Chapter 7: Energy Balance and Obesity Calories In vs. Calories Out-Weight management is related to kcal in vs kcal outDiscuss role of calories in to calories burned in weight management or weight loss-To maintain body weight:oConsume as many kcal as expended in a day-In order to lose weight:oConsume less kcal than what we are expending-To gain weight:oConsume more kcal, expend lesso(BUT workout more for healthy gains)-Overall goal:oGain/maintain muscleoHealthy fat stores Calories In: The Food We EatList characteristics of food that may contribute to excess calorie intake-Fast food (drive through) and convenience foods may contribute excess kcal from:oFat and sugar-Foods that are marketed as low-fat or fat-free can be deceiving. They may have additional kcal added to them (replacement sugars may be lesser in nutrients)-Other reasons for excess kcal:oLarger portion sizes (portion control problem)oEasy to do when we dine out-(((((((DK what healthy portion size is)))))) Calories Out: Energy Expenditure-Individuals vary widely in the number of calories burned each day-However, everybody expends energy or calories in three ways:oResting energy expenditure (REE)oPhysical activityoThermic effect of food (TEF)oAltogether, this is:-Total energy expenditure Components of total energy expenditureList and describe the components of total energy expenditure-Energy metabolism that occurs after waking in the morning, at least 12 hours after the last meal:oBasal Metabolic RateoIncludes energy for functions that sustain life:- Breathing- Heart beat- Brain (while sleeping too)- Liver- Kidneys- filtering blood-Less restrictive measure of calories burned while just sitting or sleeping and also make up most of the calories we burnin a day (BMR but less restrictive):o Resting Energy Expenditure (REE)-((((((((((((requires 12 hour fast)))))))))))))) Components of Total Energy Expenditure-Energy expenditure through voluntary physical effort, including daily activities, exercise, or physical labor:oPhysical activity-Energy needed for muscle contraction. oThe more muscles you contract and the more frequently you contract them, the more calories you burnList the factors that may influence the amount of energy expended during exercise-Factors that influence energy burned during exercise:oBody weight and muscle mass in useoDuration of activityoIntensity of the activityoExerciser’s fitness leveloType of activity determines how much energy is used-(((((((((((((planned and unplanned (muscle contraction)))))))))))))))) Components of Total Energy Expenditure-The process of burning calories as you digest, absorb, transport, store, and metabolize food (fairly constant):oThermic Effect of Food (TEF) oResearch shows that your body burns about 10 percent of calories consumed, depending on the type and quantity of food eaten. Diet can have a mild influence:o A little higher for protein (about 10%)o A little lower for fato((((((((((((((Look at 7.4 but don't need to memorize, of three components, we have the most influence overphysical activity)))))))))))))))) Total Energy ExpenditureoTEE estimated by energy equation formulas and factors based on level of physical activity:oWomen: 665.1 + (9.563 x weight in kg) + (1.850 x height in cm) − (4.676 x age) oMen: 66.5 + (13.75 x weight in kg) + (5.003 x height in cm) − (6.775 x age) oMultiply for physical activity factor (Table 7.5)oSedentary: BMR x 1.2 oLightly active (light exercise 1–3 days/week): BMR x 1.37 oModerately active (moderate exercise 3–5 days/week): BMR x 1.55oVery active (hard exercise 6–7 days a week): BMR x1.725 oExtra active (very hard exercise and physical job): BMR x 1.9 o(((((Don't need to memorize formulas, they calculate REE, then plug value in physical activity factor)))))) Total Energy ExpenditureCompare the differences between the components of total energy expenditure between a sedentary and physically active person Body Mass Index (BMI)Define BMI and determine if an individual is considered underweight, normal weight, overweight or obese based on their BMIoThe body mass index (BMI) is a measure of weight relative to height. Often used to diagnose overweight or obesityoStandard formula to calculate BMI:oWeight in kilograms /(height in meters) squaredDiscuss the relationship between BMI and the location of excess body fatoResult may suggest degree of excess body fat:oUnder 18.5: underweighto18.5 – 24.9: normal weighto25 – 29.5: overweightoOver 30: obese BMI and Disease RiskList conditions that the risk for increases in those who are overweight and underweightoBeing overweight or obese raises the risk for a number of diseases, such as: oCardiovascular diseaseoHypertensionoType 2 diabetesoStrokeoGallbladder diseaseoOsteoarthritisoSleep apneaoRespiratory problemsoEndometrial, breast, prostate, and colon cancers BMI and MortalityDiscuss the risk of chronic conditions and mortality UnderweightoA BMI < 18.5 kg/m2 is considered to be:oUnderweightoNegative consequences of being underweight may include:oDecreased overall energyoRespiratory complicationsoHeart irregularitiesoInfertilityoWeakened immune systemoDelayed wound healingo… UnderweightDefine osteoporosis and list the risk factors for developing osteoporosisoA condition associated with decreased bone mass and bone density that can result in increased risked of bone fracture is:oOsteoporosisoThose at greater risk for osteoporosis includes:o…o…o…o…o… Identify individuals for whom BMI may not accurate screen for overweight or obesityLimitations of BMIoLimitations of BMI fails:oDoes not distinguish between fat and muscle mass-Taking into account height and weight (?)oOther ethnicitiesoElderlyoSex - male/female Body Composition oTotal body mass is the sum of lean tissue mass, fat mass and wateroThere are categories of body fat:oThe fat required for normal physiological functioning-Essential fatoFat from adipose tissue, tissue under the skin, and the fat that “pads” essential organs-Storage fatoPercent of weight from fat differs with age and sex:oBody fat usually increases with ageoWomen should have a higher body fat percentage than menBody CompositionoFat : women have higher body mass percentage (pregnancy)oMuscle: men have higher body mass percentageoBone: men have higher body mass percentage (taller) Body Fat DistributionoThere are two kinds of distributions:oGynoid pattern (pear shape)-Fat over the muscle and under the skin at hips and