Contents | Previous | Next |
Reported dietary intakes of the following nutrients are low enough to be of concern:
Efforts are warranted to promote increased dietary intakes of vitamin E, potassium, and fiber regardless of age; increased intakes of vitamins A and C, calcium, and magnesium by adults; and increased intakes of calcium and magnesium by children age 9 years or older. Efforts are especially warranted to improve the dietary intakes of adolescent females.
Two major aspects of the USDA dietary pattern contribute to meeting nutrient intake recommendations:
A sedentary lifestyle limits the amount of calories needed to maintain one's weight. Careful food selection is needed to meet recommended nutrient intakes within this calorie limit. Diets that include foods with a high nutrient content relative to calories are helpful in achieving recommended nutrient intakes without excess calories. Diets that include a large proportion of foods or beverages that are high in calories but low in nutrients are unlikely to meet recommended intakes for micronutrients and fiber, especially for sedentary individuals.
By careful planning that considers the relative nutrient content of different foods, substitutions can be made to a food intake pattern to achieve recommended nutrient intakes.
Special nutrient recommendations are warranted for the following subgroups and nutrients:
A conclusion specific to each group and nutrient can be found in Part D, Section 1, Question 5.
Regular physical activity is essential to the maintenance of a healthy weight and reduces risk for the development of a number of chronic diseases. At least 30 minutes of moderate physical activity on most days provides important health benefits in adults. More than 30 minutes of moderate to vigorous physical activity on most days provides added health benefits. Many adults may need up to 60 minutes of moderate to vigorous physical activity on most days to prevent unhealthy weight gain.
Vigorous physical activity (e.g., jogging or other aerobic exercise) provides greater benefits for physical fitness than does moderate physical activity and burns calories more rapidly per unit of time.
Exercise that loads the skeleton has potential to reduce the risk of osteoporosis by increasing peak bone mass during growth, maintaining peak bone mass during adulthood, and reducing the rate of bone loss during aging.
Resistance exercise training increases muscular strength and endurance and maintains or increases lean body weight. These benefits are seen in adolescents, adults, and older adults who perform 8 to 10 resistance exercises 2 or more days per week.
Children and adolescents need at least 60 minutes of moderate to vigorous physical activity on most days for maintenance of good health and fitness and for healthy weight during growth. Reducing sedentary behaviors, including television- and video-viewing time, appears to be an effective way to treat and prevent overweight among children and adolescents.
Although the contribution of physical activity to weight loss usually is modest, acquiring a routine of regular physical activity will help an adult to maintain a stable body weight after successful weight loss. The amount of physical activity that weight-reduced adults need to avoid weight regain is estimated to be from 60 to 90 minutes daily at moderate intensity.
Weight maintenance depends on a balance of energy intake and energy expenditure, regardless of the proportions of fat, carbohydrate, and protein in the diet. Weight loss occurs when energy intake is less than energy expenditure, also regardless of the proportions of fat, carbohydrate, and protein in the diet. For adults, well-planned weight-loss diets that are consistent with the Accepted Macronutrient Distribution Ranges (IOM, 2002) for fat, carbohydrate, and protein can be safe and efficacious over the long term. The recommended ranges for fat calories (20 to 35 percent of total calories), carbohydrate calories (45 to 65 percent of total calories), and protein calories (10 to 35 percent of total calories) provide sufficient flexibility to accommodate weight maintenance for a wide variety of body sizes and food preferences.
Available data are insufficient to determine the contribution of energy dense foods to unhealthy weight gain and obesity. However, consuming energy dense meals may contribute to excessive caloric intake. Conversely, eating foods of low energy density may be a helpful strategy to reduce energy intake when trying to maintain or lose weight.
The amount of food offered to a person influences how much he or she eats; and, in general, more calories are consumed when a large portion is served rather than a small one. Thus, steps are warranted for consumers to limit the portion size they take or serve to others, especially for foods that are energy dense.
At low intakes of fat (< 20 percent of energy) and high intakes of carbohydrates (>65 percent of energy), risk increases for inadequate intakes of vitamin E, α linolenic acid, and linoleic acid and for adverse changes in high-density lipoprotein (HDL) cholesterol and triglycerides. At high intakes of fat (> 35 percent of energy), the risk increases for obesity and coronary heart disease (CHD). This is because fat intakes that exceed 35 percent of energy are associated with both increased calorie and saturated fat intakes. Total fat intake of 20 to 35 percent of calories is recommended for adults and 25 to 35 percent for children age 4 to 18 years. A fat intake of 30 to 35 percent of calories is recommended for children age 2 to 3 years.
The relationship between saturated fat intake and low-density lipoprotein (LDL) cholesterol is direct and progressive, increasing the risk of cardiovascular disease (CVD). Thus, saturated fat consumption by adults should be as low as possible while consuming a diet that provides 20 to 35 percent calories from fat and meets recommendations for α linolenic acid and linoleic acid. In particular,
The relationship between trans fatty acid intake and LDL cholesterol is direct and progressive, increasing the risk of CHD. Trans fatty acid consumption by all population groups should be kept as low as possible, which is about 1 percent of energy intake or less.
The relationship between cholesterol intake and LDL cholesterol concentrations is direct and progressive, increasing the risk of CHD. Thus, cholesterol intake should be kept as low as possible within a nutritionally adequate diet. In particular,
An n-6 PUFA intake between 5 to 10 percent of energy may confer beneficial effects on coronary artery disease mortality.
An α-linolenic acid intake between 0.6 to 1.2 percent of calories will meet requirements for this fatty acid and may afford some protection against CVD outcomes.
The consumption of two servings per week of fish high in eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) is associated with reduced risk of both sudden death and CHD death in adults. To benefit from the potential cardioprotective effects of EPA and DHA, the weekly consumption of two servings (approximately 8 ounces) of fish, particularly fish rich in EPA and DHA is suggested. Other sources of EPA and DHA may provide similar benefits; however, further research is warranted.
There is an inverse relationship between the intake of monounsaturated fatty acids (MUFAs) and the total cholesterol (TC):HDL cholesterol concentration ratio. If equal amounts of MUFAs are substituted for saturated fatty acids, LDL cholesterol decreases.
The intake of carbohydrates (including sucrose, glucose, fructose, lactose, and starch) contributes to dental caries by providing substrate for bacterial fermentation in the mouth. Drinking fluoridated water and/or using fluoride-containing dental hygiene products help reduce the risk of dental caries. A combined approach of reducing the frequency and duration of exposure to fermentable carbohydrates and optimizing oral hygiene practices is the most effective way to reduce caries incidence.
A potential health concern for foods that raise blood glucose levels and initiate an insulin response is that they may eventually lead to diabetes. Current evidence suggests that there is no relationship between total carbohydrate intake (minus fiber) and the incidence of either type 1 or type 2 diabetes. The intake of fiber-containing foods is associated with a decreased risk of type 2 diabetes in a number of epidemiological studies.
Current evidence suggests that glycemic index and/or glycemic load are of little utility for providing dietary guidance for Americans.
Compared with individuals who consume small amounts of foods and beverages that are high in added sugars, those who consume large amounts tend to consume more calories but smaller amounts of micronutrients. Although more research is needed, available prospective studies suggest a positive association between the consumption of sugar-sweetened beverages and weight gain. A reduced intake of added sugars (especially sugar-sweetened beverages) may be helpful in achieving recommended intakes of nutrients and in weight control.
Diets rich in dietary fiber have a number of important health benefits including helping to promote healthy laxation, reducing the risk of type 2 diabetes, and decreasing the risk of CHD. Prospective cohort studies suggest that decreased risk of heart disease is associated with the intake of 14 g of dietary fiber per 1,000 calories.
Greater consumption of fruits and vegetables (5 to 13 servings or 2 ˝ to 6 ˝ cups per day depending on calorie needs3) is associated with a reduced risk of stroke and perhaps other CVDs, with a reduced risk of cancers in certain sites (oral cavity and pharynx, larynx, lung, esophagus, stomach, and colon-rectum), and with a reduced risk of type 2 diabetes (vegetables more than fruit). Moreover, increased consumption of fruits and vegetables may be a useful component of programs designed to achieve and sustain weight loss.
Consuming at least 3 servings (approximately equivalent to 3 ounces) of whole grains per day can reduce the risk of diabetes and CHD and help with weight maintenance. Thus, daily intake of three or more servings of whole grains per day is recommended, preferably by substituting whole grains for refined grains.
Consuming three servings (equivalent to 3 cups) per day of milk and milk products each day can reduce the risk of low bone mass and contribute important amounts of many nutrients. Furthermore, this amount of milk product consumption may have additional health benefits and is not associated with increased body weight. Therefore, the intake of three servings of milk products per day is recommended.
The combination of thirst and usual drinking behavior, especially the consumption of fluids with meals, is sufficient to maintain normal hydration. Healthy individuals who have routine access to fluids and who are not exposed to heat stress consume adequate water to meet their needs. Purposeful drinking is warranted for individuals who are exposed to heat stress or who perform sustained vigorous activity.
The relationship between salt (sodium chloride) intake and blood pressure is direct and progressive without an apparent threshold. Hence, individuals should reduce their salt intake as much as possible. In view of the currently high levels of salt intake, a daily sodium intake of less than 2,300 mg is recommended. Many persons will benefit from further reductions in salt intake, including hypertensive individuals, blacks, and middle- and older-aged adults. Individuals should concurrently increase their consumption of potassium because a diet rich in potassium blunts the effects of salt on blood pressure.
Diets rich in potassium can lower blood pressure and lessen the adverse effects of salt on blood pressure, may reduce the risk of developing kidney stones, and possibly decrease bone loss. In view of the health benefits of potassium and its relatively low intake by the general population, a daily potassium intake of at least 4,700 mg is recommended. Blacks are especially likely to benefit from an increased intake of potassium.
A daily intake of one to two alcoholic beverages is not associated with inadequate intake of macronutrient or micronutrients, or with overall dietary quality.
The behaviors in the home that are most likely to prevent a problem with foodborne illnesses are
Avoiding higher-risk foods is an important protective measure (e.g., deli meats and frankfurters that have not been reheated to a safe temperature may contain Listeria). This is especially important for high-risk groups (the very young, pregnant women, elderly and those who are immunocompromised).
1Some patterns designed to meet nutrient intake recommendations divide this group into two groups: (1) meat, poultry, and fish and (2) seeds, dry peas and beans, and nuts.
2For persons with known heart disease, medical advice and the use of ATP III Panel Guidelines are indicated.
3See Tables D1-13 and D1-16 for information on 2 to 3 year olds.