open energy balance part2 Flashcards
Calories consumed through eating and drinking
Energy In
– provides moisture to allow taste buds to function
– contain enzymes that digest starch
salivary glands
food lubricated by saliva, formed into soft lump/swallowed and passes thru the pharynx and esophagus to stomach
bolus
____ is rhythmic contraction and relaxation of
the circular muscles of the digestive system that
propels the food through
peristalsis
Bolus enters stomach
– Stomach secretes the enzyme pepsin that starts protein digestion
– Little absorption of nutrients occurs in the stomach(Only alcohol, aspirin, & fat-soluble drugs are absorbed)
– Major function is to mix food particles with gastric juices to prepare for absorption in the small intestine (duodenum)
Digestive Process
secreted by the pancreas into the
duodenum to decrease acidity and help in digesting carbohydrates and fats
– Pancreas produces insulin facilitating entry of glucose into bodily
tissues
pancreatic juices
primarily in small intestine (duodenum) • Starch finished from saliva • Proteins finished from stomach • Carbohydrates and fat • 90% of water (allows absorption of vitamins & electrolytes)
absorption of food
____produces bile salts that are stored in the gall bladder and are released into the duodenum to break down fats that are further broken down by pancreatic enzymes
liver
Peristalsis propels food mixture from duodenum to the large intestine(colon)
- peristalsis is more sluggish and irregular in colon
- bacteria inhabit the colon and produce vitamins
typically absorbs only water, a few minerals, and the vitamins proudced by its bacteria
(feces left over after digestion)peristalsis carries feces thru colon, rectum, and then anus when
eliminated
– Stomach flu (norovirus - 50% of all gastroenteritis around the world )
– Inflammation of lining of stomach & small intestine
– Vomiting, diarrhea, abdominal cramps, & nausea
– Excessive food or water, contaminated food or water, or food
poisoning
gastroenteritis
– Watery & frequent BMs
– Lining of intestines can’t properly absorb water & food
– Chronic may result in serious fluid & electrolyte disturbances
diarrhea
– Like diarrhea except mucus, pus, & blood are also excreted
– Protozoan attacks large intestine or a bacterial organism
– Common cause of death in less developed countries
dysentery
• Open sore in the stomach or duodenum lining
• Cause
– Hypersecretion of hydrochloric acid
– Pepsin (enzyme) digests part of the lining
– H. pylori bacterium contributes to development
– Stress aggravates ulcers but is not necessary
Peptic Ulcer
• 20% of the US population has weekly reflux
• Muscle between the esophagus and the
stomach does not work properly
• Stomach acid flows back up and irritates the
esophagus
• This backward flow is reflux or heartburn
Gastroesophageal Reflux Disease
GERD
• Cholecystis
– Infection & inflammation of gallbladder
• Gallstones – Made up of cholesterol, calcium, bile, & inorganic salts – Move into duct of gallbladder – Cause painful spasms
Gallbladder
• Bacterial infection in appendix caused by
obstruction due to wastes and bacteria
• Pain, increased peristalsis, nausea
• If appendix ruptures, bacteria are released into
abdomen or peritoneum & further infection &
death can occur
Appendicitis
Viral inflammation & damage to liver=
hepatitis
– Contagious & serious
– Transmitted thru food & water
– Bilirubin can’t pass thru ducts & collects in blood (jaundice)
– Fatigue, fever, pain, nausea, vomiting, & diarrhea
heptatitis A
– Similar to Hep A but more serious
– Spread by blood, needles, sexual contact, mother-to-infant
hepatitis B
– Spread by blood & needles
hepatitis C
– IV drug users
– Must have Hep B infection first
hepatitis D
– Like Hep A but caused by different virus
hepatitis E
– Protein hormone secreted by fat (adipose) cells
– Signals hypothalamus about stores of fat
– Inhibits neurons that stimulate appetite
– Activates neurons that suppress appetite
Leptin
– Hormone produced by beta cells in the pancreas
– Allows body cells to take in glucose for their use
– High insulin leads to intake of more glucose than the cells can use and the excess is converted into fat
– Therefore, the higher the insulin levels, the more fat
– Receptors in the hypothalamus detect insulin levels
Insulin
– Peptide hormone secreted by cells in the stomach
– Spikes just before meals, drops afterwards
– When given ghrelin injections, people feel extremely hungry
– Acts in the hypothalamus to activate production of other neurochemicals
involved in the regulation of eating, such as neuropeptide Y (that stimulates Agouti-related peptide) and the orexins
– Melanin-concentrating hormone is another brain peptide that increases
food intake and interacts with ghrelin
Ghrelin
– Peptide hormone produced by intestines
– Acts on the brain and produces feelings of satiation
– Short-term use is to tell us to stop eating
– Other peptide hormones produced by the intestines to produce satiation are glucagon-like peptide 1 and peptide Y
Cholecystokinin (CCK)
– Large role in controlling eating
– Ventromedial hypothalamus
• When damaged, rats eat excessively
• May play a role in some cases of human obesity
hypothalamus
excessive body fat
– Women: fat should be 20% to 27% of body tissue
– Men: fat should be 15% to 22% of body tissue
Obesity
Create tables of weight based on height, frame
size, and mortality rates (Met Life)
• Calculate an index of weight and height (BMI)
– Body Mass Index (BMI) = kg/m2
– Overweight = 25-29.9
– Obese ≥ 30
• Determine percentage and distribution of body fat
– Imaging (computer tomography, ultrasound, magnetic
resonance imaging, and PET scanning)
– Skinfold test
– Bioelectrical impedance measurement
• Fat distribution as ratio of waist to hip size
– Particular risk to “apples” rather than “pears” (fat
localized in abdomen)
• More psychologically reactive to stress
• Greater cardiovascular reactivity
• Risk factor for metabolic syndrome
How we measure obesity
Americans are fattest in the world
• 33% obese
• Another 34% overweight
Epidemic stems from – Genetic susceptibility – Increasing availability of high-fat, high-energy foods – Increased portions – Low levels of physical activity
Prevalence of overweight children in the past 20 years – Doubled among those 6 to 11 years – Tripled among those 12 to 17 years – Rates • 17% overweight • 31% at risk
80% of all people who were overweight as
children go on to be overweight as adults
– Relationship is due to genetic and dietary factors
– Number of fat cells determined early in life by genetic
factors or early eating habits
– Metabolic rate
– Still rates vary
family hisotry and obesity
– Voluntary or disordered sleeping – Leads to insulin resistance causing increased glucose and insulin levels – Decreases leptin levels – Increases ghrelin levels
risk factor for obesity:sleep
– High basal insulin levels prompt overeating due to increased hunger – Obese have larger fat cells – Cycles of dieting lower metabolic rate • Yo-Yo dieting • Loss and regain affects abdominal fat
obesity and dieting as risk factors [obesity risk factor for obesity]
1 kilogram = 2.20462262 pounds
Definition of Weight Cycling
– Cooper Clinic: ≥5 episodes of weight loss of ≥2.3 kg/episode
– Each person has ideal biological weight
– Deviations from setpoint are achieved with difficulty
– Leptin signals the hypothalamus to regulate eating
– Genetics may determine setpoint
Setpoint Theory
– Positive reinforcers of eating control weight
– Learn to regulate eating based on
• Biological factors (time since eating; blood glucose)
• Personal pleasure (taste & pleasure)
• Social context (culture & social setting)
• Evolutionary factors (adaptive to eat when food is present)
– Variety in food selection increases eating
– Advertising promotes desirability
– Diets high in fat and sugar may disrupt satiation signals and increase appetite
positive incentive model
• Chief cause of disability
– number of people aged 30-49 who cannot care for
themselves has jumped by 50%
Problems with health care
– May not fit in standard wheelchairs
– X-rays may not penetrate far enough
– Blood pressure cuffs may not fit
A U-shaped relationship exists between weight and poor
health
Greatest risk for poor health occurs with obesity and
especially morbid obesity
– All-cause mortality (especially due to CVD)
– Increased use of health care
– Development of diseases such as Type 2 diabetes, high blood
pressure, CVD, gallbladder disease, migraine headache, kidney
stones, sleep apnea, respiratory problems, liver disease,
osteoarthritis, reproductive problems in women, colon cancer
obesity is risk factor
– Normal BMI but an accumulation of fat in the
belly and around internal organs
– Causes low-level inflammation that gradually
damages tissue and blood vessels
Normal weight obesity (NWO)
– BMI overweight
– Body-fat percentage is lower than 30% (20% for
men) and blood chemistry is normal
– Many athletes are in this category.
– Continue to eat smart and exercise, but not
unhealthy
Fat and Fit:
– Emphasizes fruits, vegetables, whole grains, and fatfree or low-fat milk and milk products;
– Includes lean meats, poultry, fish, beans, eggs, and nuts; and
– Is low in saturated fats, trans fats, cholesterol, salt (sodium), and added sugars.
What is a “Healthy Diet”?
Stress has a direct effect on eating
– Especially true for adolescents
Greater stress tied to – Eating more fatty foods – Eating less fruit and vegetables – Skipping breakfast – More between-meals snacks
• 50% eat more when under stress
– Women more likely to eat more under stress
– Stress removes self-control in dieters/obese
– Choose foods containing more water, “chewier”
– Choose salty, low calorie foods
– Negative emotions – sweet, high-fat foods
• 50% eat less when under stress
– Men, compared to women, eat less under stress
– Non-dieting, non-obese suppress hunger cues
Weight Control:
Stress and Eating
Obese individuals attempt to lose weight because
– It is considered unattractive (a primary reason)
– It carries a social stigma (a primary reason)
– They perceive that it is a health risk
– It is coupled with psychological distress
- Reduce portion size
- Restrict types of food
- Increase exercise
- Rely on drastic medical procedures
- Use a combination of these approaches
Approaches to Losing Weight
– Eliminate certain foods
• Low-carbohydrate (Atkins, South Beach, Zone, Sugarbusters)
– Potentially unhealthy
– 50% dropout
• High-carbohydrate (complex) and low-fat (Ornish, Mediterranean)
– Often vegetarian or modified vegetarian
– Easy, can eat more food because complex carbs have fewer
calories than fat
– Lose weight but dropout is high (crave fatty foods)
– Only eat certain foods
• Monotony leads to decreased caloric intake
• Very unhealthy!
• Liquid diets may be nutritionally better but still monotonous and lack
fiber
diet:Restrict types of food
– Variety of foods with smaller portions
– Reasonable and healthy
– Best combination of weight loss and low dropout rate
– Example: Weight Watchers
Reduce portion size
– Small losses, rarely maintained for long
– Many are bad nutritional choices
– Risk of yo-yo dieting to CHD > risk of obesity alone
Dieting
– Dangerous – start losing muscle and organ tissue
– Protein-sparing modified fast (high protein in limited amounts)
– Usually employed with other techniques
Fasting
– Stomach stapled or banded to reduce capacity
– Gastric bypass
– Drastic weight loss
surgery
– Behavior modification is used to change lifestyle with
emphasis on eating right and exercise (vs. weight loss)
– Screening, self-monitoring, control over eating, exercise
– Controlling self-talk, social support, relapse prevention
The multimodal approach
• Efforts are somewhat successful
– Losing 2 pounds/ week for 20 weeks
– Maintenance for 2 years
– Programs emphasize self-direction, exercise, and relapse prevention
Evaluation of Cognitive-Behavioral
Techniques
• Health psychologists suggest
– Sensible eating and exercise
– Rather than specific weight reduction techniques
Public Health Approach for prevention with fam at risk training involves…
sensible meal planning and helping children develop healthy eating habits
public health approach of behavioral treatment
adult obesity is diff to modify and childhood obesity is impressive succeses[reinforcement for exericse is effective and reduced tv]
– Women at menopause: exercise and good eating
habits may prevent the weight gain that is very
common
– Special “junk food tax” on foods high in sugars and fats
– Restriction of advertising to children
– Health warnings regarding foods high in sugars and
fats
weight gain prevention
– In response to specific health risk
– Education and self-monitoring are key
– Cognitive-behavioral interventions
Individual interventions to modify diet
- Precontemplation
- Contemplation
- Preparation
- Action
- Maintenance
Transtheoretical Model of Change - Different
interventions are required for each stage
– Easier for target member to change when other family
members change also
– Wives usually shop and prepare food
– Husband’s food preferences likely to determine what the
family actually eats
Family interventions/meet with dietary counselor
– Initial success rates, but not impressive long term
change
– More effective – intervention directed toward particular
at-risk groups (Hispanic dietary study)
– Social engineering possibilities
• Banning snack foods from schools
• Making snack foods expensive; healthy foods less
Community interventions
• Dissatisfaction with body
• Focus on body as a way to change dissatisfaction
• Preoccupation with food
• Negative family interactions
• Childhood sexual abuse
• Low self-esteem
• High levels of anxiety, depression, & negative mood
• Genetic or neuroendocrine predisposition (e.g.,
serotonin)
Risk Factors for Eating Disorders
• An eating disorder amounting to self-starvation
• Dieting and exercising until body weight is grossly below
optimum level
–
Eating Disorders:
Anorexia Nervosa
restricting type:eat almost nothing and lose lbs by dieting, fasting,exercising or combo/ bingepurge type:eat large quantities of food and then use vomit or laxatives
subtypes of anorexia nervosa
• Physiological
– Amenorrhea, abnormal levels of neuroactive steroids, Turner’s syndrome, hypothalamic abnormalities, chronically overreact to stress
• Profiles show
– Depression, anxiety, low self-esteem, poor sense of
mastery
• Genetic contributions
• Family interaction patterns – lack of control, needfor approval
Factors in Developing Anorexia
Nervosa
• Highest mortality rate of any psychiatric disorder • 5-10% die of disorder – Most suffer cardiac arrhythmia – Suicide is also a problem • Recovery rates: – 50% recover – 30% improve but still struggle – 20% continue
Health Consequences of Anorexia
Nervosa
• Initiation of treatment is hard because of distorted body image
• First treatment step: stabilize medical effects of starvation
• Bring weight up to safe level
• Improve healthy eating
• Improve body image
• Use
– Individual and group cognitive behavioral therapy
– Supervised meals
– Meal planning
– Nutrition education
Treatment of Anorexia Nervosa
• An eating syndrome characterized by alternating cycles
of binge eating and purging through such techniques as Vomiting, Laxative abuse,Extreme dieting/fasting,Drug or alcohol abuse,Excessive exercising
• Problem with impulse control
• Not preoccupied with losing weight
• May become bulimic and not anorexic if can’t resist
impulse to eat and yet feels the body dissatisfaction common to both disorders
Bulimia
– Binge phase – out of control
– Purge phase – attempt to regain control
Issues of control with bulimia
• Control of eating shifts from internal sensations to
cognitively based decisions
• Families placing high value on thinness
– produce bulimic daughters
• Childhood sexual abuse, physical abuse, PTSD
• Genetic basis: Bulimia runs in families
-more common than anorexia nervosa
-equally prevalent among various social classes and ethnic groups but restricted to western cultures
bulimia
• Very seldom fatal
• Hypoglycemia (low blood sugar) from intake of large quantities of sweets and overproduction of insulin
– Dizziness, fatigue, depression, cravings for more sugar
• Poor diet/nutrition results in lethargy and depression
• Obsessed with planning the next binge
• Hydrochloric acid from frequent vomiting erodes teeth enamel
• Hydrochloric acid also damages mouth and esophagus
• Anemia
• Electrolyte imbalance
• Alkalosis
• Laxatives & diuretics may cause kidney damage, dehydration, spastic colon, loss of control over bowel movements
Health Consequences of Bulimia
• Cognitive behavioral therapy • Interpersonal psychotherapy • Drugs like the antidepressant Prozac • Combination of drugs and psychotherapy • Psychoeducational interventions aimed at preventing bulimia
Treatment for Bulimia
• Same type of out-of-control eating as in bulimia
but people do not purge
• Not officially a DSM disorder yet
• Risk factor for obesity
• More common among women than among men
• Occurs in all ethnic groups and in Western and
non-Western cultures
• More common than anorexia or bulimia
• Also tend to have behavioral or psychiatric
problems
Binge Eating Disorder
• Cognitive behavioral therapy (CBT) helps to
control binges
• Use another strategy for weight loss
• Prozac doesn’t add to CBT
• Adding a weight loss drug to CBT does help
• orlistat (Xenical; Alli) or sibutramine (Meridia)
Treatment for Binge Eating
chemical gatekeeper, most ancient of the senses, important in selection and rejection of foods
taste
