2. Obesity
Dr. Makwan Jaff
M.B.Ch.B

3. Obesity
-is an excess of body fat.
-Result from an imbalance between the amount
of energy consumed in the diet and the amount
of energy expended through exercise and bodily
functions.

6. Statistics
In UK :
7% of adults were obese in 1980.
16% in 1995.
25% in 2010.
66% of adults were overweight in 2010
In USA :
30% of adults were obese in 2010

7. Complications
-At age 40 years it can reduce life expectancy by up to 7
years for non-smokers and by 13 years for smokers.
-Coronary heart disease is the major cause of death.
Obesity has little effect on life expectancy above 70 years
of age, but the obese do spend a greater proportion of
their active life disabled.

12. Body fat distribution
-Increased intra-abdominal fat causes (central,
abdominal, visceral, android, apple-shaped) obesity
which is more common in men and is more closely
associated with DM type 2, the metabolic syndrome and
CV Disease.
-Increased subcutaneous fat accumulation causing
‘generalized’ (gynoid, pear-shaped) obesity which is more
common in women.

14. Etiology
Weight tends to increase throughout adult life, as BMR
and physical activity decrease.
we find humans live in an obesogenic environment that is
the circumstances encourage people to eat more and
exercise less. This includes the availability of cheap and
heavily marketed energy-rich foods, the increase in labor-
saving devices (e.g. lifts and remote controls) and the
increase in passive transport (cars as opposed to walking,
cycling, or walking to public transport hubs).

16. Susceptibility to obesity
-Familial life style.
-The pattern of inheritance suggests a
polygenic disorder(BMR variation)
-A few rare single-gene disorders have been
identified that lead to severe childhood
obesity.

18. Assessment
-BMI
-Waist circumference of > 102 cm in men or
> 88 cm in women indicates that the risk of metabolic
and CV complications is high.
-It is important to consider ‘pathological’ eating behavior
(as binge eating disorder).
Alcohol is an important source of energy intake.

20. Management
-The health risks of obesity are largely
reversible.
-Initiatives include promoting healthy eating
in schools, enhancing walking and cycling
options for commuters and liaising with the
food industry to reduce energy and fat
content and to label foods appropriately.

21. Lifestyle advice
-Behavioral modification to avoid some of the
effects of the ‘obesogenic’ environment is the
cornerstone of long-term control of weight.
-Maximizing physical activity in the daily routine
(walking rather than driving to work), since this is
more likely to be sustained.
-Alternative exercise (e.g. swimming) if
musculoskeletal complications prevent walking.

22. Lifestyle advice
-Changes in eating behavior (food selection,
portion size control, avoidance of snacking, regular
meals to encourage satiety and substitution of
sugar with artificial sweeteners.
-Regular support from a dietitian or attendance at
a weight loss group.

23. Weight loss diets
Daily energy content should be a minimum of 1.65
MJ (400 kcal) for women of height < 1.73 m, and
2.1 MJ (500 kcal) for all men and for women taller
than 1.73 m. Side effects are a problem in the
early stages and include orthostatic hypotension,
headache, diarrhea and nausea.

25. Drugs
The side-effect has limited the use of many agents.
Orlistat is only currently licensed for long-term use.
It inhibits pancreatic and gastric lipases which decreases
the hydrolysis of ingested triglycerides, reducing dietary
fat absorption by 30%.
Side effects: fat malabsorption on the gut: loose stools,
oily spotting, faecal urgency, flatus and malabsorption of
fat-soluble vitamins(A, K, E, D).
Its taken with each of the 3 meals/day.

26. Surgery
-Bariatric surgery is the most effective long-term
treatment.
-Only experienced surgeons should undertake such
procedures in collaboration with a multidisciplinary team
and can be performed laparoscopically.
The mechanism of weight loss is disrupting the release of
ghrelin from the stomach or promoting the release of
other peptides from the small bowel, thereby enhancing
satiety signalling in the hypothalamus.

29. Treatment of additional
risk factors
Obesity must not be treated in isolation and other risk
factors must be addressed, including smoking, excess
alcohol consumption, diabetes mellitus, hyperlipidemia,
hypertension.

30. References
P. Hanlon , M. Byers , J.P.H. Wilding , H.M. Macdonald,
Environmental and nutritional factors in disease(Chapter 5)
, Brian R. Walker , Nicki R. Colledge , Stuart H. Ralston , Ian
D. Penman , Davidson’s Principles and Practice of Medicine
22nd edition (2014)

31. Thanks for listening