1. Be physically active every day.
How much activity is needed to obtain health-related benefits?
Moderate amounts of activity are recommended for people of all ages. However, physical activity need not be strenuous to be beneficial. Sixty minutes of moderately intense activity, such as walking, can generate genuine health benefits, such as reducing body weight and lowering the risk of heart attack, hypertension, and death. Some kind of regular vigorous activity, however, is the best way to improve cardiovascular fitness.
Physical activity recommendations for adolescents:
Adolescents should strive for 60 minutes or more of moderate to vigorous activity each day. To help achieve this, they should participate in at least three sessions of vigorous physical activity lasting 20 minutes or more each week. These guidelines are recommended minimum levels of activity for health.
What are the benefits of an active lifestyle?
Physical activity has the following benefits:
- Helps develop cardiovascular fitness, muscular strength, and confidence in physical ability
- Helps in maintaining a healthy body weight and reducing body fat
- Reduces stress and brightens a person’s mood
- Lowers the risk of diabetes, high blood pressure, and colon cancer, which can lead to premature death
2. Limit your screen time to no more than two hours each day.
Why is television viewing a negative influence on health?
Research has shown that television viewing affects both the physical activity and diet of youth (and children and adults too!) in very negative ways. Television advertising leads to excess energy intake and consumption of food low in nutritional value (e.g., soda, fast food). Television and other screen time leads to many hours per day of inactivity, limiting time for moderate and vigorous physical activity.
How much time do adolescents spend watching TV?
According to Dietz (1991), American children spend more time watching TV than they do engaging in any other activity except sleeping. In 2005 the average adolescent viewed approximately 21 hours per week, but that number jumps to 28 hours when you include videos, DVDs, and prerecorded shows. This is nearly as much time as is spent in school. Add to this computers, video games, and other media that might be in use simultaneously and all together youth pack about eight and a half hours of media content into about six and a half hours of time every day. Essentially, for many children media consumption has become a full-time job!
What are the risks of a sedentary lifestyle?
Activity is required for health. Studies suggest that physically active people enjoy lower risks of developing cardiovascular disease, diabetes, colon cancer, osteoporosis, anxiety, and depression relative to sedentary people. Sedentary habits increase the risk of death from these diseases. TV viewing is one of the major causes of overweight (obesity) among youth. TV watching has also been associated with elevated cholesterol levels and poor cardiovascular fitness.
What are some examples of things you can do to increase your activity and decrease your inactivity?
Take the stairs; don’t park next to the building; walk around the mall or the neighborhood with friends; watch only your favorite TV shows; remove or unplug the TV in your bedroom; play catch with a sibling, friend, or parent.
3. Eat five or more fruits and vegetables (combined) per day.
What are the main benefits of fruits and vegetables?
- Many are good sources of potassium, fiber, and vitamins C, A, and B.
- They are low in fat.
- They reduce the risk of certain forms of cancer.
- They provide nutrients important for immunity, healing, and healthy skin and eyes, among other functions.
How many fruits and vegetables should we eat daily?
The five-a-day campaign recommends five or more servings (combined) of fruits and vegetables a day. For adolescents, eating a fruit or vegetable with every meal and snack is a good goal to aim for without getting overly concerned with counting servings.
A serving size for foods in the fruit or vegetable group equals a medium-size piece of fruit, a small glass of 100 percent fruit juice, 1 cup of raw salad greens, 1/2 cup of cut-up fruit or vegetables, 1/2 cup of cooked vegetables or beans, or 1/4 cup of dried fruit. Many foods are typically eaten in portion sizes larger than one serving, so getting the recommended amount is easier than you may think.
4. Eat more whole grains and less added sugar.
Sugar-sweetened beverages (soda, sport drinks, fruit drinks) are the single largest source of added sugar in youths’ diets. Because they offer so many calories and so little nutritional value, it is best not to drink more than two 8-ounce (250-milliliter) servings of sugar-sweetened beverages per week. Instead, choose water and low-fat (or fat-free) milk as primary beverage choices. Consume "sweets" only sometimes, and check food labels to avoid products with sugar in the first three ingredients.
Youth need between six and eight servings from the grains group every day, and at least three of those servings should come from whole grain sources to get the health benefits of fiber, plant oils, and other micronutrients that are not present in foods made with refined grains. A grains serving is equal to one slice of bread, 1 cup of breakfast cereal, or a 1/2 cup of cooked rice or pasta.
5. Eat foods low in saturated fat and containing no trans fat.
What are the recommendations for fat intake?
The type of fat you eat is more important to your health than the total fat in your diet. Unsaturated fat comes from plant and fish oils and includes both mono- and polyunsaturated forms. Unsaturated fat is liquid at room temperature (think of cooking oils). Research shows a strong association between these healthy oils and lower rates of heart disease and type 2 diabetes. Therefore, most of the fat you consume should be unsaturated. Sources include fish, vegetable cooking oils, nuts, seeds, and whole grains.
Saturated fat mostly comes from animal sources such as meat and dairy foods and is solid at room temperature (think of butter and lard). Eating too much saturated fat raises blood cholesterol and increases the risk for heart disease. Nutrition experts recommend limiting saturated fat to no more than 10 percent of calories in the diet to reduce the risk for heart disease. (Current American Heart Association guidelines are even lower.)
Trans fat is another type of unhealthy saturated fat. Most trans fat in the diet comes from vegetable oils that have been chemically modified through a process called hydrogenation to improve the shelf life of foods such as baked goods, snack foods, and fast foods (think fried sandwiches and French fries). A much smaller amount comes from naturally occurring trans fat in certain types of meats. Trans fat is more heart unhealthy than saturated fat because it raises unhealthy LDL cholesterol and lowers protective HDL cholesterol. Because there is no recommended safe level of trans fat in the diet (Willett, 2005), it is best to eliminate it (at least what’s commercially produced) completely.
Avoid trans fat by consuming only foods listing no partially hydrogenated vegetable oils in the ingredients, cooking with liquid vegetable oils instead of stick margarine or shortening, and choosing trans-fat -free foods when eating out (e.g., no French fries).
Should we try to eliminate fat from our diets?
No! Fat has many important functions in our bodies.
- Fat and oils (also called lipids) add flavor, aroma, and texture to food. Lipids provide a feeling of fullness because they take longer to digest than carbohydrate and protein and remain in the stomach for a longer time.
- Dietary fat is essential for the absorption of the fat-soluble vitamins A, D, E, and K.
- Fat is a major source of energy.
- Essential fatty acids are needed for normal tissue function throughout the body. Deficiency syndromes can develop if they are missing from the diet.
Because saturated fat is contained in many foods that provide useful nutrients (meats and dairy products), it’s not practical to eliminate these foods altogether. However, you can limit saturated fat to a healthy level by consuming low-fat or fat-free dairy foods and lean meats and by substituting vegetable oils for butter when cooking.
Read more from Planet Health: An Interdisciplinary Curriculum for Teaching Middle School Nutrition and Health by Jill Carter, Jean L. Wiecha, Karen E. Peterson, Suzanne Nobrega, and Steven L. Gortmaker.