CONCEPTS OF OBESITY NURS: 2018, Diet Therapy

Objectives At the end of this presentation students should be able to: Describe the concept of desirable body weight relative to age, gender, and developmental variables Use the concept of desirable weight in meeting the nutritional needs of individuals State the socio-cultural, genetic, emotional, and lifestyle factors which contribute to obesity Discuss principles of effective treatment of obesity

Objectives Plan a modified calorie diet based on diet prescription for specified weight loss Identify strategies for obesity prevention Name the characteristics of effective obesity intervention approaches Discuss current research in obesity therapy

Multi-factorial influence on obesity

Factors influencing appetite InfluenceExamples CognitiveRestraint, emotions, previous experience, conditioned associations Socio-culturalReligious beliefs, education, tradition, learned experiences, economy-acquisition level GustatoryPalatability, learned/innate preferences, food-specific satiety, nutrient-associated sensory stimuli, cephalic phase events NeuroendocrineOrixegenic and anorexigenic peptides, entero-insular axis, adipostatic signals, sympathetic/paarsympathetic balance GastrointestinalNutrient composition, water content, energy density, digestibility, pH, osmolarity, peptidic/hormonal/neural release, stomach size, mechanical distension, emptying rate, absorption MetabolicNutrient partitioning/flux, nutrient genotype interactions, hepatic metabolism BehaviouralAge, sex, socioeconomic status, occupation, meal patterns, physical activity level, pathophysiology/developmental stage Fruhbeck, 2006

Terms in weight management Normal weight- persons having BMI kg/m 2 Overweight-adults with BMI between 25 and 29.9 kg/m 2 Obesity- adults with BMI greater than 30 kg/m 2 Obesity is a condition in which fat stores (adiposity) are excessive for an individual’s height, weight, gender and race to the extent that it produces adverse health outcomes.

Terms in weight management Underweight- adults with a BMI below 18.5 kg/m 2 For children, aged, or very fit and muscular, BMI definitions are not useful as obesity measure.

Variables that are important to Weight Age- affects body composition and the presence of muscle and fat. BMI is a measure of weight unaffected by height.  Older adults have more fat and less muscle mass due to effects of aging and sarcopenia;  children have less muscle because of developmental changes.

Variables that are important to Weight Gender affects body composition.  Males generally have higher muscle content than females and may have higher assessed levels of BMI Body Composition Exercise leads to loss of fat mass and may overtime result in higher lean body mass with resultant higher BMI.

Types of obesity Defining Obesity based on causal factors Simple obesity (alimentary obesity) – this happens when a person consumes more kilojoules than the body can utilise, and accounts for approximately 95% of obesity cases. Secondary obesity results from underlying medical conditions such as Cushing’s syndrome, polycystic ovary syndrome, and insulin tumours. Other conditions can also cause secondary obesity.

Types of obesity Defining Obesity based on causal factors Childhood obesity – when children and adolescents are above the normal body weight for their height and age. Obese children are at risk for long-term problems such as diabetes, hypertension, thyroid problems, and high cholesterol. Even though these health complications are more common among adults, they can still affect children. Obesity can affect a child’s normal growth and development.

Types of Obesity Obesity may also be defined based on WHO classifications and BMI cut-off points. ClassificationBMI (kg/M 2) Underweight<18.5 Normal weight Moderate overweight Overweight≥25.0 Preobese Obesity≥30 Obese class I Obese class II Obese class III≥40 Seidell & Visscher, 2004

Treatment Goal of obesity treatment is to :- Reduce morbidity and mortality risk and to improve cardiovascular health Reduce the burden on the health care sector Improve the productive sector  Tucker & Dauffenbach, 2011

Goals of obesity Therapy Weight loss- set realistic goals that are achieved in stages Change in body shape and size- (less abdominal and intra-abdominal fat) Control of associated disorders:  Impaired glucose metabolism (diabetes, impaired glucose tolerance)  Dyslipidaemia  Hypertension  Sleep apnoea  Arthrititis Mobility Reduction in medications Improved cardiovascular fitness Improved psychological and social factors Attainment of individual goals  Fitting into clothes  Need for, ability to have operation  Reduction in pain (Omari & Caterson, 2007)

Treatment Modalities Lifestyle modifications  Diet  Physical activity  Behaviour modification Weight loss is more likely sustained if individuals who engage in non-surgical measures continue to engage in these activities after 10% weight loss is seen. Weight loss strategies are not suitable for every group.  Children- care take to maintain weight except if BMI is 95 th percentile or above  Pregnant women- contraindicated; for obese women recommended gain is pounds  Older persons- age does not preclude persons; care needs to be taken to preserve lean body mass

Treatment Modalities Lifestyle Modifications  Diet  Weight loss occurs when calorie expenditure exceeds intake.  Dietary manipulations are the subject of many research but the data is unclear at this time; consistent is the information that calorie restriction rather than macronutrient manipulation has some effect.

Treatment Modalities- Low Calorie Diets DietDefinitionRisks and benefits StarvationLess than or equal to 200 kcalLoss of fluid and electrolytes, esp. K; inadequate nutrient intake, muscle loss Very low calorie kcal, liquid or solid; includes formal programs at medical centre and some weight loss centers Loss of fluid and electrolytes, esp. K; inadequate nutrient intake, muscle loss may occur, used under medical supervision for extreme obesity Low calorieReduced cal compared to usual; liquid or solid; includes formal programs at medical centre and some weight loss centers and meal replacement drinks and packaged foods Can be nutritionally balanced if all the food groups are included; meal replacement foods are not conducive to learning permanent new food behaviors Tucker & Dauffenbach, 2011

Treatment Modalities- Nutrient Altered Diets DietDefinitionRisks and benefits Low carbohydrate Less than or equal to 100gm carbohydrate/d Ketosis, often high fat, forbidden foods lead to inadequate nutrient intake, low fibre, may or may not have reduced carbohydrate Moderate fat, moderate to high carbohydrate Greater than 50% of calories as carbohydrates and 25-35% as fat Generally balanced nutrients; may or may not be reduced calorie Low fat or very low fat Less than 25% calories as fat and high carbohydrate with high fibre Increased carbohydrate can lead to high triglycerides, high volume of fibre may lead to malabsorption of some nutrients; too may low fat can lead to low HDL cholesterol and essential fats; may or may not be reduced calorie Tucker & Dauffenbach, 2011

Treatment Modalities- Novelty Diets DietDefinitionRisks and benefits Single FoodFocus on food as contributing to weight loss (e.g. grapefruit, vinegar or cabbage soup) Inadequate nutrient intake if only single food is ingested; boredom and lack of lifestyle management; reduced calorie only because of limiting nature of foods Fo0d combining Foods are eaten in set combinations felt to cause weight loss (e.g. fruit eaten only with proteins and vegetables with grains, specific foods recommended for body or blood type). Some diets lack food groups and, therefore, are nutritionally inadequate. No specific evidence of magic to food combining; often reduced calorie because of limited intake. Tucker & Dauffenbach, 2011

Outline for Obesity Intervention BMIGeneral Advise Lifestyle programme Adjunctive Therapy Possibilities Maintain weight Use High Risk*UseConsiderPharmacotherapy UseConsider/usePharmacotherapy or VLCDs High Risk*Use Pharmacotherapy +/- VLCDs Use Pharmacotherapy +/- VLCDs High Risk *Use Pharmacotherapy + VLCDs or surgery 40 +Use Pharmacotherapy + VLCDs or surgery

References Frühbeck, G. (2006). Overnutrition. In M., Gibney, M. Elia, O., Ljungqvist, & J., Dowsett (Eds.), Clinical Nutrition. (pp ). Oxford, UK: Blackwell Science Ltd. Omari, A. & Caterson, I. D. (2007). Overweight and obesity. In J. Mann & A. S. Truswell (Eds.), Essentials of human nutrition (3 rd Ed.). (pp ). New York, USA: Oxford University Press. Seidell, J. C. & Visscher, T. L. S. (2004). Public health aspects of overnutrition. In M., Gibney, M. Elia, O., Ljungqvist, & J., Dowsett (Eds.), Public Health Nutrition. (pp ). Oxford, UK: Blackwell Science Ltd. Tucker, S. & Dauffenbach, V. (2011). Nutrition and diet therapy for nurses. Boston, USA: Pearson.