Table 15.1 National Institutes of Health Definitions of Overweight and Obesity
Figure 15.1 ▶ Prevalence of obesity in the United States, 2011-2014. (Source: Ogden, C., Carroll, M., Fryar, C., and Fiegal, K. . Prevalence of obesity among adults and youth: United States, 2011-2014. NCHS Data Brief No. 219. Available at www.cdc.gov/nchs/data/databriefs/db219.pdf. Accessed on 1/17/17.)
Figure 15.2 ▶ Trends in adult overweight, obesity, and extreme obesity among men and women aged 20 to 74 years. (Source: Fryar, Carroll, & Ogden, 2014.)
Adipose LPL activity increases after weight loss to promote fat deposition—the body’s attempt to maintain weight or composition through its own internal controls despite variations in calorie intake and energy expenditure. This phenomenon is known as the set-point theory.
(e.g., when the body is gaining weight). Ghrelin levels are usually high before eating and when there is a negative energy balance or low-calorie intake, which may explain why maintaining weight loss is so difficult. Researchers have found that eventually—perhaps a year after weight loss—ghrelin levels adjust to a new lower weight and revert toward before-weight loss levels (Iepsen, Lundgren, Holst, Madsbad, & Torekov, 2016), which may then help maintain weight loss.
An abundance of readily accessible, low-cost, palatable, high-calorie foods in large portions
Increasing consumption of snacks
A high intake of added sugars, including soft drinks
A great proportion of the food budget spent on food away from home
The increasing portion size of restaurant meals
A decrease in energy expenditure related to labor-saving devices, such as remote control devices and motorized walkways
An increase in sedentary leisure activities, such as watching television, playing video games, and sitting in front of a computer. Television watching may promote obesity by leaving less time for physical activity, lowering resting metabolic rate, and/or promoting greater meal frequency and food intake (Chaput, Klingenberg, Astrup, & Sjodin, 2011).
Weight loss is indicated for anyone with a BMI ≥30 (obese) or with a BMI of 25 to 29.9 (overweight) who have one risk for cardiovascular disease, such as diabetes, prediabetes, hypertension, dyslipidemia, high waist circumference, or other obesity-related comorbidities. Patients who are not ready or able to lose weight should be advised to avoid additional weight gain and are treated for cardiovascular and obesity-related conditions.
People who are overweight but without any risk factors or who are of normal weight with a history of overweight or obesity should be advised to frequently monitor their weight and adjust their calorie intake if they start to gain weight. They should also be encouraged to engage in regular physical activity to help avoid weight gain.
People who are at normal weight (BMI 18.5-24.9) should be advised to not gain weight.
If the patient intends to make changes to improve intake, physical activity level, and behavior, such as keeping a food diary, monitoring weight, and limiting sedentary time.
If the patient has made any changes to eat healthier, be more physically active, or improve specific behaviors in the last month.
How long the patient has been eating healthier, engaging in greater physical activity, and using behavior strategies.
and reduced need for medications to control blood glucose, triglycerides, and cholesterol. A 5% to 10% weight loss within 6 months is recommended.
Comprehensive lifestyle treatment, which serves as the foundation of weight management for all people. It includes nutrition therapy, physical activity, and behavioral strategies to facilitate adherence to a low-calorie diet and increased physical activity. Comprehensive lifestyle treatment alone will cause a substantial proportion of patients to lose enough weight to improve health (Jensen et al., 2014).
Medication may be considered as adjunct therapy for those who are not able to lose weight or maintain weight loss and have a BMI ≥30 or BMI ≥27 with comorbidity.
Bariatric surgery may be considered as an adjunct therapy when BMI ≥40 or BMI ≥35 with comorbidity.
Choose a general target to create a calorie deficit, such as 1200 to 1500 cal/day for women and 1500 to 1800 cal/day for men. These levels are adjusted according to the individual’s body weight and physical activity levels.
Prescribe a calorie level that is 500 to 750 cal/day less than estimated need. Estimated need can be determined by indirect calorimeter if available. If it is not, the Mifflin-St. Jeor equation using actual body weight is used to estimate resting metabolic rate, which is then multiplied by an activity factor to estimate total calorie needs per day (Box 15.1). A hypocaloric plan is achieved by either subtracting 500 to 750 cal or 30% from the total estimated needs.
An ad lib approach that does not necessarily prescribe a specific calorie level but achieves a calorie deficit by restricting or eliminating particular food groups, such as a low-carbohydrate or low-fat eating plan
Use Mifflin-St. Jeor equation to estimate resting metabolic rate.
Men: RMR = (10W) + (6.25H) – (4.92A) + 5
Women: RMR = (10W) + (6.25H) – (4.92A) – 161
Multiply RMR by a physical activity factor to estimate total calorie needs.
Sedentary: 1.0 or more to < 1.4
Low active: 1.4 to < 1.6
Active: 1.6 to < 1.9
Very active: 1.9 to < 2.5
Table 15.2 Evidence-Based Dietary Approaches Associated with Weight Loss if Low-Calorie Intake Is Achieved
resulting from high-protein diets (25% of calories) is the same as that from a typical protein diet (15% of calories) when the diets provide the same number of total calories (Jensen et al., 2014). High-protein weight loss diets do not result in better cardiometabolic outcomes than normal protein weight loss diets.
Table 15.3 A Comparison of Weight Loss Diet Plans and Sample Menus