Energy Balance and Obesity

Question 1

what are the major sources of stored energy

Answer 1

Triacylglycerol and glycogen
minor contribution from protein

Question 2

What is the most concentrated form of stored energy in animals?

Answer 2

Triacylglycerol: fatty acids must be released to be used to generate ATP

Question 3

Energy content of TG, protein, carbs

Answer 3

37 kJ/g for TG compared to 17 kJ/g
for protein and 16 kJ/g for carbohydrate

Question 4

Why are TG such an efficient energy source

Answer 4

Fatty acids of TG are highly reduced
TG are stored in an anhydrous form

Question 5

What does an excess of TG result in

Answer 5

obesity

Question 6

which province has the highest obesity rate in Canada

Answer 6

Sask 48%

Question 7

BMI index

Answer 7

Weight/Height^2
(kg,m)
18-24: normal
25-29: overweight
>30: obese
BMI underestimates obesity

Question 8

What is obesity

Answer 8

A condition where a person has accumulated so much body fat that it has a negative effect on their health

Question 9

How odes fructose contribute to obesity

Answer 9

Used as a food sweetener
Fructose is lipogenic
There is no feedback for fructose
fructose converts to TG in an unregulated manner
Fructose bypasses phosphofructokinase which is the regulatory step in glycolysis. Fructose also tends to create more fatty acids because it is lipogenic. It activates ACC and FAS

Question 10

What is Ghrelin? Response in response to weight loss

Answer 10

Hunger hormone produced by gastrointestinal tract
relesaed when your stomach is empty
in response to weight loss , body tries to get back to orginal weight and stimulates ghrelin

Question 11

What does you body do in response to caloric deprivation

Answer 11

Reduction in energy expenditure
Increased hunger

Question 12

Function of insulin

Answer 12

Stimulates uptake of glucose from circulation into tissues, inhibits breakdown of fat, stimulates production of fat

Question 13

how is excess glucose stored as fat

Answer 13

Glucose–>Acetyl CoA–> Citrate–> Acetyl CoA –> Fatty acid–> TG
Converts excess glucose to fatty acids through the TCA cycle to be stored as TG

Question 14

why is rate of obesity increasing

Answer 14

Increase in energy consumption without an increase in energy expenditure

Question 15

how does your body react when you use caloric deprivation to promote weight loss

Answer 15

Reduction in energy expenditure and incresaed hunger

Question 16

Why is periodic fasting effective

Answer 16

allows insulin levels to fall and activate lipolysis and decreases body weight

Question 17

What are some health risks of obesity

Answer 17

Diabetes, CV disease, cancers, back pain, kidney failure, stroke, infertility, osteoarthritis, gallstones

Question 18

What was the minnesota starvation experiment

Answer 18

36 men were put on a semi-starvation diet
Results:
Men lost weight
Obsessed with food, protective of their meals
Sever psychological problems
could not keep warm due to decreased metabolic rate
Excessive eating when experiment was finished (regained weight)