Dietary Guidelines for Americans - SchoolNutritionAndFitness.com

Chapter 2Balancing Caloriesto Manage WeightAchieving and sustaining appropriate body weightacross the lifespan is vital to maintaining good healthand quality of life. Many behavioral, environmental,and genetic factors have been shown to affect a person’sbody weight. Calorie balance over time is the keyto weight management. Calorie balance refers to therelationship between calories consumed from foodsand beverages and calories expended in normal bodyfunctions (i.e., metabolic processes) and throughphysical activity. People cannot control the caloriesexpended in metabolic processes, but they cancontrol what they eat and drink, as well as how manycalories they use in physical activity.Calories consumed must equal calories expendedfor a person to maintain the same body weight.Consuming more calories than expended will resultin weight gain. Conversely, consuming fewer caloriesthan expended will result in weight loss. This can beachieved over time by eating fewer calories, beingmore physically active, or, best of all, a combinationof the two.Maintaining a healthy body weight and preventingexcess weight gain throughout the lifespan are highlypreferable to losing weight after weight gain. Once aperson becomes obese, reducing body weight backto a healthy range requires significant effort overa span of time, even years. People who are mostsuccessful at losing weight and keeping it off do sothrough continued attention to calorie balance.The current high rates of overweight and obesityamong virtually all subgroups of the population inthe United States demonstrate that many Americansare in calorie imbalance—that is, they consume morecalories than they expend. To curb the obesity epidemicand improve their health, Americans need tomake significant effortsto decrease the totalnumber of calories theyconsume from foodsand beverages andincrease calorie expenditurethrough physicalfor More inforMationSee chapter 5 for discussionof healthy eatingpatterns that meet nutrientneeds within calorie limits.DIETARY GUIDELINES FOR AMERICANS, 2010 | Chapter Two 8