Using the food pyramid, Food groups
The food pyramid was developed by the U.S. Department of Agriculture (USDA) as a nutrition guide for healthy persons over the age of two years. The guide stresses eating a wide variety of foods from the five major food groups while minimizing the intake of fats and sugars. The daily quantity of foods from each group is represented by the triangular shape. The pyramid is composed of four levels. The tip represents fats and sweets, the second level emphasizes foods primarily from animals (milk and meat groups), the third level emphasizes foods from plants (vegetable and fruit groups), and the bottom level emphasizes foods from grains (breads, cereals, and rice).
The food guide pyramid was developed in 1992 as a modification of the previously used Basic Four food guide. The updated guide was designed to provide nutritional information in a manner that was easily understood by the public. Also, the pyramid emphasizes fats because the American diet is too high in fats. The guide was developed following the Recommended Dietary Allowances (RDA) and recommendations by certain health organizations.
The food pyramid guidelines for healthy living are:
- Balancing diet with physical activity
- Eating a variety of foods
- Eating plenty of vegetables, fruits, and grain products
- Eating foods low in fat, saturated fat, and cholesterol
- Eating sweets in moderation
- Eating salt in moderation
- Limiting intake of alcohol.
The recommended servings of each food group are expressed in ranges so that the pyramid can fit most members of a household. The number of servings chosen from each food group is based upon the number of calories a person needs. A calorie is the amount of energy obtained from food. Most persons should always have at least the lowest number of servings for each group. In general, the low to middle numbers of servings are appropriate for most women and the middle to upper numbers of servings are appropriate for most men. Servings do not need to be measured for grain products, vegetables, and fruits but should be followed carefully when eating foods that contribute a significant amount of fat (meats, dairy, and fats used in food preparation). Persons who are dieting should reduce their fat intake and increase physical activity but not reduce the number of servings from each group.
Sample daily diets at three calorie levels:
- Lower calorie diet. Nonactive women and some elderly persons may need a lower calorie diet (1,600 calories) comprised of: grains, six servings; vegetables, three servings; fruits, two servings; milks, two to three servings; meat, 5 oz (142 g); fat, 2 oz (53 g); and sugar, 6 teaspoons.
- Moderate calorie diet. Children, teenage girls, active women, pregnant or breast feeding women, and nonactive men may need a moderate calorie diet (2,200 calories) comprised of: grains, nine servings; vegetables, four servings; fruits, three servings; milks, two to three servings; meat, 6 oz (171 g); fat, 2.5 oz (73 g)s; and sugar, 12 teaspoons.
- Higher calorie diet. Teenage boys, active men, and active women may need a high calorie diet (2,800 calories) comprised of: grains, 11 servings; vegetables, five servings; fruits, four servings; milks, two to three servings; meat, 7 oz (198 g); fat, 3 oz (93 g); and sugar, 18 teaspoons.
Children between two and six years of age can follow the food pyramid but with smaller serving sizes (about two thirds of a regular serving) and two cups of milk daily. Preschool children may need fewer than 1,600 calories and children under the age of two years have special dietary needs. A pediatrician should be consulted as to the appropriate diet for young children. Persons with special dietary needs (vegetarians, diabetics, etc.) can consult a dietician or nutritionist.
Fats, oils, and sweets
Fats, oils, and sweets are at the very top of the pyramid because these foods should be used sparingly. In general, these foods provide only calories, little else nutritionally. Persons should choose lower fat foods from each group, reduce the use of fats (such as butter) and sugars (such as jelly) at the table, and reduce the intake of sweet foods (soda, candy, etc.).
Fats should not contribute more than 30% of a persons daily calories. To determine the number of grams of fat that contributes 30% of the calories multiply the total day's calories by 0.30 and divide by 9. For example, a 2,200 calorie diet should contain no more than 2.5 oz (73 g) of fat. Some fats are worse than others. The intake of saturated fats should be limited because they raise blood cholesterol levels which increases the risk of heart disease. Saturated fats are primarily found in animal and dairy products, and coconut, palm, and palm kernel oils. Saturated fats should not contribute more than 10% of the daily calories. Unsaturated fats are a healthier choice and include olive, peanut, canola, safflower, corn, sunflower, cottonseed, and soybean oils. Cholesterol is a fat-like molecule found only in animal products. Egg yolks and liver are especially high in cholesterol. Daily cholesterol intake should be limited to 300 mg or less.
The daily intake of sugar should be limited to 6 tsp for a diet of 1,600 calories. Sugars include white sugar, raw sugar, brown sugar, corn syrup, molasses, and honey. Naturally found sugars, those in fruits, 100% fruit juices, and milk, are not a major source of sugar in the American diet.
Fats, oils, and sweets are often found in foods from the five groups. For instance, meats contain fats and baked goods contain fats and sugars. These sources should be considered when choosing foods from each group. To reduce the intake of fats, leaner cuts of meat, low fat milk, unsaturated vegetable oils, and margarines prepared from liquid vegetable oil should be chosen.
Milk, yogurt, and cheese
The food pyramid recommends two to three servings of milk products daily. Women who are pregnant or breast feeding, teenagers, and adults up to the age of 24 years need three servings daily. Milk products are the best food source of calcium and also provide protein, minerals, and vitamins. A serving size is one cup of milk or yogurt, 2 oz (56 g) of processed cheese, or 1.5 oz (43 g) of natural cheese. To reduce the intake of fat and cholesterol, skim milk, nonfat yogurt, and low fat cheese and milk desserts should be chosen. The intake of high fat ice cream and cheeses should be reduced.
Meat, poultry, fish, dry beans, eggs, and nuts
The food pyramid recommends eating two to three servings (or 5-7 oz [142-198 g] of meat) from this group. Meat, fish, and poultry provide protein, iron, zinc, and B vitamins. Eggs, nuts, and dry beans supply protein, vitamins, and minerals. To help determine the serving size of meats, an average hamburger is about 3 oz. One half a cup of cooked dry beans, 2 tbsp of peanut butter, one egg, or one third a cup of nuts are all equivalent to 1 oz (28 g) of meat.
Lean meats and poultry should be chosen to reduce the intake of fat and cholesterol. Lean meats include: sir-loin steak, pork tenderloin, veal (except ground), lamb leg, chicken and turkey (without skin), and most fish. The intake of nuts and seeds, which contain large amounts of fat, should be reduced.
The food guide pyramid recommends eating three to five servings of vegetables each day. Vegetables provide vitamins, minerals, and fiber, and are low in fat. A serving size of vegetable is 1 cup of raw salad greens, one half a cup of other cooked or raw vegetables, or three quarters of a cup of vegetable juice. Limit the use of toppings or spreads (butter, salad dressing, mayonnaise, etc.) because they add fat calories.
The food pyramid recommends eating a variety of vegetables because different classes of vegetables provide different nutrients. Vegetables classes include: dark green leafy (broccoli, spinach, romaine lettuce, etc.), deep yellow (sweet potatoes, carrots, etc.), starchy (corn, potatoes, peas, etc.), legumes (kidney beans, chickpeas, etc.), and others (tomatoes, lettuce, onions, green beans, etc.). The vegetable subgroups dark green leafy and legume should be chosen often because they contain more nutrients than other vegetables. Also, legumes can substitute for meat.
The food guide pyramid recommends two to four servings of fruit daily. Fruits provide vitamin A, vitamin C, and potassium and are low in fat. A serving size of fruit is three quarters of a cup of fruit juice, one half a cup of cooked, chopped, or canned fruit, or one medium sized banana, orange, or apple.
The food pyramid recommends choosing fresh fruits, 100% fruit juices, and canned, frozen, or dried fruits. Intake of fruits that are frozen or canned in heavy syrup should be limited. Whole fruits are preferred because of their high fiber content. Melon, citrus, and berries contain high levels of vitamin C and should be chosen frequently. Juices that are called punch, -ade, or drink often contain considerable added sugar and only a small amount of fruit juice.
Bread, cereal, rice, and pasta
With 6-11 servings daily, this food group is the largest group, hence the bottom position on the pyramid. This group provides complex carbohydrates (starches), which are long chains of sugars, as well as vitamins, minerals, and fiber. Carbohydrates are the gasoline for the body's many energy-requiring systems. A serving size from this group is one slice of bread, 1 oz (27 g) of cold cereal, or one half a cup of pasta, rice, or cooked cereal.
Complex carbohydrates in and of themselves are not fattening, it is the spreads and sauces used with these foods that add the most calories. For the most nutrition, foods prepared from whole grains (whole wheat bread or whole grain cereals for instance) with little added fat and/or sugar should be chosen. The intake of high fat and/or high sugar baked goods (cakes, cookies, croissants, etc.) and the use of spreads (butter, jelly, etc.) should be reduced.
Francis, Frederick. Wiley Encyclopedia of Food Science and Technology. New York: Wiley, 1999.
The Food Guide Pyramid. United States Department of Agriculture Center for Nutrition Policy and Promotion, Home and Garden Bulletin, Number 252.
Shaw, Anne, Lois Fulton, Carole Davis, and Myrtle Hogbin. Using The Food Guide Pyramid: A Resource For Nutrition Educators. U.S. Department of Agriculture Food, Nutrition, and Consumer Services, Center for Nutrition Policy and Promotion.
Tips For Using The Food Guide Pyramid For Young Children 2 to 6 Years Old. United States Department of Agriculture Center for Nutrition Policy and Promotion, Program Aid 1647. 1999.
USDA Food Guide Pyramid [cited February 2003]. <http. www.nal.usda.gov.8001/py/pmap.htm>.
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