How to Maintain a Healthy Diet
Grain products, vegetables, and fruits are key parts of a varied diet. They are emphasized in this guideline because they provide vitamins, minerals, complex carbohydrates (starch and dietary fiber), and other substances that are important for good health. They are also generally low in fat, depending on how they are prepared and what is added to them at the table.
Fiber is found only in plant foods like whole-grained breads and cereals, beans and peas, and other vegetables and fruits. Because there are different types of fiber in foods, choose a variety of foods daily. Eating a variety of fiber-containing plant foods is important for bowel function, can reduce symptoms of chronic constipation, diverticular disease, and hemorrhoids, and may lower the risk for heart disease and some cancers.
However, some of the health benefits associated with a high-fiber diet may come from other components present in these foods, not just the fiber itself. For this reason, fiber is best obtained from foods rather than supplements.
Choose a Diet Low in Fat, Saturated Fat, and Cholesterol
Some dietary fat is needed for good health. Fats supply energy and essential fatty acids and promote absorption of the fat-soluble vitamins A, D, E, and K. More Americans are now eating less fat, saturated fat, and cholesterol-rich goods than in the recent past. Still, many people continue to eat high-fat diets. This guideline emphasizes the continued importance of choosing a diet with less total fat, saturated fat, and cholesterol.
Avoid High-Fat Foods
Some foods and food groups are higher in fat than others. Fats and oils, and some types of desserts and snack foods that contain fat provide calories but few nutrients. Many foods in the milk group and in the meat and beans group (which includes eggs and nuts, as well as meat, poultry, and fish) are also high in fat as are some processed foods in the grain group.
Fat, whether from plant or animal sources, contains more than twice the number of calories of an equal amount of carbohydrates or protein. Choose a diet that provides no more than 30 percent of total calories from fat. The upper limit on the grams of fat in your diet will depend on the calories you need. Cutting back on fat can help you consume fewer calories. For example, at 2,000 calories per day, the suggested upper limit of calories from fat is about 600 calories (65 grams of fat x 9 calories per gram = about 600 calories).
Saturated fat—Fats contain both saturated and unsaturated (monounsaturated and polyunsaturated) fatty acids. Saturated fat raises blood cholesterol more than other forms of fat. Reducing saturated fat to less than 10 percent of calories will help you lower your blood cholesterol level. The fats from meat, milk, and milk products are the main sources of saturated fats in most diets. Many bakery products are also sources of saturated fats. Vegetable oils supply smaller amounts of saturated fat.
Monounsaturated and polyunsaturated fat—Olive and canola oils are particularly high in monounsaturated fats; most other vegetable oils, nuts, and high-fat fish are good sources of polyunsaturated fats. Both kinds of unsaturated fats reduce blood cholesterol when they replace saturated fats in the diet. Remember that the total fat in the diet should be consumed at a moderate level—that is no more than 30 percent of calories. Mono- and polyunsaturated fat sources should replace saturated fats within this limit.
Partially hydrogenated vegetable oils, such as those used in many margarines and shortenings, contain a particular form of unsaturated fat known as trans-fatty acids that may raise blood cholesterol levels, although not as much as saturated fat.
Choose a Low Cholesterol Diet
The body makes the cholesterol it requires. In addition, cholesterol is obtained from food. Dietary cholesterol comes from animal sources such as egg yolks, meat (especially organ meats such as liver), poultry, fish, and higher fat milk products. Many of these foods are also high in saturated fats. Choosing foods with less cholesterol and saturated fat will help lower your blood pressure levels.
Avoid Too Much Sugar
Sugars are carbohydrates. Dietary carbohydrates also include the complex carbohydrates starch and fiber. During digestion all carbohydrates except fiber break down into sugars. Sugars and starches occur naturally in many foods that supply other nutrients. Examples of these foods include milk, fruits, some vegetables, breads, cereals, and grains. Some sugars are used as natural preservatives, thickeners, and baking aids in food. The body cannot tell the difference between naturally occurring and added sugars because they are identical chemically.
Because maintaining a nutritious diet and a healthy weight is very important, sugars should be used in moderation by most healthy people and sparingly by people with low calorie needs.
Avoid Too Much Sodium
Sodium and sodium chloride—known commonly as salt—occur naturally in foods, usually in small amounts. In the body, sodium plays an essential role in regulation of fluids and blood pressure. Most evidence suggests that many people at risk for high blood pressure reduce their chances of developing this condition by consuming less salt or sodium. Some questions remain, partly because other factors may interact with sodium to affect blood pressure.
Drink Alcohol in Moderation
Alcoholic beverages have been used to enhance the enjoyment of meals by many societies throughout human history. If adults choose to drink alcoholic beverages, they should do so only in moderation.
Current evidence suggests that moderate drinking is associated with a lower risk for coronary heart disease in some individuals. However, higher levels of alcohol intake raise the risk for high blood pressure, stroke, heart disease, certain cancers, accidents, violence, suicides, birth defects, and overall mortality (deaths).
Too much alcohol may cause cirrhosis of the liver, inflammation of the pancreas, and damage to the brain and heart. Heavy drinkers also are at risk of malnutrition because alcohol contains calories that may substitute for those in more nutritious foods.
What is moderation? Moderation is defined as no more than one drink per day for women and no more than two drinks per day for men.