Obesity is a global health issue, defined as abnormal or excessive fat accumulation that may impair health. According to the WHO, in 2005 over 1.6 billion adults were overweight and 400 million were clinically obese, numbers that are expected to surge significantly by 2015. Obesity prevalence varies widely between countries but is rising almost everywhere, posing serious health risks like increased chances of diseases such as cardiovascular disease and diabetes. Explanations for the global rise of obesity include nutrition transitions to highly processed diets and increasingly sedentary lifestyles in many societies. The WHO recognizes obesity as a global epidemic with over 2.3 billion people projected to be overweight by 2015.
2. Statistics
According to the World Health Organization, in 2005
1.6 billion adults were overweight
400 million people worldwide were clinically obese. By 2015, that
number is estimated to surge to 700 million.
At least 2 million children <5 years old were overweight
35% children are overweight in the USA
7. Measuring Obesity - BMI (Body Mass Index)
Weight (kg)2
Height (m)
Populations (Asia) that risk of chronic disease increases
with BMI >22
8. BMI Less than 20 — Under Weight
BMI 20-25 — Normal Weight
BMI 25-30 — Over Weight
BMI 30-40 — Obese
BMI Over 40 — Severely Obese
The spread from 20-25 shows that what is normal covers quite a big range.
This is because ‘normal’ weight for height covers both men and women, and
people of different shapes and body composition. A man would normally be
expected to have a higher BMI than a woman of the same height, because
men tend to have more muscle than women (women naturally have more
fat) and muscle weighs more per square inch than fat. For the same reason a
slim, muscular woman will have a higher BMI (i.e. weigh more) than a slim,
not very muscular woman of the same height.
12. Why is obesity increasing?
1. A global shift in diet towards increased intake of energy-dense
foods that are high in fat and sugars but low in vitamins, minerals
and other micronutrients.
2. A trend towards decreased physical activity due to the increasingly
sedentary nature of many forms of work, changing modes of
transportation, and increasing urbanization.
19. What are the Health Consequences?
Cardiovascular disease (heart attack, stroke)
Diabetes
Musculoskeletal disorders (esp. osteoarthritis)
Some cancers (endometrial, breast, colon)
Life expectancy reduced by 14 yrs for obese smokers compare to
normal weight non smokers!
Life expectancy reduced by up to 9 years.
20. • The overall cost of obesity to the NHS is currently around £1bn, with
a further £2.3bn to £2.6bn for the economy as a whole.
• Professor Colin Waine, chairman of the National Obesity Forum,
said the figures revealed a "public health timebomb".
• "This is serious news because obesity in adolescence is associated
with the premature onset of Type 2 diabetes and cardiovascular
diseases.
• "It really augurs very badly for the future health of the population as
these children move from adolescence to adulthood.
• "This will have a significant impact on longevity and we are in
danger of raising a generation of people who have a shorter life
expectancy than their parents.
26. More in demand…
• Triple width coffins (up to 300kg)!!
• Airlines recalculating payload weight
• New reinforced hospital beds by NHS
27. How can the burden of overweight and obesity be
reduced?
• At the individual level, people can:
• achieve energy balance and a healthy weight;
• limit energy intake from total fats and shift fat
consumption away from saturated fats to unsaturated
fats;
• increase consumption of fruit and vegetables, as well as
legumes, whole grains and nuts;
• limit the intake of sugars; and
• increase physical activity - at least 30 minutes of regular,
moderate-intensity activity on most days. More activity
may be required for weight control.
41. What is obesity?
• Obesity is abnormal or excessive fat
accumulation that can impair health
• Obesity exists when a person has a
body mass index (BMI) of 30 or more
• It is considered a medical condition in
most of the world, but in 2013 the
American Medical Association
reclassified obesity as a disease
BMI is a function of both
weight and height
42. Impacts on health
•Obesity is important because it has
significant health impacts:
•It increases the risk of developing non-
communicable diseases
•It reduces life expectancy
•It has a economic consequences for
health provision as the costs of managing
obesity rise
43. Global patterns
• Obesity varies between countries, from
3.5% of men overweight/obese in Eritrea
in 2010 to 97% on the Pacific island of
Nauru.
• However, in almost every type of country
and region it is rising (see table).
• In some countries, such as China, the
increase in overweight/obesity is startling
in a short time frame.
• In others, such as the USA, UK and
Mexico prevalence rates are very high.
% males
overweight/obese
(WHO data) 2002 2005 2010
Afghanistan 11.2 12.7 15.6
Argentina 70.1 73.1 77.7
Australia 69.7 72.1 75.7
Bangladesh 5.9 6.7 8.4
China 27.5 33.1 45
Ethiopia 7.4 7.8 8.6
UK 62.5 65.7 67.8
Haiti 13 15.1 19
India 15 16.8 20.1
Kenya 6.5 6.9 7.7
Mexico 64.6 68.4 73.6
USA 72.2 75.6 80.5
44. Global patterns
• Obesity is highest in North America,
North Africa and the Middle East, and
many Pacific islands.
• South Africa and Venezuela are also
‘hotspots’.
• Levels in Europe and Latin America are
similar — despite differences in levels
of development.
• As might be expected, sub-Saharan
Africa and Asia have the lowest
prevalence, although some of the
fastest growth rates.
46. Development level and obesity
• Although there is some evidence of a
‘North–South divide’ in obesity, the
pattern is complex.
• As the scattergraph shows, wealthy
countries such as the Netherlands,
Canada and the USA have different
levels of overweight/obese males.
• Lower-income countries such as Egypt,
Samoa and Mexico have levels equal to
or even higher than those in developed
countries.
47. Explanations
•Explanations of obesity are complex:
•On many Pacific islands the abandonment of traditional farming and
fishing has given way to a reliance on imported processed meat. Girth
is seen as a signof social and economic status.
•In Europe and North America, a high-fat, processed and fast-food
diet has combined with increasingly sedentary office jobs and lifestyles.
•In much of developing Asia and Latin America the nutrition
transition and rural–urban migration have combined to increase fat,
sugar and protein in diets at the expense of cereals and vegetable
fibre. In cities people labour at desks and workstations rather than in
the fields.
•In the Middle East oil-rich states, wealthy people have domestic
servants so do very little in the way of household chores.
Increased car use
Fast food
Larger portions
Cultural appreciation
of plumpness
Sedentary lifestyles
TV and video games
Urbanisation Decline
in farm employment
Processed food
Poor education
Food marketing
48. The ‘globesity’ crisis
• The World Health Organization (WHO)
has referred to a ‘global obesity
epidemic’ and the world’s media to
a‘globesity crisis’
• The crisis is worst in middle-income
developing countries, like Mexico
• Obesity levels are high but so are
infectious diseases
• This is a ‘doubleburden’ on the
healthcare system.
• Obesity was recognised as a global
epidemic by the WHO in 1997.
• Over 1.5 billion people worldwide are
currently overweight and 500 million are
obese.
• The WHO projects that by 2015, 2.3
billion adults will be overweight and more
than 700 million will be obese.
• About 60% of obese people are women
and 40% are men.