obesity

Question 1

what is obesity?

Answer 1

Obesity is a chronic, life-threatening disease
An excessive accumulation of body fat sufficient to impair health

Independent risk factor or aggravating agent for at least 30 common health conditions

Question 2

classification of obesity

Answer 2

normal - BMI - 18.5-24.9
overweight -BMI - 25-29.9
obese - 30-34.9
severe obese- 25-39.9
morbidly obese - equal or over 40

Question 3

what other conditions can obesity effect

Answer 3

• heart disease
  cancer
  stroke
  liver disease
  reproductive complications
  depression/anxiety
  sleep problems
  asthma
  type 2 diabetes

Question 4

what causes obesity

Answer 4

inidivual life chouce

society - cheap food, adverts, availaibity, work from home

determined by genetics

Question 5

how can you regulate weight

Answer 5

energy intake = energy outake

Question 6

what does energy balance mean
negative
positive

Answer 6

“State in which energy intake, in the form of food and /or drinks, matches the energy expended”

Positive energy balance
Energy in > energy out
Results in weight gain

Negative energy balance
Energy in < energy out
Results in weight loss

Question 7

what is yo-yo eating and BMR

Answer 7

Weight loss

Loss of muscle mass

Reduced BMR

Reduced requirements

Question 8

what is the barkers hypothesis

Answer 8

“Adverse environments in foetal life and early childhood establish increased risk of disease in adult life”

Under-nutrition in gestation induces programming of the pancreatic beta cells, muscle, liver, adipose tissues and neuroendocrine axis

Mismatch of poor prenatal environment and rich postnatal environment leads to maladaptation

Increases risk of obesity, glucose intolerance and coronary heart disease in adult life

Question 9

evidence for genetic influence
familial aggregation
twin studies

Answer 9

Familial aggregation
Familial clustering of obesity in families

Twin studies
Greater concordance among monozygote compared with dizygote twins

Question 10

what does genetic factors influence

Answer 10

body size and shape
body fat distribution
metabolic rate
brain chemistry

Question 11

what does thritfy metabolism gene allow
what is it

Answer 11

Thrifty metabolism gene allows for  fat storage to protect against famine

Cycle of feast and famine
Those that were better at fuel storage or utilization more likely to survive during famine
Over generations, we developed genetically to be exceptionally efficient at the intake and utilization of fuel

Question 12

probability of getting obesities
no parets obese
1 parent
both parent

Answer 12

no parent - 10 %
1 parent - 40%
2 parents - 80%

Question 13

what is the energy homeostatis system

Answer 13

The energy homeostasis system:
is precisely regulated across the lifetime of an individual
promotes stability in the amount of body energy stored in the form of fat

Question 14

2 types of feedback signals

Answer 14

There are two types of feedback signals:
Short-term
Meal-to-meal basis - determines amount of food ingested in a single meal
Satiety factors include nervous signals initiated in the GI tract

Long-term
Work over periods of weeks to years to regulate our energy intake & expenditure
Modulated by adipose tissue mass; major mediators are leptin and insulin

Question 15

what is leptin

Answer 15

Secreted by adipocytes in proportion to the amount of stored fat
Primary way brain knows how much body fat is stored

Regulates long term body weight rather than short term appetite

Diurnal variation: peak at night
Acts in the CNS to suppress food intake

Question 16

gut hormones -roles
cholecytoskin
secretin
GIP
motolin
ghrelin
gastrin
insulin and glucogen
pancreatuc polypeptide
amylin
GLP-1
GLP-2

Answer 16

cholecytoskin - gall bladder contraction, gastrointestinal motility, pancreatic exocrine, secretion

secretin - pancreatic exocrine, secretion

GIP - incretin activity

motolin - GI MOTILITY

ghrelin - hunger, growth horomone

gastrin - acid secretion

insulin and glucogen- glucose homeostatis

pancreatic polypeptide - gastric motility, satitation

amylin - glucose homesostatis, gastric motality

GLP-1 - incretin activity, satitation

GLP-2 - GI motality and strengyth

ocyntomodulin - satitation, acid secretion

PYY (3-36) - satitation

Question 17

what is gherlin

Answer 17

Peptide hormone secreted by gastric mucosa
Levels rise just before meals and fall after
Increases food intake
Ghrelin administration in rats strongly stimulates feeding
High Ghrelin levels in Prader-Willi syndrome
Orexigenic (appetite stimulating) effects of ghrelin mediated through hypothalamus
Stimulates NPY neurons

plasma ghrelin rises with hunger

Question 18

what is congnitive influences

Answer 18

Cognitive Influences = presence of others, favourite foods, time of day, free/abundant food, mood, stress.

Question 19

Conclusion

Appetite is a process controlled by several neural, humoral and psychological factors

Systems are designed to maintain a stable body weight despite huge variations in day-to-day energy intake and expenditure

Regulation of energy balance primarily acts to protect us against starvation so with the changes to our environment over recent years, we are becoming increasingly obese as a nation

Genetically-based variations determine our susceptibility or resistance to an obesogenic environment and the ease with which people are able to lose weight

Our current understanding of weight regulation should encourage healthcare professionals to:

“make war on obesity, not the obese”

Question 20

what is visceral adiposity

Answer 20

: fat as an endocrine organ

Question 21

relative risk of health problems

Answer 21

greatly risk (over 5)
diabetes
gall bladder diswase
hypertension
dyslipidemia
sleep apnoea
breathlessness
nonalchoholic fatty liver disease

mod risk (2-3)
- CHD
-osteoarthiritis (knees)
hypdfuricaemia and gout
-gastro oesophageal reflux disease

increased (1-2)
- cancer
lower back pain
impaired fertility
increased anaesthetic risks
obstetric complications

Question 22

what is obstructive sleep apnoea

Answer 22

Intermittent cessation of breathing during sleep due to the collapse of the pharyngeal airway, resulting in multiple apnoeic or hypopnoeic events

-normal
snoring
sleep apnoea

Question 23

link between asthma and obesity

Answer 23

Robust epidemiological data links obesity with an increased risk of asthma – mechanism unknown
Related to increased inflammation
Adverse effect on lung function

Question 24

cancer

Answer 24

Adipose tissue is an active endocrine organ
Mechanisms by which adipose tissue may influence cancer risk:
Production of sex steroid hormones (e.g., oestrogen, androgens)
Effects on insulin sensitivity and production of insulin-like growth factors
Actions on other hormones in adipose tissue (e.g., leptin, adiponectin)
Increases in oxidative stress and chronic low-grade inflammation that affect the body’s immune response

Question 25

obesity and covid

Answer 25

Obesity linked with large significant increases in morbidity & mortality from COVID‐19 (Popkin et al, 2020).

Public Health England Report:
Excess weight can increase risk of serious illness & death from COVID-19.

Question 26

treatment options

Answer 26

Behavioural Model - Behaviour change
Diet
Exercise

Medical Model - Medical management
Pharmacological management
Surgical management

Question 27

shat are the pharmacological management of obesity
role

Answer 27

Orlistat/Alli
Manydifferent types of anti-obesity medicines have been tested in clinical trials, but the only one that has proved to be safe and effective is orlistat.
Reduce fat absorption
Eating fat causes anal leakage
Can cause substantial weight loss

Question 28

what are the possible surgical management

Answer 28

vertical sleeve gastrectomy
ajustable gastric band
gastric bypass

Question 29

conclusion
Obesity is a chronic life-threatening disease with significant medical, psychological, social and economic consequences
It substantially increases mortality and morbidity mainly by increasing the risk of developing diabetes, hypertension and cardiovascular disease
It also plays a role in cancer, reproductive health and mental health
The majority of the adverse effects associated with obesity can be reversed or attenuated by weight loss which should be an integral part of the treatment of these morbidities