The current dietary intake of Americans has contributed to the obesity epidemic. Many children and adults have a usual calorie intake that exceeds their daily needs, and they are not physically active enough to compensate for these intakes. The com-bination sets them on a track to gain weight. On the basis of national survey data, the average calorie intake among women and men older than age 19 years are estimated to be 1,785 and 2,640 calories per day, respectively. While these estimates do not appear to be excessive, the numbers are dificult to interpret because survey respondents, especially individuals who are overweight or obese, often underreport dietary intake. Well-controlled studies suggest that the actual number of calories consumed may be higher than these estimates.
Table 2-2 provides the top sources of calories among Americans ages 2 years and older. The table reveals some expected differences in intake between younger (ages 2 to 18 years) and adult (ages 19 years and older) Americans. For example, alcoholic beverages are a major calorie source for adults, while luid milk provides a greater contribution to calorie intake for children and adolescents. Further, while not shown in the table,there is additional variability in calorie sources among children, adolescents, and adults of different ages. For example, sugar-sweetened bever-ages and pizza are greater calorie contributors for those ages 9 to 18 years than for younger children. Also, dairy desserts35 and ready-to-eat cereals provide a greater contribution to calorie intake for those ages 1 years and older than they do among younger adults.
Although some of the top calorie sources by category are important sources of essential nutrients, others provide calories with few essential nutrients. Many of the foods and beverages most often consumed within these top categories are in forms high in solid fats and/or added sugars, thereby contributing excess calories to the diet. For example, many grain-based desserts are high in added sugars and solid fats, while many chicken dishes are both breaded and fried, which adds a substantial number of calories to the chicken.
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| Current Food and Beverage Dietary Intake |
Calorie Balance: food and Beverage intake
Controlling calorie intake from foods and beverages is fundamental to achieving and attaining calorie balance. Understanding calorie needs, knowing food sources of calories, and recognizing associations between foods and beverages and higher or lower body weight are all important concepts when build-ing an eating pattern that promotes calorie balance and weight management. Many Americans are unaware of how many calories they need each day or the calorie content of foods and beverages.
The total number of calories a person needs each day varies depending on a number of factors, includ-ing the person’s age, gender, height, weight, and level of physical activity. In addition, a desire to lose, maintain, or gain weight affects how many calories should be consumed. Table 2-3 provides estimated total calorie needs for weight maintenance based on age, gender, and physical activity level. A more detailed table is provided in Appendix 6. Estimates range from 1,600 to 2,400 calories per day for adult women and 2,000 to 3,000 calories per day for adult men, depending on age and physical activity level. Within each age and gender category, the low end of the range is for sedentary individuals; the high end of the range is for active individuals. Due to reductions in basal metabolic rate that occurs with aging, calorie needs generally decrease for adults as they age. Estimated needs for young children range from 1,000 to 2,000 calories per day, and the range for older children and adolescents varies substantially from 1,400 to 3,200 calories per day, with boys generally having higher calorie needs than girls. These are only estimates, and estimation of individual calorie needs can be aided with online tools.
Knowing one’s daily calorie needs may be a useful reference point for determining whether the calories that a person eats and drinks are appropriate in relation to the number of calories needed each day. The best way for people to assess whether they are eating the appropriate number of calories is to monitor body weight and adjust calorie intake and participation in physical activity based on changes in weight over time. A calorie deicit of 500 calories or more per day is a common initial goal for weight loss for adults. However, maintaining a smaller deicit can have a meaningful inluence on body weight over time. The effect of a calorie deicit on weight does not depend on how the deicit is produced—by reducing calorie intake, increasing expenditure, or both. Yet, in research studies, a greater proportion of the calorie deicit is often due to decreasing calorie intake with a relatively smaller fraction due to increased physical activity.
