Transcript Document
UNIT 7 SEMINAR NS 220 Module 7: Meeting Energy Needs Overview Overweight/obesity Energy Balance Dieting Fad Diets Weight Loss Success CDC Statistics- Obesity More than 1/3 of U.S. adults are obese. 16% of children and adolescents (ages 2-19 years) are obese. What chronic diseases and health issues should we be concerned about due to obesity? Adult Overweight and Obesity Overweight & obesity ranges are determined by using weight & height to calculate "body mass index" (BMI). BMI correlates with amount of body fat. BMI WHO Classifications: BMI <18.5= Underweight BMI 18.5-24.9= Normal BMI 25-29.9= Overweight BMI ≥ 30= Obese Obese Class I= 30-34.9; Class II= 35-39.9; Class III= ≥ 40 Energy Balance Equation Energy Input = Energy Output (or calories in = calories out) Energy Input= Calories from food Energy Output= Metabolism (BMR) Physical Activity Thermic Effect of Food Energy Output: Basal Metabolism (BMR): Physical Activity: Calories expended for vital organ functioning in resting state; ~60-70% of total calorie needs. Affected by gender, body composition/muscle tone, age, temperature, health status, thyroid hormone Calories burned influenced by weight, muscles used, length of time of exercise Thermic Effect of Food (TEF): Energy used to digest, absorb and process nutrients. Energy Balance Positive Energy Balance = Input > Output (eat more than expend) Results in weight gain Negative Energy Balance = Input < Output (eat less than expend) Results in weight loss Must have a calorie deficit of about 3500 kcal per week to lose one pound/week…deficit of 500 kcals/day over 7 days. Why “Diets” Don’t Work Obesity is a chronic disease Treatment requires long-term lifestyle changes (no quick fix). Dieters are misdirected More concerned about weight loss than healthy, active lifestyle. Unrealistic weight expectations. Fad Diets Emphasizes one or two foods. Severely restricts food choices; rigid eating plans. What nutrients are fad diets usually lacking? Temporary solution to weight loss…not longterm; focus is not on permanent eating, exercise, or behavior changes. What are your concerns about fad diets? Fad Diets- What to Watch Out For Promote quick weight loss Limited food selections; rituals Use of testimonials Cure-alls Recommend expensive supplements No permanent lifestyle changes advocated Critical of the scientific community Discussion What factors are affecting obesity? What can we do to help decrease obesity as well as prevent weight gain? Weight Loss Success National Weight Control Registry www.nwcr.ws Investigates characteristics of individuals who have succeeded at long-term weight loss. 45% lost weight on their own; 55% used a program. 98% modified their food intake. 94% increased their activity (walking most reported). Recommendations: Eating Calorie control Portions Eat less overall, but still choose variety of foods Stay within your daily calorie needs Plan meals ahead Write down what you eat; self-monitoring Focus on fruits, vegetables, whole grains, fat-free or low-fat milk and milk products, lean meats, poultry, fish, beans, eggs, and nuts Emphasize low in saturated fats, trans fats, cholesterol, salt, and added sugars Recommendations: Exercise Exercise on regular basis; ACSM Position To prevent weight gain: 150-250 min/week Weight loss: 150->250 min/week Weight maintenance after weight loss: >250 min/week Children and teens: 60 mins per day Donnelly JE, et al. Appropriate physical activity intervention strategies for weight loss and prevention of weight regain for adults. Medicine & Science in Sports & Exercise 2009; 41:459-471.