Nutrition Chp 10: ENERGY BALANCE
Weight control objectives from Healthy People 2020
-Reduce the proportion of adults who are obese -Reduce proportion of children/adolescents that are obese -increase the proportion of physician office visits that include counseling or education related to nutrition or weight
Environmental factors may define what in relation to eating
-When eating is appropriate -What is preferable to eat -how much food should be eaten
Hormones that encourage the storage of fat in the lower body
-estrogen -progesterone
Environmental factors affecting our food choices
-food availability and preferences, food marketing, social networks, culture, education, lifestyle, health concerns, and income
Factors that increase basal metabolism
-greater muscle mass** most important one -larger body surface area -male gender -body temp -higher than normal secretions of thyroid hormones -aspects of nervous system activity -growth stages of the life cycle -caffeine and tobacco use -recent exercise
What encourages upper body fat storage?
-high blood testosterone levels -high glycemic diet -alcohol intake -smoking
Effects of anorexia
-low body weight -lowered body temp and cold intolerance -slower metabolic rate -decreased heart rate -iron deficiency anemia -rough, dry, scaly, cold skin -low white blood cell count -abnormal feel of fullness or bloating -loss of hair -appearance of lango (downy hairs that appear on the body after a person has lost much body fat through semistarvation -constipation -low blood potassium -loss of menstrual periods -changes in neurotransmitter function in brain leading to depression -eventual loss of teeth -muscle tears and stress fractures in athletes
Waist circumference for males and females that is considered obese
-males: 40 inches -females: 35 inches
Drug treatment options for weight loss
-meds that enhance norepinephrine and serotonin activity in the brain -Fastin or lonamin which prolongs epinephrine and norepinephrine activity in the brain... -meds that inhibit lipase enzyme action in the small intestine -certain antidepressants
Most notable low fat diets
-pritikin diet -dr. dean ornish's eat more -weigh less plans
criteria for diagnosing bulimia nervosa
-recurrent episodes of binge eating -recurrent inappropriate compensatory behavior to prevent weight gain -binge-eating episodes -undue influence of body weight or shape on self-evaluation -disturbance does not occur exclusively during episodes of anorexia nervosa
criteria for diagnosing anorexia
-refusal to maintain body weight at or above a minimally normal weight for age and height -intense fear of gaining weight or becoming fat even though underweight -disturbance in the way in which one's body weight or shape is experienced -amenorrhea (absence of at least 3 consecutive menstrual cycles in females who have passed puberty
Health problems associated with bulimia nervosa
-repeated exposure of teeth to the acid in vomit -blood potassium drops -salivary glands may swell -stomach ulcers and tears in the esophagus develop -constipation may result -ipecac syrup which is sometimes used to induce vomiting is toxic to the heart, liver, kidneys, and can cause accidental poisoning when taken repeatedly
A rough estimate of basal metabolic rate for women and men
.9 kcal per hour for women 1 kcal an hour for men
Equations to calculate BMI
1) body weight (kg)/ height (m) 2)body weight in lbs x 703/height in inches
The three main purposes that the body uses energy for
1- basal metabolism 2- physical activity 3-digestion, absorption, and processing of ingested nutrients
Basal metabolism drops ?% for each decade past the age of 30 years as a result of lean body mass loss that typically occurs with advancing age
1-2%
10 red flags of diet/nutrition
1-recommendations that promise a "quick fix" 2-dire warnings of danger from a single product or regimen 3-claims that sound too good to be true 4- simplistic conclusions drawn from a complex study 5-recommendations based on a single study 6-dramatic statements that are refuted by reputable scientific organizations 7-lists of good and bad foods 8-recommendations made to help sell a product, often testimonials are used 9-recommendations based on studies published without peer review 10-recommendations from studies that ignore differences among individuals/groups
National Weight Registry 4 behaviors for successful maintainers
1. Eat a low fat, high-carb diet 2. Eat breakfast 3. Self-monitor by regularly weighting oneself and keeping a food journal 4. Have a physical activity plan
The three 3 key components of a sound weight-loss program
1. control of energy intake 2. Regular physical activity 3. control of problem behaviors
Three techniques used to assess body fat
1. skinfold thickness 2. bioelectrical impedance 3. dual energy x-ray absorptiometry
About ?% of cases of bulimia nervosa occur in men
10%
Basal metabolism decreases by ?% per day when calorie intake declines and the body shifts into a conservation mode
10-20% per day..this shift helps us survive during periods of famine and starvation
A BMI of what is an indicator of aneroxia
17.5 or less
BMI for underweight individuals
18.5
A healthy weight-for-height BMI range
18.5 to <25
body fat can range from 2 to ?% of body weight
2-70% of body weight
how many lbs for every kg
2.2lbs
Physical activity increases energy expenditure above and beyond basal energy needs by as much as ?%
25-40%
How much do americans spend yearly on fad diets
33 billion
Adipose tissue (mostly fat) contains ?kcal/lb
3500 kcal/lb
Up to what % of adolescent and college-age women suffer from bulimia nervosa
4
Genes account for what % of weight difference between people
40-70%
During infancy, brown fat is most important and accounts for ?% of weight and is important for what?
5 %, thermoregulation
What percent of women in North America develop some form of anorexia nervosa or bulimia nervosa in their lifetimes
5%
The TEF accounts for ?% of energy consumed each day
5-10%
low fat diets contain ?% energy intake as fat
5-10%
About what % of people with bulimia nervosa recover completely from the disorder
50%
What % of people with eating disorders fall into this category
50% of people (esp adolescents)
To lose one lb of adipose tissue per week, energy must be decreased by ?kcal/day or physical activity must be increased by ?kcal per day
500 kcal
How much more common are eating disorders in females than males
6 to 10 times more common
The RMR is typically ?% higher than the BMR?
6%
For a sedentary person, basal metabolism accounts for about ? % of total energy expenditure
60-70%
lean body tissue is about ?% water
70% water
Hospitalization is necessary once a person falls below what % of expected weight
75%
In gastroplasy, what % of people with severe obesity eventually lose half or more of their excess body weight?
75%
When laxatives or enemas are used, about ?% of the energy is absorbed bc these products at in the large intestine beyond the point of most nutrient absorption
90%
A "thrifty metabolism"
A metabolism that uses energy frugally...enables them to store fat readily and use less energy to preform tasks than regular individuals
Characterized by extreme weight loss, a distorted body image, and an irrational, almost morbid fear of obesity and weight gain. Individuals believe they are fat even though they are not and others tell them so
Anorexia nervosa
The preferred weight-for-height standard bc it more closely is related to body fat content
BMI Body Mass Index
The minimum amount of energy expended in a fasting state (12 hours or more) to keep a resting, awake body alive in a warm, quiet environment
Basal metabolism (basal metabolic rate) (BMR)
Diet plans that use the "low-carb" approach
Dr. Atkins' New Diet Revolution, the Scarsdale Diet, the 4-day wonder diet...moderate approaches found in the South Beach, Zone, and Sugar Busters Diets
The most accurate way to determine body fat (1-4 % margin of error) but equipment is very expensive and not widely available..whole body scan takes 5-10 minutes and the dose of radiation is less than a chest x-ray...Can estimate body fat, fat-free soft tissue, and bone minerals
Dual energy x-ray absorptiometry (DEXA)
A broad category of eating disorders in which individuals have partial syndromes that do not meet the strict criteria for anorexia nervosa or bulimia nervosa
EDNOS Eating Disorders Not Otherwise Specified
measurements based on formulas developed by the food and nutrition board that can estimate energy needs using a person's weight, height, gender, age, and physical activity level
Estimated Energy Requirement (EER)
The contribution of nature (genetics) to body weight through the study of twins
Even when identical twins are raised apart, they tend to show similar weight gain patterns both in overall weight and overall fat distribution...nurture has less to do with weight-gain patterns that nature does
Claim miraculous weight loss or improved health--often by unhealthy or unrealistic eating plans
Fad diets
low carb diets increase
LDL cholesterol
A genetic disorder affecting muscles and skeleton, characterized by tallness, long arms, and little subcutaneous fat.
Marfan Syndrome
Does aging cause weight gain?
No, it stems from a pattern of excess food intake coupled with limited physical and a slower metabolism
Has drug therapy alone been successful for weight loss?
No...success with medication has only been shown in those who also modify their behavior, decrease their energy intake, and increase their physical activity
The theory that proposes that humans have a genetically predetermined body weight/body fat content which the body closely regulates...it is not known what cells control this or how it actually functions in weight regulation
Set Point theory
When determining if a person's weight is healthy, what factors should be considered?
Total amount of body fat Location of body fat Presence or absence of weight-related medical problems
Modified fasts used to treat severe obesity if more traditional dietary changes have failed...provide 400-800 cals daily often in liquid form and tend to be used if a person has an obesity-related condition that is not well controlled....half cals carbs, half cals protein...major health probs are heart problems and gallstones
Very-low-calorie diets (VLCDs)
Device that directly measures calorie content
a bomb calorimeter
what is satiety
a state of satisfaction where we no longer have the drive to eat
What percent of people who follow commercial diet programs actually lose weight AND remain close to that weight?
about 5%
At what life stage do eating disorders develop 85% of the time
adolescence or early adulthood
A method that measures body volume by measuring the space a person takes up inside a small chamber such as a "bod pod"
air displacement
the main types of eating disorders
anorexia nervosa bulimia nervosa eating disorder not otherwise specified
What is more common...the cross from anorexia to bulimia or bulimia to anorexia
anorexia to bulimia
the psychological drive to eat...is affected by mostly external factors that encourage us to eat such as social custom, time of day, mood, memories of pleasant tastes, and the sight of a tempting dessert
appetite
among men, who are the most likely to develop anorexia
athletes
a vertical staple line is made down the center of the stomach to create a small pouch...at the pouch outlet, a band is placed to keep the opening from stretching. A band is placed to create a small stomach pouch. A salt solution can be injected into the band through a port
banded gastroplasty
Why does indirect calorimetry work?
bc a predictable relationship exists between the body's use of energy and the amount of oxygen consumed and carbon dioxide produced.
Why does direct calorimetry work? Is it used frequently ?
bc almost all of the energy the body uses eventually leaves as heat...no it is not used frequently bc it is expensive and complex to use
Why is the TEF value higher for a protein rich meal?
bc it takes more energy to metabolize amino acids into fat than to convert glucose into glycogen or transfer absorbed fat into adipose stores
How is weight loss achieved with gastroplasty
bc most of the food bypasses the stomach and small intestine which results in less digestion and absorption of nutrients
Why do low energy dense foods like those high in water and fiber increase satiety
bc they expand the stomach and intestine to a greater extent than light-weight foods
Why do women need more body fat?
because some "sex-specific" fat is associated with reproductive functions
Estimates body fat content by sending a painless, low-energy electrical current through the body...researchers guess that adipose tissue resists electrical flow more than lean tissue does bc adipose tissue contains less electrolytes and water than lean tissue thus greater electrical resistance is associated with more adipose tissue..3-4% margin for error IF patient has prepared by having normal body hydration, resting for 12 hours, fasting for 4 hours, and not drinking alcohol for 48 hours before the test
bioelectrical impedance
The regulation of food intake and satiety is complex and involves
body cells (brain, adipose tissue, stomach, intestines, liver, and other organs), hormones (eg. cholecystokinin and gherkin), neurotransmitters (eg. serotonin), dietary components, and social customs
body density =
body weight / body volume
A specialized form of fat tissue that participates in thermogenesis...it releases much of the energy from energy yielding nutrients as heat
brown adipose tissue
Characterized by episodes of binge eating followed by attempts to purge the excess energy consumed by vomiting or misusing lazatives, diuretics, or enemas
bulimia nervosa
Low fat diets tend to be high in
carbs
separates the link between behaviors that tend to occur together like snacking on chips while watching television
chain-breaking
by the release of the neurotransmitter histamine which affects the satiety center in the brain this mechanism contributes to satiety
chewing
changes one's frame of mind regarding eating--for example, instead of using a difficult day as an excuse to overeat, substitute it for another positive reward, such as a relaxing walk with a friend
cognitive restructuring
prepares one for situations that may trigger overeating or hinder physical activity
contingency management
What is the first goal in treatment for bulimia nervosa
decrease the amount of food consumed in a binge session in order to reduce the risk of esophageal tears from related purging by vomiting
When energy intake is reduced, secretions of the thyroid hormone
decrease/fall which slows basal metabolism and conserves body weight
What are novelty diets...examples
diets that are built on gimmicks...some emphasize one food/food group and exclude all others...ex: Fit for Life, Beverly Hills diet, Eat Great lose weight
Estimates the energy expenditure by measuring the amount of body heat released by a person
direct calorimetry
mild and short term changes in eating patterns that occur in response to a stressful event, an illness, or a desire to modify the diet for healthy and/or personal appearance
disordered eating
The relationship between energy intake and energy expenditure
energy balance
When the calories consumed match the amount of energy expended
energy equilibrium
Recommended to those who are morbidly obese, have been obese for at least 5 years with several nonsurgical attempts to lose weight, and have no history of alcoholism or major psych disorders...works by reducing the stomach capacity to about 30 ml and bypassing a short segment of the upper small intestine
gastroplasty
hormone made by the stomach that increases food intake
ghrelin
Overweight and obese people should emphasize what kind of lifestyles?
healthy, active lifestyles with lifelong dietary modifications
the physiological drive to find and eat food...controlled primarily by internal body mechanisms such as organs, hormones, hormone like factors, and the nervous system
hunger
The two factors that drive our desire to eat
hunger and appetite
adipose cells can also make substances that can...
increase inflammation, insulin resistance, blood clotting, and blood vessel constriction
The most commonly used method to determine energy use by the body...involves collecting expired air from an individual during a specified amount of time
indirect calorimetry
What accounts for the major part of the weight lost when weight loss exceeds a few lbs a week
lean tissue and water
A hormone produced by the adipose tissue that influences long-term regulation of fat mass
leptin
Health risks of being underweight
loss of menstrual function low bone mass complications with pregnancy and surgery slow recovery after illness
EER formula for male and female
male: 662-(9.53 x AGE) + PA X (15.91 X WT) + 539.6 X HT female: 354-(6.91 X AGE) + PA X (9.36 X WT) + (726 X HT) *** PA = PHYSICAL ACTIVITY ESTIMATE ***WT = WEIGHT IN KG (LBS / 2.2
A goal of losing 1 lb or so of stored fat per week may require limiting energy intake to what for men and what for women
men: 1500kcal/day women: 1200kcal/day
desirable amounts of body fat for men and women
men: 8-24% of body weight women:21-35% of body weight
A condition characterized by an excessive concern that one has underdeveloped muscles...spend a lot of time lifting weights
muscle dysmorphia
Results when energy intake is less than energy expenditure
negative energy balance; accompanied by weight loss bc energy stored in the body is used to make up for the shortfall in energy intake
Percent chance of child being obese if... -no obese parents -1 obese parent -2 obese parents
no obese parents: 10% 1 obese parent: 40% 2 obese parents: 80%
the "health food eating disorder" ...people with this spend hours each day finding foods that are "pure"
orthorexia
What maintains lean body mass and helps preserve BMR throughout adulthood
physical activity
If energy intake exceeds energy expended
positive energy balance; energy is stored resulting in weight gain
keeping low-fat snacks on hand to satisfy hunger/appetitie or placing walking shoes in a convenient visible location
positive stimulus
Genetic disorder characterized by shortness, mental retardation, and uncontrolled appetite caused by a dysfunction of the nervous system, leading to extreme obesity
prader-willi syndrome
When is positive energy balance desired?
pregnancy, infancy, childhood, and adolescence and to restore body weight to healthy levels after losses caused by starvation, disease, or injury
describes women who decrease calories and exercise excessively to control weight gain during pregnancy
pregorexia
low carb diets lead to reduced glycogen synthesis and therefore
reduced amounts of water in the body (3 gram glycogen for every one gram of water)
Instead of emptying fat directly into general circulation like other adipose cells, abdominal adipose cells....
release fat directly into the liver by way of the portal vein
If the person is not fasting or completely rested what term describes their metabolism
resting metabolism (resting metabolic rate) (RMR)
tracks which foods are eaten when why how one feels which physical activities are completed and body weight. Self-monitoring helps people understand more about their habits and reveals patterns such as unconscious overeating that may explain problem behaviors that lead to weight gain
self-monitoring
weighing at least 100 lbs over healthy body weight or twice one's healthy body weight
severe (morbid) obesity
dumping syndrome
severe diarrhea that begins almost immediately after eating concentrated sugar such as regular soft drinks, candy, and cookies
A common anthropometric method to estimate total body fat content...technicians use calipers to measure the fat layer directly under the skin at multiple sites and then enter those values into a mathematical formula. The accuracy is good (3-4% error margin)
skinfold thickness
Alters the environment to minimize the stimuli for eating--for example, storing foods out of sight and avoiding the path by the vending machines
stimulus control
What factors cause dieting to get out of control
stress, lack of appropriate coping mechanisms, dysfunctional family relationships, and drug abuse
Currently only what approaches to obesity treatment routinely show success in maintaining the weight loss in most people
surgical approaches
Part of the nervous system that regulates involuntary vital functions, including the activity of the heart muscle, smooth muscle, and adrenal glands
sympathetic nervous system
Basal metabolism does not include
the energy expended for physical activity or the digestion, absorption, and processing of nutrients recently consumed
When weight is lost, the body becomes more efficient at storing fat by increasing the activity of
the enzyme lipoprotein lipase, which takes fat into cells
What communicates with the endocrine and nervous systems and integrates many internal cues including blood glucose levels, hormone secretions, and sympathetic nervous system activity that both inhibit and encourage food intake
the hypothalamus
The major lifestyle changes that gastroplasty requires
the need for frequent, small meals...the elimination of sugars from the diet.
The energy the body uses to digest, absorb, transport, store, and metabolize the nutrients consumed in the diet
thermic effect of food (TEF)
The process of heat production by humans and other organisms...makes a fairly small contribution to overall energy expenditure
thermogenesis
a fourth minor form of energy output where the energy is expended during fidgeting or shivering in response to cold
thermogenesis
First goal of nutrition therapy
to gain the patient's cooperation and trust in order to increase oral food intake
Brown fat has a protein that uses the food we consume to do what instead of creating energy in the form of ATP
to generate heat for the body
One of the most accurate measures of body volume...determines body volume by measuring body weight while underwater and body weight in air and entering these values into a mathematical formula that accounts for the differences in the relative densities of fat tissue and lean tissue
underwater weighing
This kind of obesity is more related to cardiovascular disease, hypertension, and type 2 diabetes...
upper-body (android) obesity
When is adaptive thermogenesis heat produced?
when the body expends energy for non voluntary activities including fidgeting, shivering when cold, maintaining muscle tone, and holding the body up when not lying down
