Children, teens and adults need a balanced diet that includes foods from five groups: fruits, vegetables, grains, protein sources and dairy or other calcium-rich products, according to the U.S. Department of Agriculture. Getting enough of each food group daily can help ensure you don't become deficient in vital vitamins and minerals and may lower your risk of diseases like cancer, heart disease, hypertension and diabetes. A simple way to check that your diet is measuring up is to follow the USDA's MyPlate guidelines for planning your meals, notes Kathleen Zelman, M.P.H., R.D., L.D. in a UnitedHealthcare article 4. If you're having trouble designing a healthy diet, talk to your doctor or a nutritionist.

Have half of each meal consist of fresh, frozen or canned fruits or vegetables. Choose low- or no-sodium brands of vegetables and fruit packed in 100 percent fruit juice if you use canned produce. Aim to eat as many different colors of produce each week as possible, such as red cherries, yellow-orange winter squash, green spinach, blueberries and purple eggplant.

Make 25 percent of each meal a grain such as rice, pasta or bread. Consume at least half of these grains in their whole-grain form such as brown rice, whole-wheat bread, whole-grain noodles or whole cereal grains like oatmeal or bulgur instead of white rice and other products prepared from refined grains.

Include a protein-rich food at every meal. Choose from poultry, lean meats, fish, shellfish, eggs, nuts, seeds, soy foods, beans or legumes. Keep in mind that a single serving consists of one egg, 1/2 ounce of nuts or seeds, 1/4 cup of cooked beans or 1 ounce of seafood, meat or poultry.

Consume a serving of dairy or an appropriate high-calcium vegetarian option with each meal. Try 1 1/2 ounces of low-fat cheese or 1 cup of low- or nonfat yogurt or milk if you include dairy products in your diet. Opt for 1 cup of calcium-fortified plant milk, fortified soy foods or dark green leafy vegetables as alternatives or if you don't consume dairy.