Obesity - Lecture 19 Flashcards
Main causes of obesity?
Genetics, Social Determinants, Environments
Trends in Obesity in the US
In the 80’s not many people had a BMI over 30 but over the decades almost every state has a prevalence of obesity >25%
What do the trends make of obesity?
Obesity as the new normal.
Trends in Obesity in Canada
- Overtime prevalence in obesity increased
- Quebec had lowest prevalence due to smoking
- 1/3 Canadians Obese
In the rise of obesity does everyone gain same weight over time?
Proportional increase for class 2 & 3 obese
Who is most likely to have a high prevalence of obesity related conditions?
Class 2 and 3; those who’s BMI’s are high
Trends of prevalence in overweight and obesity
Prevalence of overweight is minimal while prevalence of obesity is high
What about third world countries?
Along with obesity, dealing with acute and chronic conditions too. (Starvation)
Relationship between Mortality Risk and BMI
Very Low BMI increases risk and Class 3 Obesity is a very high risk.
Who are the people that fall into obesity
Those who work at home. Staying hidden and out of sight from the rest of the world.
Why is it hard for many to recognize what’s considered obesity?
Based on the environment we live in, obesity may be different to us.
BMI for guys vs. girls
High BMI for guys is accepted societally rather than a high BMI for girls.
BMI Growth Curve?
Graph that plots where kids BMI should be as they age?
What age does the curve slightly drop?
Age 4-5 BMI curve drops.
What is obesity defined as according to the growth curve
A percentile
What percentile is overweight
90-95th percentile (Out of 100 kids); 95+ is obesity
What’s the normal range?
Anything between the 5-90 percentile should be fine.
Is there a cutoff for kids?
Not necessarily as it’s a curve depicting how BMI should look not necessarily any cutoffs
How do parents play a role in their child’s weight?
- Mothers underestimated weight of child
- Mothers who themselves are overweight were more common to underestimate weight of child
Why is it challenging from a medical perspective to talk about obesity with a parent?
It has a negative stigma. Very sensitive to it and makes parents at “fault” for not caring for child’s health.
Trends in Overweight and Obesity 1981-1996
Lot more Boys and Girls transitioned to obesity compared to men & women.
Why is it impossible for the entire world to be obese in the future?
Some are genetically blessed, so metabolism is hardly affected from eating junk.
What are the newer trends of obesity in Canada now?
Prevalence of obesity is starting to slowly decline.
Relationship between Childhood BMI and Adult Metabolic Abnormalities
Risk of chronic disease developing at a young age and that leading to losing limbs as an adult.
Disadvantages of Too much Fat?
- Associated health risks
- Physical movement limited due to weight on you
- Extra stress on bones and joints
- Psychological Damage (society’s bias against overweight)
Does healthcare provide aid?
They act along the lines of society where for example they won’t offer you hip replacement because you are overweight. (Putting blame on those who can’t control it)
Subcutaneous Fat
The fat on the outside (skin) that you can pinch
What do Subcutaneous skinfolds assess?
Subcutaneous fat on the outside not the visceral fat
Visceral Fat
Fat that surrounds your organs
How much percent of fat does Subcutaneous and Visceral Fat make up?
Visceral Fat is about 10-15% for males and 5% for females while the rest is subcutaneous fat
Which fat has more of a health related issue (Subcutaneous or Visceral?)
Visceral fat is more important towards health risk
How is visceral fat contributing to obesity
Small affect on total obesity but a huge impact on obesity related disease
How does Visceral Fat relate to Cardiovascular Risk
High visceral fat is related to Low amounts of HDL (good cholesterol)
Does Liposuction improve health risk brought upon by Visceral Fat
No; study shows that liposuction targeted only subcutaneous fat not visceral fat at all
Why can’t liposuction target visceral fat
Blood flow in visceral fat so puncture can happen and lots of blood loss.
How can we lose our visceral fat then?
Weight loss through exercise and diet
Relationship between weight loss and visceral fat
Weight loss leads to proportional increased loss of visceral fat
How can visceral fat be measured
Anthrpometric measure; loss in visceral fat means change in waist circumference
High BMI + Large Waist Circumference = Increased Health Risk
Interaction of BMI and WC in terms of Health
What is Weight Control thought of as?
A scale where your energy intake and energy expenditure are balanced which leads to no weight change
How can weight control lead to weight gain
Increase in caloric intake and living a sedentary lifestyle
How can weight control lead to weight loss?
Diet and Exercise, Vigorous Training, Dieting
What’s the energy surplus (calories above the amount you’re recommended to eat) that translates to weight gain
15 extra calories per day
What percentile has an energy surplus of 50kcal/day
90th percentile
RMR (Resting Metabolic Rate)
The number of calories you need to burn to stay do basic functions that help you stay alive
How much of your energy expenditure does RMR count for?
60-75% of energy expenditure; calories burned from doing nothing
Where does the rest of your energy expenditure go to?
Non-exercise activities like talking and standing. Also from feeding yourself
Modern conveniences saving energy?
No longer doing things manually which saves you energy; but advancements like these in the workplace has lead to progressive weight gain every year.
How much calories saved leads to a 20% higher chance of death?
Saving 130cal/day
Do genes play a role in obesity?
Based on the monozygotic twins study; they looked awfully similar so this proves that genetics does play a huge factor in developing obesity
How many genetical regions were found to influence obesity traits
> 140
Exposure to things in environment linked to obesity
Plastics, Pesticides, Quitting Smoking
How does exposure to these things in the environment cause a higher risk for obesity
Metabolism goes down, eating habits go up.
Why is eating and exercising as you do now make you gain more weight compared to in the 70’s
Everything mentioned before; how we made ways to save energy and built an environment perfect for weight gain
What did food intake trends in Canada show for Obesity and food intake
Decreased food intake and greater exercise but obesity was higher (are they lying?)
Eating the same amount of calories in the 1970’s vs. 2008 shows?
There’s an increase in BMI with the exact same amount of calories consumed.
Confirmation Bias
Seeking evidence that confirms what we believe and ignoring the facts that contradict that belief.
What is the biggest cause of obesity that is diverse among different individuals
No specific trigger (people being unsure about how it happened); possibly a combination of many things that happened at once.
Old Recommendations for Weight during Pregnancy for BMI less than 20
12.5-18kg
Old Recommended weight for pregnancy of BMI 20-27
11.5-16kg
Old Recommended weight for pregnant person of BMI >27
7.0-11.5
What happened when pregnant mother gained weight?
Child will have risk for obesity; due to calorie intake during preganancy
New Weight gain for Normal weight pregnant people
11.5-16kg
New recommended weight gain for pregnant Overweight BMI
7-11.5kg
New recommended weight gain for obese pregnant people
5-9kg
What’s the main message for gaining weight and calorie intake when pregnant
Must watch your weight gain when pregnant by trying not to eat everything you crave
Advantage of Fat
It’s a good energy store, but too much is unnecessary
Liver Glycogen and Muscle Glycogen calories
Good proportion of calories that you can survive off of for days because the adipose tissue has the most amount of calories
More advantages of fat
- Insulation
- Sport (Swimming and buoyancy)
- Appearance
- Improved survival rates for many chronic diseases
Obesity Paradox
Those with obesity likely to get obesity related conditions but also more likelier to survive than those without obesity when faced with disease
Metabolic reserves and how it explains obesity paradox
Higher amounts of energy in reserves to expend and combat disease, so lean person will run out of resources to combat it.
