Chapter 10 - Energy Balance, Weight Control, and Eating Disorders Flashcards
Energy Balance
State in which energy intake, in the form of food and beverages, matches energy expended, primarily through basal metabolism and physical activity
Equilibrium
In nutrition, a sate in which nutrient intake equals nutrient losses. Thus, the body maintains a stable condition, such as energy equilibrium.
Positive Energy Balance
State in which energy intake is greater than energy expended, generally resulting in weight gain
When is positive energy balance desired?
During pregnancy, infancy, childhood, adolescence, and after losses due to starvation, disease, or injury.
Negative Energy Balance
State in which energy intake is less than energy expended, resulting in weight loss
When is negative energy balance desired?
It’s desired in adults when their body fatness exceeds healthy levels.
Basal Metabolism
Minimum amount of energy the body uses to support itself when fasting, resting, and awake in a warm, quiet environment. Expressed as basal metabolic rate (BMR)
Basal metabolism accounts for how much of the body’s total energy expenditure?
60-70%
Resting Metabolism
Amount of energy the body uses when the person hasn’t eaten in four hours and is resting and awake in a warm, quiet environment. Expressed as resting metabolic rate (RMR)
How much higher is the RMR than the BMR?
typically 6% higher
What are the factors that increase basal metabolism? (9 things)
- greater muscle mass
- larger body surface area
- male gender
- body temperature
- higher than normal thyroid hormone secretions
- nervous system activity
- growth stages of the life cycle
- caffeine and tobacco use
- recent exercise
Of the factors that increase basal metabolism, which is the most important?
Greater muscle mass
What are the factors that decrease basal metabolism? (4 things)
- lower than normal thyroid hormone secretions
- restricted calorie intake
- less body surface area and muscle mass
- aging after age 30
Physical activity increases energy expenditure above basal energy needs by how much?
25-40%
Thermic Effect of Food (TEF)
Energy the body uses to digest, absorb, transport, store, and metabolize nutrients
TEF accounts for how much energy consumed each day?
5-10%
Thermogenesis
Heat production by humans. Produced when the body expends energy for involuntary physical activity triggered by cold conditions or overeating.
What type of tissue releases much of its energy from energy-yielding nutrients as heat and why?
Brown adipose tissue; it has an uncoupling protein that causes this
Direct Calorimetry
Method of determining a body’s energy use by measuring heat that is released from the body, usually using an insulated chamber
Indirect Calorimetry
Method to measure energy use by the body by measuring oxygen uptake. Formulas are used to convert this gas exchange value into energy use.
What is the most commonly used measurement of energy use?
Indirect Calorimetry
How do you determine the EER of a male older than 19?
EER = 662 - (9.53 x age) + physical activity estimate x ([15.91 x weight (kg)] + [593.6 x height (m)])
How do you determine the EER of a female older than 19?
EER = 354 - (6.91 x age) + physical activity estimate x ([9.36 x weight (kg)] + [726 x height (m)])
Satiety
State in which there is no longer a desire to eat; feeling of satisfaction
Sympathetic Nervous System
Part of the nervous system that regulates involuntary vital functions, including the heart muscle, smooth muscle, and adrenal glands
What is the process of satiety? (4 steps)
- Flavor of food
- Knowing a meal was just eaten
- Influence of stomach and intestinal expansion and activity
- Influence of nutrient use in the liver and related communication with the hypothalamus and other regions of the brain
Ghrelin
Hormone made by the stomach that increases food intake
Leptin
Hormone made by adipose tissue that influences long term regulation of fat mass
Body Mass Index (BMI) Calculation
BMI = (body weight (lb) x 703)/height (in.)^2
What is the healthy range for BMI?
18.5 to 25
What is the desirable amount of body fat for men?
8-24%
What is the desirable amount of body fat for women?
21-35%
Underwater Weighing
Method of estimating total body fat by weighing the individual on a standard scale and then weighing them again submerged in water. The difference between the two weights is used to estimate total body volume.
Air Displacement
Method for estimating body composition based on the volume of space taken up by a body inside a small chamber
Body density = Body weight/Body volume
Skinfold Thickness
Method for estimating body composition by measuring fat just under the skin (subcutaneous) with skinfold calipers and then using the measurement in a mathematical formula to estimate body fat
Bioelectrical Impedance
Method to estimate total body fat that uses a low energy electrical current. The more fat storage a person has, the more impedance (resistance) to electrical flow will be exhibited
Dual Energy Xray Absorptiometry (DEXA)
Highly accurate method of measuring body composition and bone mass and density using multiple low energy Xrays
Genes account for how much of the weight differences between people?
40-70%
Set-Point Theory
Proposes that humans have a genetically predetermined body weight or fat content that’s closely regulated
Marfan Syndrome
Genetic Disorder affecting muscles and skeleton, characterized by tallness, long arms, and little subcutaneous fat
Prader-Willi Syndrome
Genetic disorder characterized by shortness, mental retardation, and uncontrolled appetite, caused by a dysfunction of the nervous system, leading to extreme obesity
What are the 3 key components of a good weight loss program?
- Control energy intake
- Regular physical activity
- Control of problem behavior
How many kcal/lb does adipose tissue contain?
3500
In order to lose one pound a week, by how much would you have to decrease your energy intake each day?
500 kcal
In order to lose one pound a week, by how much would you have to increase your energy expenditure each day?
500 kcal
Chain-Breaking
Breaking the link between two or more behaviors that encourage overeating, such as snacking while watching TV
Stimulus Control
Alteration of the environment to minimize the stimuli for eating, such as removing foods from sight and storing them in the kitchen cabinets
Cognitive Restructuring
Changing one’s frame of mind regarding eating. For example, instead of using a difficult day as an excuse to overeat, substitute other pleasures or rewards.
Contingency Management
Forming a plan of action to respond to a situation in which overeating is likely, such as when snacks are within reach at a party
Self-Monitoring
Tracking behavior and conditions affecting that behavior
What are the 10 red flags for diets?
- Promises a quick fix
- Warnings of danger from a single product/regimen
- Sounds too good to be true
- Simplistic conclusions from a complex study
- Recommendations based on a single study
- Dramatic statements refuted by reputable scientific organizations
- Lists of “good” and “bad” foods
- Recommendations made to help sell a product (ex: testimonies)
- Recommendations made on a study published without peer review
- Recommendations that ignore the differences among individuals or groups
Very-Low-Calorie Diet (VLCD)
Diet that contains 400-800 kcal per day, often in liquid form. Of this, 120 to 480 kcal are carbs, the rest is mostly high quality protein.
AKA protein-sparing modified fast (PSMF)
Dumping Syndrome
After gastroplasty, severe diarrhea that begins almost immediately after eating concentrated sugar
Disordered Eating
Mild and short term changes in eating patterns that occur in relation to a stressful event, an illness, or a desire to modify one’s diet for a variety of health and personal appearance reasons
Eating Disorder
Severe alterations in eating patterns linked to physiological changes; the alterations include food restricting, binge eating, purging, weight fluctuations, and emotional and cognitive changes in perceptions of one’s body
Anorexia Nervosa
Eating disorder involving a psychological loss or denial of appetite followed by self-starvation; it’s related, in part, to a distorted body image and social pressures
What is the average recovery time for anorexia nervosa?
7 years
Bulimia Nervosa
Eating disorder in which large quantities of food are eaten at one time (binge eating) and counteracted by purging food from the body, fasting, and/or exercising excessively
Binge-Eating Disorder
Eating disorder characterized by recurrent binge eating and feelings of loss of control over eating
Amenorrhea
Absence of at least 3 menstrual cycles in females who have passed puberty
Lanugo
Downy hairs that appear on the body after a person has lost much body fat through semi-starvation
Eating Disorders Not Otherwise Specified (EDNOS)
Eating disorder that doesn’t meet the criteria for anorexia nervosa or bulimia nervosa
Muscle Dysmorphia (Bigorexia)
Condition characterized by excessive concern that one has underdeveloped muscles
Orthorexia (Health Food Eating Disorder)
Excessive concern for eating the right foods
Pregorexia
Women who decrease calories and exercise excessively to control weight gain during pregnancy
What are the 5 questions in the SCOFF Eating Disorder Assessment?
- Do you make yourself (S)ick because you feel full?
- Do you lose (C)ontrol over how much you eat?
- Have you lost more than (O)ne stone (~13 lbs) recently?
- Do you believe you’re (F)at when others say you’re thin?
- Does (F)ood dominate your life?
