EXSC 480 Exam 3 Flashcards
How does thermodynamics relate to weight maintenance?
reducing thermodynaic efficiency results in increased weight loss
a calorie isn’t always a calorie (2nd law)
you have to decrease consumption or increase expenditure (1st law)
What are some factors that influece weight loss?
satiety age behaviors body composition food supply diet economics medications genes gut microbiota hormones metabolic rate
Energy density
differences due to fat, water, and fiber content
macronutrients can also hvae differeing effects on satitaion/satiety
Which macronutrient has the greatest effect of satiety?
Protein
Very low calorie diets
Less than 800 kcal
hard to maintain for longer than 6 months
can negatively bone health, possible eating disorders
Results of VLCD
10-40% of weight loss
1.5-2.5 kg lost per week
Low-calorie diets
800-1500 kcals
or can be classified as decreasing 500-750 kcal in obese and 300-500 in overweight
LCD results
improve cholesterol, LDL, triglycerides, HDL
8% body weight loss
can be used after a VLCD
Low fat diet
less than 30% of total kcal comes from fat
weight loss of about 5.41 kg
Very low fat diet
15% from fat
Low fat diet results
4 months to a year 6% to 12% body weight loss
improvement in total cholesterol, LDL. Variable effects on HDL and triglycerides
Fat diets and weight loss
fat energy is dense but has weak satiating effect
low fat diet may induce greater weight loss
helps to reduce total energy intake
heart-healthy approach
Low-fat to low-carb diets
difference is not significant
Low-carb diets
there isn’t a set definition
can range from 10-20% of kcals from carbs
Very low carb diet
less than 10% total kcal from carbs
Why does a low carb diet work?
Increased thermogenic effects of protein intake
Greater protein turnover for gluconeogenesis
Loss of energy through excretion of ketones
Increased satiety, allowing lower energy intake w/out hunger
Specific metabolic advantage
Low carb drawbacks
greater change at 6 months than low fat
but same results at a year (33% vs 34%)
only 59% were able to do a whole year
Two year low carb
HDL cholesterol higher than low calorie diet
but more adverse symptoms than other low diets
Negatives of low carb diet
less fat loss even with more weight loss
lots of adverse side effects
Positives of low carb diet
8-12 kg at 6 months
5 kg at a year
increased energy expenditure
decreased triglycerides, increased HDL
Carb Insulin Model
increased insulin levels and high carb levels don’t lead to oxidation but to fat storage
this causes increased hunger and food cravings, lower energy expendture, weight gain.
Atkins, Zone, Weight Watchers
all achieve modest and similar long-term weight loss
all low carb
Intermittent Fasting
Insulin levels drop w/out snacking
because of low insulin levels, fat cells release energy and are burned
Fasting protocols
fasting every other day
7 AM to 3 PM or 7 Am to 7 PM eating pattern
Mediterranean Diet
eat rarely red meat
eat in moderation poultry, eggs, cheese, yogurt
Mediterranean vs low fat
more effective
at 6 years, MD had lost 3.1 kg vs .06 kg
Glycemic index diet
limit refined grains and sweets
3 meals a day and 1-2 snacks..
Eat slowly and stop when full
Who should do a glycemic index diet?
those with high insulin secretion
beneficial for HDL and not LDL
Problems w/gluten free
expensive
processed foods
fewer nutrients
doesn’t induce weight loss
Low sugar
decrease in .8 kg
doesn’t necessarily help you to lose weight because you intake other carbs
Dieting problems
preoccupation w/food food is the enemy slowed metabolism weight rebound dissatisfaction w/body
Intuitive eating attitudes
body acceptance
dieting is harmful
Intuitive eating behaviors
learn to not eat for emtional, environmental or social reasons
learn to interpret body singals and respond in a positive way
Intuitive eating principles
Reject diet mentality honor your hunger make peace with food challenge food police discover satisfaction feel your fullness cope w/emotions with kindess respect your body love exercise honor you health
Efficacy of intuitive eating
lower BMI more evident w/time less weight cycling improves mental health and mindfulness increases internal cues to eat
Drawbacks of intuitive eating
little evidence for weight reduction
not related to increased PA
influence on healthy diet is mixed
PA for maintaining or improving health
150 min/week
PA for prevention of weight gain
150-250 min/week
PA for clinically significant weight loss
225 to 420 min/week
PA for preventing weight gain after weight loss
200 to 300 min/week
Heterogeneity of weight loss/exercise in research studies
PA is defined and recorded differently
weight loss or benefits of PA can differ from study to study
Clinical trials w/no or modest weight loss still have benefits
glucose control endothelial function lipoportein particle size HDL quality of life CVD risk
Pedometer weight loss
0 to 1 kg, not significant
Aerobic exercise training
0 to 2 kg. only high exercise volumes
Resistance training
no weight loss, effects visceral fat. Increases strength and confidence
Aerobic and resistance
0 to 2 kg. only high exercise volumes
Caloric restriction and aerobic exercise
9 to 13 kg
Randomized groups and PA
majority of studies don’t show a correlation between PA and weight loss
Exercise compliance and PA
most show no idfference between groups of exericse amount.
50% compliance showed best correlation w/weight loss
Only when actual weight loss was recorded…
was there an actual correlation between weight loss and PA
Obesity and Preconception
INFERTILITY lower peak estradiol worse hormone and metabolic profile PCOS risk miscarriages
How much reduction in weight can improve infertility?
5-10%
Obesity and Prenatal
fetal anomalies congenital heart disease insulin resistance preeclampsia diabetes preterm and stillbirth
Gestational Diabetes
increased risk of 17% if obese
risk of developing type 2 later
Preeclampsia
higher risk for obese 2.2 RR and overweight 1.7 RR
Obesity and Birth
hormones distorted
induction is needed
prolonged labor
c-section
Depression and obesity
6-8 weeks postpartum
risk is 7.5 fold greater
How to reduce risk of pregnancy complications
EXERCISE
active a year before = reduction by 60% of issues
PA and preeclampsia
reduces risk by 35% to 70%
PA and pregnancy
150 min/wk of moderate
can begin after giving brith
If you did vigorous activity before, you can continue to be active
pregnancy weight gain for underweight women
28 to 40 lbs
pregnancy weight gain for normal weight
25 to 35 lbs
pregnancy weight gain for overweight women
15 to 25 lbs
pregnancy weight gain for obese women
11 to 20 lbs
Average retention weight after pregnancy
11.8 lbs
Obese and postpartum weight
Those that were obese that gained within or less than recommended maintained postpartum weight below pre-pregnancy weight
underweight for kids
below 5th percentile
normal weight for kids
5th to 85th percentile
overweight for kids
85th to 95th percentile
Obese class 1 for kids
abover 95th percentile
Obese class 2 for kids
greater than 120% of 95th or BMI is greater than 35
Obese class 3 for kids
greater than 140% of 95th or BMI is greater than 40
Prevelance of childhood obesity
1/2 of adult
less than 20%
adiposity rebound
o At age 5-7, children should be at the lowest weight
o If the child begins to gain weight at age 2 or it’s the lowest weight for them, they will be overweight/obese
Intrauterine effects on kid’s weight
Gut microbiome
Genes
Metabolic syndrome, insulin resistance, CVD
Diabetes.
Famine, increased risk to rapid weight gain
Postnatal effects on kid’s weight
Low birth weight –> abdominal obesity
breastfeeding
type of breast milk (formula, real milk, etc)
breastfeeding effects on kids
30-50% reduction in risk for obesity
introducing food before 3 months increases risk by 30%
scheduled feeding doubles risk of rapid infant weight gain
kids 2-14 have a 15% lower risk for being obese
Familial situations on kids weight
PA patterns and eating patterns Preferences for food Degree of parental control over intake Stress Strong familial component
Obesity begins in adolesvence
30% of females
10% of males
How parents can have an positive effect on child’s weight
o Dietary change o Physical activity o Parental involvement o Psychological o Structure of environment, encourage/discourage, not exerting pressure
Psychological things parents can help w/weight
Praise good behaviors
Don’t use food as rewards
Remove temptations
Be a role model and consistent
Interventions that families can do to improve weight
stable meal times
healthy food options
model desired behaviors
When should medication be prescribed for obesity?
greater than 30 BMI
greater than 27 w/comorbities
Orlistat
GI lipase inhibitor
impairs digestion of dietary fat
oily discharge from rectum
don’t use w/birth control, seizure meds, thyroid meds
Orlistat important things
APPROVED for use in kids
3% reduction in weight
Phentermine
sympathomimetic amine
increases satiety
can cause high BP and heart problems
interacts with antidepressants, alcohol
Phentermine important things
Oldest approved drug (not FDA approved)
most commonly prescribed
Lorcaserin
stopped/discontinued due to increased risk for cancer
Ligraglutide
glucagon peptide 1 receptor agonist
lower blood sugar
stimualtes pancreatic function
lose 5-10%
can become hypoglycemic
increased suicide risk and gastric emptying
Naltrexone and Bupropion
lose 5-10% of weight
helps with addiction and depression
should not be used in non-adults
Phentermine and Topiramate
anti obesity and seizures/migraines
5-10% of body weight
birth defects possible w/topir
When should bariatric surgery be suggested?
class 2 and 3 obesity people w/2 or more comorbities
Has the amount of people for bariatric surgery increased or decreased?
increased over the past 20 years
Bariatric surgery is considered a
consistent or sustained weight loss method
Malabsorptive
Duodeno-jejdunal bypass
helps w/type 2 diabetes
avoids issues w/gastric bypass
hyperlipidemia improvement
Restrictive
laparoscopic banding
greatest result w/sleep apnea
constant readjusting needed
doesn’t obtain nearly as much weight loss
Restrictive and Malabsorptive
Roux-en-y gastric bypass
you can’t eat sweet things with it
used to be the most common
stomach pouch = golf ball
drains outside of stomach and duodenum
2 parts: sleeve and switch
Sleeve of bypass
creates sleeve in stomach
part A
very common, most popular. Provides great results
Switch of bypass
not used often but provides the best results
jejunum is attached instead of duodenum
have to stay up on vitamins and supplements
12 years after surgery
27% still have less weight
diabetes, hypertension, and dyslipidemia remain improved
Which ones are the most popular surgeries?
ROUX
SLEEVE
LAP BAND
Which are the most effective surgeries?
- Roux
- Sleeve
- Band
Which surgery is reversible?
Lap band
requires post-surgical adjustments for best results
Given that nutritional deficiencies (i.e. protein malnutrition, vitamin B12, vitamin D, iron, calcium, and folate insufficiencies) are more likely to occur with malabsorptive procedures, which would have a greater need for regular post-surgical vitamin/mineral supplementation?
SWITCH > SLEEVE < RYGB > BAND
Compared to a usual diet in studies that last longer than a year, low fat diets …
produce an average weight loss of ~5 kg.
are thought to be a heart-healthy approach to weight loss.
may not be statistically different from weight loss achieved via low carb diets.
Pains from ED
headaches Chest pain Abdominal pain mental health neuropathic pain m/s pain
Refeeding syndrome
decreased phosphorus
decreased potassium
decreased magnesium
