Nutrition: From Science to You - Chapter 15 Lecture PDF

Nutrition: From Science to You Fourth Edition Chapter 15 Weight Management Instructor:...

Nutrition: From Science to You Fourth Edition Chapter 15 Weight Management Instructor: April J. Stull, Ph.D, RDN, FAND Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Learning Outcomes 15.1 Explain why weight management is important to health and well-being. 15.2 Define the terms appetite, hunger, and satiety, and describe the physiological factors involved in regulating food intake. 15.3 Describe the role of hyperplasia and hypertrophy of adipocytes in the development of obesity. 15.4 Discuss the role of genetics and the environment in the development of underweight, overweight, and obesity. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Learning Outcomes 15.5 Describe the role of diet and exercise in achieving a reasonable rate of weight loss. 15.6 Design a food and exercise plan to maintain a healthy weight. 15.7 Describe the role of diet and exercise in achieving a healthy weight gain. 15.8 Describe the role of weight-loss drugs and surgery for reducing obesity. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved Prevalence of Overweight and Obesity (Year 2017-2018) Adults Aged ≥20 with obesity: 42.5% Aged ≥20 with overweight, including obesity: 73.6% Adolescents and Children Aged 12-19 years with obesity: 21.2% Aged 6-11 years with obesity: 20.3% Aged 2-5 years with obesity: 13.4% Textbook has outdated statistics Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved https://www.cdc.gov/nchs/fastats/obesity-overweight.htm  The Status of Obesity in America Americans spend over $60 billion annually on weight-loss solutions. The U.S. health care system spends $190 billion annually on obesity-associated medical conditions. https://money.usnews.com/money/personal-finance/articles/2013/01/02/the-heavy-price-of-losing- Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved weight#:~:text=According%20to%20data%20by%20Marketdata,programs%20to%20drinking%20diet%20soda. Why is Weight Management Important? Weight management is maintaining body weight within a healthy range (BMI of 18.5 to 24.9). Healthy weight is a body weight that does not increase risk for developing weight-related health problems or diseases. Healthy weight lowers risk for chronic disease. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  The AMA Considers Obesity a Disease In 2013, the American Medical Association (AMA) declared obesity a “disease.” Multi-metabolic and hormonal disease state Benefits to declaring it a disease – May change the way physicians approach obesity management (drug therapies and surgery) – May make it easier for individuals to get insurance coverage for treatment – More research funding may be allocated to addressing the obesity problem in the United States. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  The AMA Considers Obesity a Disease Downside to declaring it a disease – It may encourage more use of drugs and medical procedures to address the epidemic rather than encouraging lifestyle changes. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved Problems Associated With Being Obesity Hypertension Heat disease Decreased quality of Stroke life and longevity Elevated lipid levels Depression Low HDL cholesterol Reproductive problems Insulin resistance Gallbladder disease Certain cancers Joint stress Complications during osteoarthritis pregnancy Sleep apnea Complications with surgical procedures Metabolic syndrome Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Overweight and Social and Psychological Risks Overweight people are treated differently from people at a normal weight. – Suffer more discrimination – More likely to be denied job promotions and raises – People perceive them as lazy or weak-willed. Overweight and obese people are less likely to exercise Obese people have higher rates of suicide and are more likely to use drugs and alcohol. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Problems Associated With Being Underweight Anemia Heart irregularities Amenorrhea (loss of menstruation in women) At risk for low body protein and fat stores, and depressed immune system – Difficult to fight infections Lack vital nutrients Osteoporosis Infertility Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Underweight and Social and Psychological Risks Individuals who are underweight are more likely to be at greater risk for: – Irritability – Anger – Depression Compared to healthy adults – Underweight males have an increased risk of committing suicide – Underweight adults may be more socially withdrawn Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  How is Food Intake Regulated? Appetite is the desire to eat food whether or not there is physical hunger; psychological – Triggered by factors such as time of day, social occasions, emotions, or the sight or smell of food Hunger and satiety affect the desire to eat and to stop eating. – Hunger is the physical sensation associated with the need or intense desire for food; physiological – Satiety is the feeling of ''fullness'' produced by the consumption of food. – Hunger and satiety are controlled by hormones produced in the brain and the gastrointestinal tract. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved The Brain Controls Hunger and Satiation Two regions of the brain – Ventromedial nucleus – Lateral hypothalamus – Control eating behaviors in response to hormones released from the stomach, pancreas, small intestine, adipocytes, and the hypothalamus Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  How is Food Intake Regulated? Satiety is triggered by the ventromedial nucleus. – Cholecystokinin (CKK) and peptide YY (PYY) ▪ Secreted by the small intestine to stimulate satiety – Leptin ▪ Produced in adipose tissue ▪ Decreases hunger and food intake ▪ Regulates amount of fat stored ▪ Increases in amount when the fat stores increase Certain macronutrients, especially protein, promote satiety and reduce food intake. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Leptin The production of leptin is controlled by the obese gene (ob) Mice that have a defective form of the gene fail to produce leptin and can gain weight Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  How is Food Intake Regulated? Hunger is controlled by the lateral hypothalamus. – Ghrelin ▪ Secreted by the stomach ▪ Increased production tells the hypothalamus the body needs energy; stimulates hunger ▪ Increase in blood before a meal, between a meal, during sleep, and fasting ▪ Lean individuals have higher ghrelin levels. – Neuropeptide Y ▪ Produced in the hypothalamus and activated by ghrelin ▪ Stimulates hunger – Leptin (partly responsible) ▪ Drop in leptin when adipocytes shrinks, stimulates hunger Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  How Do Fat Cells Form and Expand? Growth of fat cells (adipocytes) occurs in two ways. – Can expand to store more fat (hypertrophy) – Once filled to capacity, stimulate the production of more fat cells (hyperplasia) Figure 15.2-The Formation of Adipocytes Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  The Number of Fat Cells in the Body Never Decreases Average adult has 30 to 50 billion adipocytes, which hold 0.4 to 0.5 micrograms of fat each. – Overweight or obese adults are thought to have larger adipose cells (hold 0.6 to 1.2 micrograms of fat each). – Adipocytes shrink in size with weight loss but the number of cells does not decrease. – After weight loss, small fat cells remain and can easily be filled up again when energy intake is greater than energy output – Fat growth and production of cells continue throughout life, but hyperplasia slows with age. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Fat Cells Can Grow and Shrink Enzymes control the size of fat cells. – Lipoprotein lipase (LPL) increases lipogenesis. – Hormone-sensitive lipase (HSL) stimulates lipolysis. Heavier people have increased LPL activity. Men: LPL more active in visceral, abdominal fat cells Women: LPL activity higher in hips and thighs Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved How Do Genetics and Environment Influence Obesity and Weight Management? Nutrigenomics and epigenetics may influence weight control. – Nutrigenomics: how your genetic makeup interacts with your nutrients in terms of absorption, storage, and digestion – Epigenetics: The changes that may occur in gene activity and gene expression without altering DNA sequence ▪ Food is an epigenetic factor that can cause the DNA-histones to partially unwind and expose inactive gene – While we can’t alter the genetic makeup we are born with, we may be able someday to control the factors that turn obesity genes on or off. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Personalized or Precision Nutrition Concept of adapting food to individual needs Consumers usually respond differently to their diet, which depends on their genetic makeup, lifestyle, and environment By customizing nutrition advice, people may be more motivated to make dietary changes to improve their health and lower their risk of obesity, type 2 diabetes, and heart disease. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved Genetics Can Influence Hunger, Satiety, and Insulin Response Altered genes may determine an individual’s hormonal response in the presence of food, affecting hunger and satiety. Another way activity of the gene can be altered is through “single- nucleotide polymorphism,” or SNPs, which alters the nucleotide sequence Epigenetic and SNPs modifications are believed to affect how people respond to food intake. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved Genetics Can Influence Hunger, Satiety, and Insulin Response Adipocytes secrete the hormone adiponectin. – Improves the body’s response to insulin – Reduces fat accumulation in the liver and muscle – Enhances energy expenditure – Lower in obese individuals and type 2 diabetics than in lean people Genetics may also affect thermogenesis, which affects energy expenditure. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved Genetics Can Influence Hunger, Satiety, and Insulin Response Genetic “set point” theory – Weight control theory that determines body weight – Body fights to remain at a specific body weight and opposes attempts at weight loss – Given the rapid rise in weight in the United States, this theory either isn’t true or the set point is easily overridden. Thrifty genes – Enable individuals to efficiently use food to deposit fat during periods of food abundance in order (feast) to provide for periods of food shortage (famine) ▪ Example, Arizona Pima Indians Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved Genetics Can Influence Hunger, Satiety, and Insulin Response Populations which are genetically prone to being overweight or obese can overcome their genetic predisposition by engaging in regular exercise and eating healthy. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Environmental Factors Can Increase Appetite and Decrease Physical Activity Our current environment makes it easier to have a positive energy balance and gain weight. Environmental factors involved with obesity – Lack of time ▪ Most kilocalorie intake is from foods eaten away from home. ▪ Dining out frequently is associated with a higher BMI. ▪ Individuals who dine out are less likely to choose fruits and vegetables when they order. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Environmental Factors Can Increase Appetite and Decrease Physical Activity Environmental factors involved with obesity – An abundant food supply and portion distortion ▪ People have easier access to food. ▪ People eat or drink more when given larger portions. ▪ People eat or drink more when the food is presented in a larger bowl, plate, or package. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Environmental Factors Can Increase Appetite and Decrease Physical Activity Environmental factors involved with obesity – Lack of physical activity and increased sedentary behavior ▪ People do less manual labor in their jobs. ▪ The more people drive, the less they engage in physical activity. ▪ More time is spent in front of the TV or computer. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved How Can You Lose Weight Healthfully? Avoid fad diets Strive for a reasonable rate of weight loss. – Lose 10 percent of body weight over six months. – Modify diet, physical activity, and behavior. Remember that kilocalories count. – Choose lower kilocalorie foods. – Reduce portion sizes. – Increase kilocalories burned. Eat more vegetables, fruit, and fiber. Avoid mindless eating. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved How Can You Lose Weight Healthfully? Add some protein and fat to meals. – Protein promotes satiety. ▪ Focus on lean protein. – Fat slows movement out of the stomach. ▪ Focus on healthy fats in moderation. ▪ Limit fats high in saturated-fats. Use MyPlate as a weight-loss guide. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved How Can You Lose Weight Healthfully? Increase physical activity to lose weight. – Increases kilocalories burned and displaces sedentary activity – Sixty to 90 minutes daily of moderate-intensity physical activity to aid in weight loss and prevent weight gain – Incorporate cardiorespiratory and strength-training activities. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved How Can You Lose Weight Healthfully? Break bad habits with behavior modification. – Focus on changing eating behaviors that contribute to weight gain or impede weight loss. ▪ Keep a food log. ▪ Control environmental cues that trigger eating when hungry. ▪ Learn how to better manage stress. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  How Can Weight Loss Be Maintained? Successful weight maintainers – Maintain the energy-gap reduction in kilocaloric need to maintain the weight loss. ▪ Reduce kilocalorie intake by decreasing portions and fatty foods. ▪ Eat smaller, more frequent meals; make sure it does not turn into “grazing.” ▪ Maintain a high level of physical activity. – Weekly self-weighing can help individuals maintain their weight loss. ▪ Not suggested if you are at risk of disordered eating, negative body image, mood disorders, or binge eating Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  What is the Healthiest Way to Gain Weight? Gaining weight is challenging for those who are underweight. Goal is to gain muscle, not all fat. Methods to do this – Add 500 kilocalories in addition to daily energy intake. ▪ Adds about one pound of extra body weight per week – Choose more energy-dense foods. – Include regular exercise and resistance training. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  What are the Medical Interventions for Extreme Obesity? Weight-loss medications – Sibutramine (Meridia) ▪ Hunger suppressant – Orlistat (Xenical) ▪ Inhibits fat absorption – Liraglutide (Saxenda) ▪ Injectable drug that stimulates the release of a satiety hormone Evaluate the side effects of all weight loss medications to determine if experiencing these effects are worth taking the drug. Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Weight Loss Surgeries Gastric bypass: most common surgical procedure for obesity in the U.S. – Allows food to bypass the lower stomach and the upper portion of the small intestine Gastric banding – Reduces the size of the stomach with an adjustable silicone band Sleeve gastrectomy – Part of the stomach is removed Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved  Bariatric Surgery Restricts Food Intake Gastric bypass surgery Post surgery – Consume small, frequent meals. – Supplement: Iron, calcium, vitamin B12, and vitamin C Weight loss – Five to 15 lbs per week in the first 2 to 3 months – One to 2 lbs per week after first 6 months Reduction in diabetes (76.8 percent) Improved lipid profiles (70.0%) Elimination of hypertension (61.7% ) Elimination of sleep apnea Copyright © 2019, 2016, 2014 Pearson Education, Inc. All Rights Reserved