Term
Healthy Body Weight:
Weight within suggested range for height
Fat distribution associated with low illness or death rate
Free of medical conditions that suggest need for weight loss |
|
Definition
Range of weight for a given height
Within 10-20% above suggested = overweight
Central fat (around center of body (abdomen))
More dangerous - heart problems
≥20% above = obese
≥10% below = underweight |
|
|
Term
|
Definition
weight (kg)/ height2 (m)
=
weight (lb) x 705/height2 (in) |
|
|
Term
|
Definition
Males 10-25%
Females 18-32%
May be lower in athletes:
5-10% males
15-20% females |
|
|
Term
|
Definition
BMI 25.0-29.9 is overweight
Within 10-20% above suggested weight for a given height
BMI ≥30.0 is obese
≥20% above suggested weight for a given height
Extremely overweight |
|
|
Term
|
Definition
Estimated that 68% of Americans are overweight or obese
Estimated 33% of Americans are obese
Estimated that 35-45% of US women and 20-30% of US males are trying to lose weight
Only 2% of those who lose weight have long term success
Lose 10% of weight & kept weight off at least one year |
|
|
Term
|
Definition
Heredity
2) Environment
3) Psychological Stimuli
4) Physiological Problems
5) Physical Inactivity |
|
|
Term
|
Definition
If both parents are obese, ~80% chance of obese children
If neither parent is obese, <10% chance of obese children
Influence of genetics has been born out in twin and adoption studies
A person does not inherit obesity, but a higher risk (tendency) for obesity
5% of people with morbid obesity (BMI ≥40) have a single gene defect to account for their obesity |
|
|
Term
|
Definition
Monozygotic (MZ) = identical
Dizygotic (DZ) = non-identical, “fraternal”
If obesity is genetic, monozygotic twins are much more likely to share similar weights than dizygotic twins
Results show a strong genetic component, especially for those more obese
Results show even when reared apart, results indicate that about 70% of phenotypic variation in obesity is explained by genetic factors |
|
|
Term
|
Definition
No clear relation of weight with their adoptive parents
Strong correlation with weights of biological parents, especially mother |
|
|
Term
|
Definition
During growth, adipose cells increase in number until adulthood
Fat cell number increases more rapidly in obese children
Overweight & obese individuals have more fat cells
Fat cells are capable of increasing their size by 20-fold
If you lose weight, fat cells shrink, but they do not decrease in number |
|
|
Term
| Lipoprotein Lipase, Sexual differences, and individuals with genetic predisposition to obesity and LL |
|
Definition
Enzyme that removes fat from circulating lipoproteins and promotes fat storage
Sexual difference in expression
Men have more LL in adipose tissue located above the waist
Females have more LL in adipose tissue located below the waist
Individuals with the genetic predisposition to obesity have more LL on their fat cells than non-obese
Better able to store fat
Evolutionarily those better able to store fat could better survive times of famine |
|
|
Term
|
Definition
Hormone made by adipose cells that suppresses appetite in the hypothalamus
ob/ob mice lack leptin, become obese
Treating mice with leptin causes them to lose weight
Are a few rare human cases where humans lack leptin (next slides)
Most overweight people actually have elevated levels of leptin and have become resistant to its effects (tolerance)
Turns out that hormonal control of obesity in humans is more complex |
|
|
Term
|
Definition
Made by stomach
Stimulates appetite & fat storage
Opposite effects of leptin
Rises before meal, falls quickly after meal
Lean individuals have high levels
Obese have low levels
Ghrelin levels increase as one loses weight
In addition to lower leptin levels
Get hungrier
Why it may be hard to keep weight off |
|
|
Term
|
Definition
Body has its own set point = weight it tries to maintain
Can change during course of lifetime, usually increases with age
If you lose or gain weight, body activates mechanisms to try and return you to your set point
Difficult for obese to lose weight
May be influenced by genes, environment, and other factors
Can lead to Yo-Yo Dieting |
|
|
Term
|
Definition
When diets initially, they often lose a lot of weight rapidly
Eventually, weight loss slows and the person abandons their diet
Gain the weight back, and often end up weighing more than when they started
Try to diet again, but body adjusts
Lose less weight more slowly
Get frustrated and stop their diet
Gain the weight back
Cycle continues |
|
|
Term
|
Definition
Obesity rates have steadily climbed over past 15 years
In 1995, no state had more than 20% of individuals obese
By 2006, only 6 states under 20%
By 2008, only one state (Colorado) under 20%
17 states = 20-24% obese
26 states = 25-29% obese
6 states ≥ 30% obese
Now 68% of population overweight or obese
More than 33% obese
Genetics of population has NOT significantly changed, so influence must be environmental |
|
|
Term
|
Definition
Availability of delectable foods
Fat is very palatable
Provides taste and scent in foods
Twice the calories per gram as carbs or proteins
Preferentially, and very efficiently, stored in body
Least efficient at signaling satiety
Fast food available everywhere
Every street, malls, gas stations
Inexpensive
Extraordinarily large portion sizes
See as good value too many Calories |
|
|
Term
|
Definition
Hunger is a natural physiological response to need for energy (programmed by heredity)
Appetite is a learned psychological response
We can overreact or underreact to our hunger
Eating is connected to emotions
Yearnings, cravings, addictions affect people
People eat to relieve boredom, nervousness, depression, anxiety
Eating disorders are psychological disorders |
|
|
Term
|
Definition
Can’t forget obesity not only results from increased energy consumption, but also decreased output
Even though some obese people eat less than lean people, they are very inactive
Can’t decrease their food intake less nutritional deficiency
More than 1/3 of overweight people report getting NO physical activity in leisure time
As people put on more weight, they have less desire to move around
May be especially important factor in childhood obesity |
|
|
Term
| Health Risk = Obesity is a disease |
|
Definition
Syndrome X (Metabolic Syndrome)
Insulin resistance, hypertension, hyperlipidemia, CHD
If one has lifelong obesity, they are twice as likely to die prematurely
Degree and length of heaviness may increase chances
But many live long and healthy lives, so susceptibility may also be genetic |
|
|
Term
| Obesity increases the risk of |
|
Definition
Type II Diabetes
Too much fat in muscle can lead to “Glucose Gridlock” (insulin-resistance)
Need more insulin to drive sugar into muscle
Hypertension
Hyperlipidemia
Cardiovascular Disease
Sleep Apnea
Osteoarthritis
Liver Malfunctions
Stroke
Abdominal Hernias
Some Cancers
Varicose Veins
Gout
Gall Bladder Disease
Respiratory Problems
Complications during pregnancy & surgery
Flat Feet |
|
|
Term
|
Definition
Weight gain is around abdomen,
Increases risk of diabetes, stroke, hypertension and coronary heart disease
Increases chance of death
Harder to lose
Not close to active muscle groups
Intra-abdominal fat, when mobilized, easily goes to liver raises LDL
More common in men & smokers
Alcohol (esp. beer) consumption
Can be prevented by physical activity |
|
|
Term
| Inappropriate treatments of obesity OTC |
|
Definition
A) Over-the-Counter (OTC) Weight Loss Supplements & Drugs
Spend up to $2 billion/year on these
Especially young obese women
Make all kind of claims: “blocks carbs”, “eat all you want and lose weight”, but all designed for profit
“Supplements” do NOT need to provide scientific evidence to support their health claims, as drugs do
Many of these products contain amphetamines as appetite suppressants
Could be dangerous and even addictive
In 2000 FDA asked manufacturers to discontinue products with phenylpropanolamine
Appetite suppressant
Can cause rapid & irregular heartbeats, hypertension, kidney failure, strokes, dependency |
|
|
Term
| Inappropriate Treatments: Herbal Products and Dietary Supplements |
|
Definition
Few have proved effective
Many herbs can contain toxins (example - hemlock)
Since marketed as dietary “supplements”, manufactures do not need to provide scientific evidence of their safety or effectiveness
Example) Ephedra (ma huang)
Ma huang was marketed for weight loss
Caused cardiac arrest, abnormal heartbeats, hypertension, strokes, seizures deaths
Active ingredient = ephedrine
Banned by US FDA & Canada
Even decongestants containing pseudoephedrine are also no longer available |
|
|
Term
| Inapprop Treatments: Herbal Laxatives |
|
Definition
Includes senna, aloe, rhubarb root, cascara, caster oil, buckthorn
“Dieter’s tea”
Can cause nausea, vomiting, diarrhea, cramping, fainting
Dieters think laxatives will decrease nutrient absorption and calorie intake
Not true
Nutrients are absorbed in upper small intestine, laxatives work on lower small intestine
Nutrients would have already been absorbed |
|
|
Term
| Inapprop Treatments: Diuretic Abuse |
|
Definition
Lose H2O, not fat
Can result in dehydration & electrolyte imbalance |
|
|
Term
| Inapprop Treatments: FAD Diets |
|
Definition
Sometimes work for a while, but usually success is short-lived
No one requires claims to be verified, no credible research conducted
Can search for data and information after being questioned (backwards)
Often distort bits of legitimate research
How could scientists studying obesity for decades have missed such “obvious” diet connections |
|
|
Term
|
Definition
Most popular fad diets use lower carb intake
Most also include high protein intake
Already talked in Chapter 2 about dangers of low carb, high protein diets
Some place emphasis on “bad” over “good” carbs
“Bad” Carbs = sugar, white flour, potatoes
Rapid rise in sugar
Rapid increase in insulin
Insulin can go so high, it can cause low blood sugar, making one hungry
“Good” Carbs = whole grains, veggies, beans
Moderate, slow rise in blood sugar less hungry |
|
|
Term
|
Definition
a) Books fool you into thinking foods have a set index
Varies in particular food based on how food is cooked, time of day food eaten, what other foods eaten with it, presence or absence of type 1 or 2 diabetes in person eating it
b) All whole grains do not have low GI, all refined grains do not have high GI
c) No clear evidence that higher blood insulin concentration enhances food intake or weight gain in healthy people
d) Evidence that foods with low glycemic index promote weight loss is lacking, need long-term study |
|
|
Term
| Aggressive Treatments: Obesity Drugs |
|
Definition
designed to help one lose ~10% of body weight
Must be used long term
Weight can be regained when stop
Long term use may pose risks
The challenge is to develop treatments that are safe in long term (no side effects)
No such medication currently exists |
|
|
Term
| Obesity Drugs: Sibutramine (Meridia) |
|
Definition
Appetite suppressant; works on neurotransmitters in brain; enhances satiety & elevates energy expenditure
Most effective when combined with a reduced-Calorie diet & increased physical activity
Side effects: dry mouth, rapid heart rate, insomnia, headache, high blood pressure (blood pressure should be carefully monitored) |
|
|
Term
| Obesity Drugs: Orlistat (Xenical) |
|
Definition
Reduces fat digestion & absorption by inhibiting fat-digesting lipases in the GI tract
Reduces fat absorption by 30%
Fat leaves digestive tract intact, carrying fat-soluble vitamins & phytochemicals that would have been absorbed by the body
Possible side effects: similar to those of the artificial fat olestra— diarrhea & digestive distress
Available OTC as Alli™ |
|
|
Term
| Aggressive Treatments: Very Low cal Diets |
|
Definition
800 Cal/day
Must have at least l g high quality protein / kg weight
Little or no fat
Must have a minimum 50 g carbs (enough to spare protein)
Must take vitamin & mineral supplements
Limited number of foods (lean meat, fish, poultry and powdered formula)
However, body acts as if starving
Change in [hormones], metabolism, fluid balance
Therefore, only good for short term
Can develop headache, dry skin, fatigue, nausea
Rarely achieve lasting weight loss
Can be dangerous
Not recommended |
|
|
Term
| Agressive Treatments: Gastric Bypass |
|
Definition
Reduce size of stomach
Restrict pyloric sphincter
Limit food intake
Reduce ghrelin production
Long term safety depends on compliance with diet
Long term = vitamin and mineral deficiencies, psychological problems
Need life-long supervision |
|
|
Term
|
Definition
Only two incisions (laparoscopic)
Safer, faster healing
Lose 50% of excess body weight
Improve blood lipids, diabetes, sleep apnea, hypertension |
|
|
Term
| Reasonable Strategies for weight loss |
|
Definition
Loss of 10-15 lbs can decrease BMI by 2 units
Dramatic decrease in health risks
1 lb. fat = 3,500 kcal
Want to lose 1 lb/week must cut 500 Cal/day
Better not to strive for ideal health in weight, but try for health advances |
|
|
Term
| Reasonable Strategies: Diet |
|
Definition
Energy Intake – need at least 10 Cal/pound of current weight/day to lose fat while returning muscle
Should consume no fewer then 1200 Cal/day
Want small deficit slow loss (1-2 lbs/week)
Or else could face starvation
2) Nutritional Adequacy – at nutritionally dense foods
3) Eat smaller portions of food, but maintain balanced diet
4) Plants - grains, legumes, fruits, veggies should be basis of diet
Low fat, no cholesterol, high fiber, lower Calorie
5) Low fat foods
6) Limit Sugar & Alcohol - Calories (4 & 7 respectively)
7) Plenty of Water (8 or more glasses/day)
Fills stomach feel fuller
Replaces water from food |
|
|
Term
| Reasonable Strategies: Physical Activity: weight Cycling |
|
Definition
Weight Cycling – can occur in diets without physical activity
“Yo-Yo” effect
Repeated cycles of weight loss & regain
Affects body metabolism
Rebound to higher weight & higher body fat
Dangers of weight cycling - increased risk of chronic disease and premature death |
|
|
Term
| Reasonable Strategies: Physical Activity |
|
Definition
2) Increases energy expenditure (burn more Calories)
3) Increase in BMR – both short and long term (if continued)
4) Appetite Control – Body responds to energy expenditure
Mobilizes glucose and fatty acids
Don’t feel hungry
5) Psychological Benefits - decreases stress
Decreases stress eating
Increases self esteem
6) Choosing Activities - more likely to do energy-consuming activities rather than sedentary |
|
|
Term
| Reasonable Strategies: Behavior Modification |
|
Definition
Change behavior by changing environmental cues
Identify triggers that may lead to overeating
Prevent and change behaviors that lead to overeating or underactivity
Establish consequences (penalties or rewards)
Do NOT make rewards food
When you reach goal, don’t “celebrate” and return to old patterns |
|
|
Term
|
Definition
BMI <18.5
≥10% below suggested weight for a given height
Only affects ~10% of Americans
Fewer health risks than obesity unless its severe
Underweight women:
Increased risk of osteoporosis
Become infertile
Give birth to unhealthy babies
If underweight is accompanied by undernutrition more dangerous |
|
|
Term
|
Definition
A) Physical Activity - eat enough Calories and protein to gain muscle
Weight-bearing exercise
B) Energy Dense Foods - high calorie, high fat
Opposite of wt. Loss
Still needs to be nutritionally adequate
C) At least 3 meals/day
D) Larger portions
Person should expect to feel overly full
E) Snack between meals
F) Drink juice or milk instead of H2O |
|
|
Term
| Eating Disorder Statistics |
|
Definition
, 0.5-3.7% of women suffer from anorexia sometime during their life
1.1-4.2% of women suffer from bulimia sometime during life
Estimated roughly 2 million in US with anorexia or bulimia
More common in women than men
5-15% of anorexics or bulimics are men |
|
|
Term
|
Definition
| personality, society and media,family, |
|
|
Term
|
Definition
When low body weight becomes goal, start to view normal body weight as too heavy
Unhealthy dieting (starving, etc.) leads to binging, eating disorders
See “pencil thin” model want to be like her
Many models have eating disorders
Many pictures are airbrushed and enhanced
94% of female students want to lose weight
About 2/3 of girls are unhappy with their weight (1/3 of boys) |
|
|
Term
| Family and Eating Disorder |
|
Definition
1) Mothers always on diet
Concerned with appearance
2) How family relates to food
3) Bad marriages guilt
4) Lack of attention
Want to get attention for how they look
5) Lack of communication
6) Addictions (alcohol and drugs) in family
7) Multi-generational
Learned from previous generation, then passed on
7-12X higher risk if family member
Twin studies
8) Abuse - emotional, mental, physical, sexual
Decreases self worth |
|
|
Term
|
Definition
Most at risk = 14-18 years old
Starve themselves to lost weight
Distorted Body Image - even though very thin, see themselves as fat
Secretive, avoid formal functions with food
Clinical criteria for diagnosis (next slide)
Resembles an addiction behavior is obsessive and compulsive |
|
|
Term
|
Definition
Damage to body due to starvation
Growth ceases
Development falters
Lowered BMR
Heart weakens
Pumps insufficiently & irregularly
Low blood pressure
Loss of brain tissue
Impaired immune response
Anemia
Loss digestive function worsening malnutrition
Death typically to multiple organ failure (heart, kidneys, liver) |
|
|
Term
|
Definition
Deal with two sets behaviors:
1) Those relating to food
2) Relationships involving oneself & others
Team approach = physicians, nurses, psychiatrists, & dieticians
Must tailor appropriate diet to individual’s needs
Rarely are they willing to eat for themselves
Low Risk = family counseling
Cognitive therapy (changing undesirable behaviors by treating, underlying thought processes that contribute)
Behavior modification
Nutritional guidance
High Risk = hospitalization
May need to be force fed by tube |
|
|
Term
| Statistic of treatments of anorexia |
|
Definition
½ of those treated can maintain body weight within 15% of normal
Other ½ have poor to fair outcomes
2/3 of these relapse
1,000 women die each year from anorexia
Either due to cardiac complications or suicide |
|
|
Term
|
Definition
Most at risk = 20-25 years old
More common than anorexia
More men suffer from bulimia than anorexia
Still much more common in women
Secretive nature makes it hard to identify |
|
|
Term
|
Definition
Cathartic drugs - strong laxatives
Emetic drugs – induce vomiting
Abuse diuretics
Leads to fluid & electrolyte metabolic alkalosis
Apathy, confusion, muscle spasms
Vomiting can cause irritation of esophagus & pharynx
Vomiting can also cause erosion of teeth and dental caries
Stomach or esophagus may rupture or tear
Potassium deficiency leads to heart failure |
|
|
Term
|
Definition
Team approach
Easier to treat than anorexia
Most know their behavior is abnormal
More willing to cooperate
Goals = gain control, establish regular eating patterns, restore nutritional health
Eat quantity of nutritious foods to satisfy hunger (at least 1,600 Cal)
Regular exercise
Anorexics can, later in life, become bulimic (50%) |
|
|
Term
|
Definition
Up to half of all people who restrict eating to lose weight periodically binge without purging
About 1/3 of obese people regularly engage in binge eating |
|
|
Term
|
Definition
Similarities = feel out of control
Disgusted, depressed, embarrassed
Guilty or distressed because of their self-preserved gluttony
Differences
People with BED: Consume less during binge
Rarely purge
Exert less restraint during times of dieting
BED responds better to treatment than other eating disorders |
|
|
Term
| Female Athlete triad risks |
|
Definition
1) Young age (adolescence)
2) Pressure to excel at chosen activity
3) Focus on achieving or maintaining “ideal” body weight or body fat %
4) Participation in sports or competitions that judge on aesthetic appeal (gymnasts, figure skating, dance)
5) Dieting at an early age
6) Unsupervised dieting |
|
|
