27.1 Biochem: Obesity and lifestyle choices Flashcards
What is the set point of human weight largely determined by?
Leptin levels
What is the relationship between obese people and leptin levels?
Obese have low sensitivity to leptin, often have high leptin levels
What is ‘pester power’?
An advertising tactic created by food companies (e.g. McDonalds including toys) to encourage children to pester their parents to buy the food
Was food company self regulation effective? Give a supporting example why/why not
NO
Coca-cola ad ‘dispelling myths’
What is the weight distribution between people in Melbourne’s Western (‘disadvantaged’) vs. Eastern suburbs
Average of 3kg heavier in disadvantaged areas
What proportion of their income do welfare recipients vs. top third of earners spend on food? Which kinds of food?
Welfare: Over 30% of income- cheap food
Top third: 9% of income-healthy food
What are the classifications for morbidity, obesity, normal weight and underweight (the BMI ranges)?
Morbid obesity: >40 Obese: 30-39.9 Overweight: 25-29.9 Normal weight: 18.5-24.9 Underweight:
How much volume are fat cells capable of carrying?
How many fat cells can we have?
Varying volume by 20 fold
Unlimited
What happens to fat cells after 6 months of reduced fat content?
How long does it take for a diet to be regarded as successful?
Some cells die
2 years
What is leptin? What produces it?
Cytokine, adipocytes produce it
What does leptin indicate? To where?
Leptin indicates to hypothalamus that fat stores are adequate and to reduce food intake
What does leptin stimulate?
What gene are we referring to?
Increased energy expenditure
‘ob’ gene
What peptide and melanocortin are important in appetite? Do they stimulate or suppress it?
NPY: Stimulates appetite
POMC: Decreases appetite
What is adiponectin? what secretes it?
A mix of anti-inflammatory peptide hormones
Adipocytes secrete
What does adiponectin stimulate? How does this affect circulating glucose levels?
AMPK (skeletal muscles and liver)--> fatty-acid oxidation/glucose uptake/lactate production activated gluconeogenesis (in liver) decreases--> increased glucose uptake into muscle--> reduced circulating glucose levels
