Evolution of the Obesity Epidemic
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Transcript Evolution of the Obesity Epidemic
Evolution of the Obesity
Epidemic
Information from Time Magazine, National Geographic
Magazine, and other sources
Exercise and Body Composition
• Two major factors that lead to obesity:
– Over-nutrition – consuming too much
– Under-expenditure – expending too little
energy
Over-nourishment
• Increased caloric consumption
• Increased portion sizes
• Eating as entertainment
Exercise and Body Composition
• Decreased daily energy expenditure
– Transportation
– Manual Labor
– Entertainment
Role of Genetics
• About 2/3rds of tendency for obesity is
genetic
– Factors include
•
•
•
•
Low RMR 15%
High RQ (low fat oxidation) 5%
Low spontaneous physical activity (fidgeting) 10%
Other???
• (Ravuzzin, ACSM, 2008)
Ancient History
• Humans started by living in a world of
scarcity.
• To survive they developed the habit of
eating everything that tasted good
whenever they could find it.
Ancient History
• That's the way it was during 99.9% of
human evolution.
• For most of the 7 million years of human
existence, life has been "nasty, brutish,
and short"
• Thomas Hobbes
Ancient History
• Life expectancy was under 30 years mainly due to accidents, infection,
childbirth, and predation.
Ancient History
• Early diet consisted of fruits, shoots, nuts,
tubers, and vegetation - all low in calories took constant work and eating whatever
we found just to stay alive.
• Fruits were highly desirable so we learned
to seek fructose and glucose.
Evolution
• It was some 2.5 million years ago that our
ancestors developed a taste for meat.
• As a result, the human brain became
markedly bigger and more complex at the
same time.
• We also increased in physical size.
Evolution
• Because it's packed with nutrients and
calories, meat gave early humans a
respite from constant feeding.
• Our ancestors ate a diet composed of lean
meats, vegetables, and fruits and worked
out almost nonstop.
Agriculture
• 150,000 to 100,000 years ago.
• Provided steady source of food.
• No longer hunter/gatherers.
• Farming became major source of food.
Agriculture
• Nutritionally the shift away from wild meat,
fruits and vegetables to a diet of mostly
cultivated grains robbed humans of many
of the essential amino acids.
• Still physical exertion was common.
Progress?
Environment
• Our bodies evolved in an environment
where food was scare and movement was
required
• We now find ourselves in an environment
where food is abundant and movement is
optional – recent development
Then and Now
• In 1700, the average Briton consumed 7.5
pounds of sugar per year.
• In the US, we currently consume 150
pounds of sweetener per year.
Overconsumption
• Adult women are now eating 335 more
calories per day than they did in 1971,
while adult men have upped their intake by
168 calories.
Overconsumption
• We each ate 1775 pounds of food in 2000,
up from 1497 in 1970.
• Although it appears we are eating more
vegetables, almost 1/3 of these vegetables
were iceberg lettuce, French fries, and
potato chips.
Now
• Rapid change in environment last 50 years
compared to previous 50,000 years.
• Removal of physical activity combined with
abundance of food.
Now
Daily imbalance is on average small: an
extra can of soda per day (150 kcal) can
add 15.6 pounds per year
Factors Related to Obesity
• Food producers and the "Fast Food“
industry - if they’re successful, we all eat
more
Childhood Obesity
• The growth of the fast food industry and
increasing portion sizes make it easy for
children to overeat
Supersize Me
Childhood Obesity
• “A large fast food meal (double
cheeseburger, French fries, soft drink,
desert) could contain 2200 kcal, which…
would require a full marathon to burn off”
– Ebbeling CB, Pawlak DB, Ludwig DS. Childhood obesity:
public health crisis, common sense cure. Lancet
2002;360:473-82.
Childhood Obesity
• On days that children and youth eat fast
food – they consume an extra 126
kcals/day (P<0.0001)
– Bowman S, Gortmaker SL, Ebbeling CB, Pereira MA,
Ludwig DS. Effects of fast food consumption on energy
intake and diet quality among children in a national
household survey. Pediatrics, in press.
Twenty Worst Foods in America
Childhood Obesity
• Sugar-sweetened beverages contribute
to childhood obesity incidence
Childhood Obesity
• “For each additional serving of sugar
sweetened beverage consumed, both BMI
(0.243 kg/m2; P=0.03), and incidence of
obesity (odds ratio 1.60; P=0.02)
increased.”
– Ludwig DS, Peterson KE, Gortmaker SL. Lancet 2001,
357:505-8
Childhood Obesity
• Television and video/film production and
distribution industry - if they’re successful
we all watch more
Now
• Advertisers constantly telling us to "eat this
now".
• Obesity increases as industrialization
increases.
A Widening Problem
• In a historical first, there are now as many
overnourished people as undernourished
around the world.
Why are we fatter?
• Here's the recipe for obesity on such a
global scale:
– Take technology—cars, washing machines,
elevators—that reduces physical exertion.
– Increase calorie consumption, courtesy of
increasing prosperity.
A Widening Problem
• Add television, computers and video
games.
• Stir in the intensive marketing of candy
and fast food, and you have the makings
of an epidemic.
A Widening Problem
• In countries where the food supply has
been unstable, people are getting fat
despite far less abundance than in the
United States.
A Widening Problem
• The implication?
• Newly industrialized nations in Asia,
Africa, the Caribbean, and Latin America
may develop even higher rates of obesityrelated health problems than in the U.S.
A Widening Problem
>24%
20-24
15-19
10-14
0-9
No data
A Widening Problem
• North America
States with the highest obesity rates—Mississippi and
Alabama—are in the South. The more affluent and
outdoorsy western states of Colorado and Utah have the
lowest rates.
South America
As Latin America becomes more developed,
supermarkets stocked with processed foods have
become the norm, rising from 20 percent of food retail
during the 1980s to 60 percent in 2000.
A Widening Problem
• Europe
Candy, fast food, and sweetened cereals account for
more than half the food ads in ten European Union
nations. In the U.K. snack food consumption rose nearly
25 percent in five years.
Africa
In some parts of Africa obesity afflicts more children than
malnutrition. In Tunisia the urban population is shifting
from traditional healthy whole grain breads to white
bread.
A Widening Problem
• Asia
In Shanghai, roads once filled with pedestrians and
cyclists are now congested with cars. KFC opened a
drive-through restaurant in Beijing in 2002, with more to
come.
Oceania
Pacific Islanders have always valued hefty physiques.
Now their shift away from local foods to a high-fat,
Western diet has made them among the world's fattest
people
Now
• The Puget Sound ferries in Washington
have increased the width of their seats
from 18 to 20 inches to allow squeeze-in
room for bigger bottoms.
Now
• In Colorado, an ambulance company has
retrofitted its vehicles with a winch and a
plus-size compartment to handle patients
weighing up to half a ton (1000 lbs).
Now
• An Indiana manufacturer of caskets now
offers a double-oversize model - 38 inches
wide, compared with a standard 24 inches.
Discrimination
• In one study at Michigan State University,
undergraduates said they would be more
inclined to marry an embezzler or cocaine
user than an obese person.
Discrimination
The Stigma of Childhood Obesity
Can be devastating…
• An obese child’s quality of life is similar to
the life of a child diagnosed with cancer,
which has been determined as the lowest
quality of life score.1
The Stigma of Childhood Obesity
can be devastating…
• Adolescents who are teased about their
weight are 2 to 3 times more likely to have
suicidal ideation and attempts compared
to adolescents who are not teased about
their weight. 2
The Stigma of Childhood Obesity
Can be devastating…
• Obese children and adolescents are 4
times more likely to experience impaired
school function when compared with
healthy children and adolescents. 1
• Obese children and adolescents have
been found to miss an average of 4.2 days
of school during the month. 1
It starts early…
• Low self esteem is not a characteristic in
inner city obese African American children
or obese preschool children. 3
• Levels of self esteem of preschool children
do not differ between non obese and
obese children, but upon entering school
this feelings change substantially. 3
Negatively affects school aged
children and adolescents…
• 4-11 year old children describe obese peers has
“ugly”, “selfish”, “lazy” “stupid”, “dishonest”,
“socially isolated” and subjects of teasing
compared to their average weight peers who
were described as “clever”, “healthy”,
“attractive”, “kind”, “happy”, “socially popular”
and a “desirable playmate”. 4
• Overweight adolescents are more likely to be
isolated and peripheral to social networks then
their normal weight peers. 5
Negatively affects school aged
children and adolescents…
• Social marginalization is more pronounced
in white non Hispanic adolescent girls. 5
• 90% of 9-11 year old overweight children
believe that teasing and harassment from
their peers would end if they could lose
weight and 69% felt that if they were
thinner they would have more friends. 6
It is also seen in homes, schools
and clinical settings…
• 30.0% of adolescent girls and 24.7% of
adolescent boys report being teased about their
weight by their peers. 2
• 28.7% of adolescent girls and 16.1% of
adolescent boys report being teased about their
weight by someone in their families. 2
• 14.6% of adolescent girls and 9.6% of
adolescent boys report being teased about their
weight by both their peers and family members.2
It is also seen in homes, schools
and clinical settings…
• Parents communicate to their children
negative stereotypes about obese
children. 7
• Parents of overweight children are
criticized and feel that they are guilty and
to blame for their child’s obesity. 6
• On implicit and explicit measures, health
professionals labeled obese people as
“lazy”, “stupid” or “worthless”. 8
Perception vs Reality
Who do we think we are or strive to be?
vs
Who we actually are?
Mr and Ms America?
Mr. And Ms. America
Conan the Governor
Jack Nicholson
Jack Nicholson
Denise Richards
• What this leads to is body disatisfaction
Eating Disorders
Progress?
• By contrast, among people who still live in
conditions most like those of our distant
Stone Age ancestors - Maku or Yanomami
of Brazil - there is virtually no obesity at all.
Modal Travel in Urban Areas:
Europe and North America Percent of Trips by
Mode
Country
Bicycle
Netherlands
Germany
England
Italy
Canada
USA
30
12
8
5
1
1
Walking
Public
Transport
Car
18
22
12
28
10
9
5
16
14
16
14
3
45
49
62
42
74
84
Transportation Quarterly 1997; 51:31
Distribution of Hours of TV Per Day:
NHES Youth Aged 12-17 in 1967-70 and
NLSY Youth Aged 12-17 in 1990
35
30
25
Percent
Distribution
20
15
NHES 1967-70
NLSY 1990
10
5
0
0-1
1-2
2-3
3-4
4-5
TV Hours (Youth Report)
5+
Tsunami of Health Care
Tsunami of Health Care
Cardiovascular Disease
Diabetes Mellitus
Glucose Intolerance
Overweight and Obesity
Sedentary Lifestyle