Obesity is defined as having a body mass index (BMI) over 30, which is determined by dividing weight in kilograms by height in meters squared. It occurs when more calories are consumed than burned through physical activity. There are multiple causes of obesity including biological factors like genetics and hormones, behavioral factors like eating habits and physical activity levels, and environmental factors like technology use and food availability. Obesity increases the risk of chronic diseases, reduced quality of life conditions, and psychological issues. Proper nutrition can act as a protective factor against disease when combined with physical activity, though individual factors also contribute to health risks.
2. OBESITY - WHAT IS IT?
Presence of excess body fat
Determined by body mass index (BMI)
BMI = weight (kg) / height (m) 2
BMI of 25 to 29.9 = Overweight
BMI of over 30 = Obese
Being overweight is associated with a higher
risk of disease, particularly if the body fat is
concentrated around the abdomen.
3. CAUSES OF OBESITY
Obesity is a complex disorder with multiple
interactive causes
Obesity occurs when a person consumes more
kilojoules (energy) than he or she burns
(through physical activity)
The cause of the imbalance between kilojoules
input and output may differ from person to
person
4. CAUSES OF OBESITY - BIOLOGICAL FACTORS
Gender; women carry more
fat, but men carry more fat
around stomach, therefore
greater risk CVD
Age; maintenance of body
weight becomes more
difficult with age
Genetics; including
inheritance of specific body
type
5. CAUSES OF OBESITY - BIOLOGICAL FACTORS
Hormonal factors; BMR; basal
metabolic rate
- Your basal metabolic rate, or BMR, is
the minimum calorific requirement
needed to sustain life in a resting
individual. It can be looked at as
being the amount of energy
(measured in calories) expended by
the body to remain in bed asleep all
day!
- Thyroxin (hormone produced by the
thyroid gland) is a key BMR-regulator
which speeds up the metabolic
activity of the body. The more
thyroxin produced, the higher the
BMR.
6. CAUSES OF OBESITY - BEHAVIOURAL FACTORS
Eating behaviour; food choices, cultural
influences, emotions, eating habits, attitudes
Lack of Physical activity; the amount and
intensity of exercise
7. CAUSES OF OBESITY
- ENVIRONMENTAL
FACTORS
Technology; has increased time being
sedentary (not active), computers, remote
controls etc
Industrialisation; increased availability of
high fat, sugar and energy dense foods
Urbanisation; people living environment that
promotes sedentary lifestyles eg. Take away
food outlet convenience
8. OBESITY - A RISK FACTOR FOR…
Life threatening chronic
illness; CVD, type 2
diabetes, hypertension,
stroke, cancers
Non-fatal debilitating
conditions; reduce quality
of life, gall bladder disease,
respiratory difficulties,
infertility and osteoarthritis
Psychological problems;
depression, low self esteem
9. ROLE OF NUTRITION AS A PROTECTIVE FACTOR
FOR DISEASE
An individuals nutrient and food
intake can have both short-term and
long-term consequences on their
health.
Food choices can act as a protective
factor against certain diseases.
Some commonly consumed foods are
energy dense, rather than supplying a
range of nutrients
Regular consumption of these foods
decreases the quality of nutrient
intake.
10. CONTINUED
The associated level of
protection foods offer, is
very closely linked with
other factors such as;
- Physical activity
- Biological influences
- Genetics (including
gender)