Transcript Obesity and Your Daily Life

School of Medicine, Health Sciences and Engineering
Susquehanna Township High School
Lecture Series  Week 1, August 2014
Clinical Relevance of This Week’s Topic
Obesity and Your Daily Life
Wen Jie Zhang, MD, PhD
Professor of Pathology
Screening for Cervical Cancer in China
Teaching and Learning Strategy
Scientific Research Reports/Articles
Introduction/Background
• Identifying a disease to study
– Diagnosis, Treatment, Prevention, etc.
Materials and Methods
• Mice/Patients, Reagents/Device/Tests
Results
• Measurements obtained and analyzed
Discussion (and Conclusion)
• The results’ meaning, significance, and conclusion(s)
References/Further Readings
Learning Objectives
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What is obesity
Consequences of obesity
How to measure obesity
How to classify obesity
Obesity control and prevention
Session 1
Introduction
Obesity – An Individual’s Challenge
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Daily news in public media
Intense scientific reports
Commercial Ads on fat reduction
An Individual’s questions:
– Am I overweight or obese?
– What to eat/drink and what not to?
– Should I be on diet?
– How should I exercise to reduce weight?
– Should I consult a doctor for advice?
Which one is
your favorite?
More, please!
Should I do it ?
The World’s Largest McDonald’s
Built on April 23, 1992
Beijing China (~Tiananmen Sq)
29 cash registers
700 seats
40,000 customers/1st Buz day
Buddy, Do I have a piece?
Definition of Obesity
• A medical condition in which excess body fat
has accumulated to the extent that it may
have an adverse effect on health, leading to
reduced life expectancy and/or increased
health risks.
• Body Mass Index (BMI) is a simple index of
weight-for-height that is commonly used to
measure/classify underweight, overweight
and obesity in adults.
Body Mass Index (BMI)
• BMI is defined as the weight in kilograms
divided by the square of the height in meters
(unit=kg/m2).
– Formula: BMI = mass (kg) ÷ height (m)2 = kg/m2
– Example: BMI = 68.2 kg ÷ (1.7m)2
= 68.2÷ 2.89 = 23.6 kg/m2
Table 1: The International Classification of adult underweight,
overweight and obesity according to BMI
Classification
Underweight
Severe thinness
Moderate thinness
Mild thinness
Normal range
Overweight
Pre-obese
Obese
Obese class I
Obese class II
Obese class III
BMI (kg/m2)
Principal cut-off
Additional cut-off
points
points
<18.50
<18.50
<16.00
<16.00
16.00 - 16.99
16.00 - 16.99
17.00 - 18.49
17.00 - 18.49
18.50 - 22.99
18.50 - 24.99
23.00 - 24.99
≥25.00
≥25.00
25.00 - 27.49
25.00 - 29.99
27.50 - 29.99
≥30.00
≥30.00
30.00 - 32.49
30.00 - 34.99
32.50 - 34.99
35.00 - 37.49
35.00 - 39.99
37.50 - 39.99
≥40.00
≥40.00
Source: Adapted from WHO, 1995, WHO, 2000 and WHO 2004.
“Globesity” – Obesity, A Global Issue
On a worldwide scale
• Nutrition improvements and excessive high
energy food
• Lifestyle shift (less active)
• Global pandemic trends
Source: WHO, Global Database on Body Mass Index
Characteristics of BMI
• Age-independent
• Same for both sexes (females may have 1.0
kg/m2 higher than females)
• Population differences
– May not correspond to the same degree of fatness
– BMI-associated health risks may differ
• Caucasians vs. Blacks vs. Asians
Obesity Pandemic Around the Globe 1
Percent of Adults with BMI 18.5-24.99
Source: WHO, Global Database on Body Mass Index
Obesity Pandemic Around the Globe 2
Percent of Adults with BMI ≥30
Source: WHO, Global Database on Body Mass Index
Super Obesity
A "super obese" male with a BMI of 47 kg/m2:
weight 146 kg (322 lb), height 177 cm (5 ft 10 in)
Super Obesity
Hands-on Laboratory Work
Session 2
Materials/Subjects and Methods
Session 3
Results/Observations
Results – Observed
• BMI = 18.5-24.99
• BMI = 25-29.99
• BMI ≥ 30
xx persons, %
xx persons, %
xx persons, %
Session 4
Discussion/Conclusion(s)
% Body Fat
Correlation between BMI and Body Fat
BMI
3 Major Risk Factors of Obesity
• Excessive food energy intake
• Lack of physical activity
• Genetic susceptibility
– 58 genetic loci associated with obesity traits
identified
– >18 BMI-associated loci shared by European and
East Asian ancestry populations
– FTO (Fat Mass and Obesity Associated) gene
– Leptin (adipo-cytokine) gene
Consequences of Obesity
• Increased mortality
• Increased health risks
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Hypertension, coronary heart disease, stroke
Type 2 diabetes
Dyslipidemia
Sleep apnea and respiratory problems
Gallbladder disease
Osteoarthritis
Cancers (10 common cancers including colon, breast,
endometrial) (2014 “Lancet” journal report)
Treatment of Obesity
• Bariatric (fat reduction) surgery
– Most effective
– Long-term weight loss
– Decreased overall mortality
• Medications
– Modest weight loss (2.9 kg [6.4 lb]) in 1 to 4 years
– Side effects concerns
• Gene therapy?
Prevention of Obesity
• Dietary change
Lower food energy diet (long-term or permanent)
Limit weight gain more than weight loss
• Physical exercise
Long-term or permanent
Limit weight gain more than weight loss
Session 5
References/Literature
(Further Readings)
References/Further Readings
• The Obesity Society
– http://www.obesity.org/
• World Health organization (WHO) Global
Database on Body Mass Index
http://apps.who.int/bmi/index.jsp
• The Scientific American (journal)
– Popkin BM. Sci Am, 2007 Sep;297(3):88-95
Key Words Learned
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Obesity
Body Mass Index (BMI)
Epidemic / Pandemic
Genetic susceptibility
Life expectancy
Bariatric surgery
Dietary change
Physical activity
Your Private Project
• Based on what you have learned, figure out your
daily food consumption and make yourself a plan
for healthy diet and physical activities.
• Measure your BMI on a fortnightly or monthly
basis to monitor your body weight.
• Serve as a “physician” for your family members
and monitor their BMI monthly
The End