian restaurants.

Tomatoes

Tomatoes are one of the most popular foods in the United States--we eat them in pizza, ketchup, pastas, salsa, and of course, fresh on salads and sandwiches. Tomatoes are high in vitamins A and C, and they contain lycopene, a phytochemical that appears to help prevent macular degeneration, a condition that can lead to blindness. And at only 36 calories for a medium-sized tomato, you're getting a lot of nutrition per serving.

As you plan your diet, don't just focus on calories. Think of vitamins, minerals, fiber, and phytochemicals you need as well. Make an effort to choose more nutrient-dense foods, and you should notice an improvement in your health and your performance both at and away from the gym.

Kelly James-Enger writes on health issues from Downers Grove, Illinois.

Eat Better, Easily

Looking for other ways to increase your nutrition? Try these easy methods:

* Add more whole grains to your diet. Instead of choosing white bread, opt for mixed-grain or multi-grain breads, and opt for brown rice over white.

* Hard-boil some eggs at the beginning of the week and slip one into your lunch for a quick, easy protein source--or slice them for a quick sandwich.

* Toss garbanzo beans (chickpeas) or kidney beans into your salads. You'll boost your fiber and nutrient intake and make it a more filling meal as well.

* Vary the types of fruits and vegetables you eat. At the grocery store, aim for a wide variety of colors in your cart--yellow, red, dark-green, purple, and orange.

* Try fruit smoothies to get more fruit servings into your day. Add protein powder, skim milk, and ice, and you'll have a quick and nutritious morning meal.