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Nutrition Exam 3 > Energy Balance & Body Composition > Flashcards

Flashcards in Energy Balance & Body Composition Deck (62)
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1
Q

What is the thermic effect of food/what are the components of energy output?

A

Our energy output - energy used in digestion, absorption, metabolism & storage of nutrients from food

**Metabolism (energy we use to breathe, regulate body temp, heart beat)

2
Q

What is an example of food with a low energy density? How does this affect feeling of fullness?

A

Vegetables/high fiber foods!

Increases satiation & satiety

(foods that provide less kcal/gram of food consumed)

3
Q

How much of the body’s total energy expenditure is represented by the Basal Metabolic Rate (BMR)?

A

60-70%

4
Q

Which type of adipose tissue can be broken down faster for use in thermogenesis?

A

Brown adipose

Highest percentages in babies, in adults it depends on location/gender/BMI (usually adults in cold climates with healthy BMI)

5
Q

In adipotoxicity, TNF-alpha, IL-6, and Resistin stimulate what process?

A

Lipolysis

6
Q

What is lipotoxicity?

A

Accumulation of free fatty acids in non-adipose tissue

7
Q

How do you diagnose someone with metabolic syndrome?

A

Need 3/5 components:

  • low HDL
  • high BP
  • insulin resistance (>110)
  • high triglycerides
  • high waist circumference

If patient is on medications to regulate BP, they only need 2/5

8
Q

What hormone controls hunger?

A

Ghrelin (controlled by hypothalamus)

9
Q

How do energy from heat combustion, digestible energy, and metabolizable energy differ?

A

Metabolizable energy < Digestible energy < Energy from Heat combustion

10
Q

What is the difference between appetite and hunger?

A

Appetite - desire to eat

Hunger - need to eat

11
Q

What foods have a higher energy density? How does this affect the feeling of fullness?

A

Starchy foods, pizza, fructose
(foods that provide more kcal/g of food consumed)

Decrease satiation & satiety

**Strong satiety effect once it reaches the SI

12
Q

What is the BMR (basal metabolic rate)?

A

Energy required to maintain life when body is at rest

13
Q

What are the major factors affecting BMR?

A

Higher BMR: males, tall/thin people, PMS hormones, Caffeine, fever, stress, extreme temperatures

Decreased BMR: fatty tissue, old age

14
Q

How much of the body’s TEE is represented by the Thermic affect of food (TEF)?

A

10%

15
Q

What major factors affect TEF?

A

Meal composition:

  • Proteins>Carbs>Lipids
  • Spicy foods increase metabolism by 33% for 3 hours after meal

Meal timing - energy expenditure is raised 30-90 min after a meal

16
Q

What is the difference between AT and NEAT?

A

AT = energy use during fitness exercise

NEAT = activities of daily living and energy expended during leisure activities (gum chewing)

17
Q

What factors affect AT?

A

Body size
Fitness level
EPOC = Increased metabolic rate that occurs after exercise has ceased

18
Q

What is the TEF of protein?

A

20-30% increased energy expendeture

19
Q

What is the TEF of lipids?

A

0-5% increased E

20
Q

What is the TEF of carbs?

A

5-10% increased E

21
Q

What is the TEF in a mixed macronutrient meal?

A

10%

22
Q

Describe the progression of positive energy balance in overnutrition.

A
  1. Fill glycogen stores
  2. Excess carbs turned into FA
  3. Dietary fat stored in adipocytes
  4. Less lipolysis
  5. Hypertrophy/Hyperplasia of adipocytes
23
Q

What is the difference between hypertrophy and hyperplasia in relation to adipocytes?

A

Hypertrophy - increase in size of adipocytes
Max size = 1mcg of fat/cell

Hyperplasia - increase in number of adipocyres

24
Q

T/F: Lipoprotein lipase is more active in obese individuals than lean individuals.

A

True

25
Q

Where is lipoprotein lipase more active in males vs females?

A

Males - abdomen

Females - Breasts, hips, thighs

26
Q

What is the difference between ‘apple’ and ‘pear’ shape?

A

Apple - MC in males, android-type obesity, more visceral fat, associated with more health risks

Pear - MC in females, gynoid-type obesity

27
Q

What are the characteristics of white adipose (WAT)?

A

Unilocular adipocyte
Release FFA when needed
Visceral & subcutaneous

28
Q

What are the characteristics of brown adipose (BAT)?

A

Multilocular adipocyte
Quick-access fuel for thermogenesis
High rates of active uncoupling proteins

29
Q

What is beige fat?

A

ALL adipose tissue has genes for BAT that can be accessed via cold stimulus in subcutaneous WAT

30
Q

T/F: BMI is a measure of body fat.

A

False - measure of appropriate weight based on height

31
Q

What is the range for a healthy BMI?

A

18.5-24.9

32
Q

What BMI is considered overweight?

A

25+

33
Q

What BMI is considered severely thin?

A

<16

34
Q

What are the 3 BMI categories for obesity?

A

Obese 1: 30-34.9

Obese 2: 35-39.9

Obese 3: 40+

35
Q

What are 3 better indicators of health (instead of BMI)?

A

Waist circumference (WC)

Waist to hip ratio (WHR)

Waist to height ratio (WHtR)

36
Q

What do you measure for a waist measurement?

A

Smallest part/halfway between iliac crest & bottom of lowest rib

37
Q

What do you measure for a hip measurement?

A

Measured at largest part, standing, without tissue indentation

38
Q

What is the healthy waist circumference?

A

Males - 40” or less

Females - 35” or less

39
Q

What is the healthy WHR?

A

Males - 0.95” or less

Females - 0.80” or less

40
Q

What is the healthy WHtR?

A

<0.5

41
Q

What comprises fat mass?

A

Essential fat

Storage fat

42
Q

What comprises fat-free mass/lean body mass?

A

Bone
Muscle
Fluid

43
Q

T/F: Subcutaneous fat is easier to lose than visceral fat.

A

False!

Very metabolically active, Increases lipotoxicity due to increased LPL activity

44
Q

What is the difference between adipotoxicity and lipotoxicity?

A

Adipotoxicity - Neg effects of storage of excess fat in adipose tissue

Lipotoxicity - Neg effects of storage of excess fat in non-adipose tissue

45
Q

What adipokine causes insulin resistance?

A

TNF-alpha

Also promotes beta cell apoptosis & stimulates lipolysis

46
Q

What adipokine protects against beta cell apoptosis?

A

IL-6

47
Q

What adipokine inhibits insulin release from beta cells?

A

Leptin

**Leptin resistance seen in many obese people

48
Q

Which adipokine is decreased in obesity?

A

Adiponectin

**Induces insulin sensitivity in muscle/adipose

49
Q

Which adipokine is increased in obseity?

A

Resistin

**Decreases muscle ability to take up FA

50
Q

How does the pancreas react to lipotoxicity?

A

beta cell failure

51
Q

How does the liver react to lipotoxicity?

A

non-alcoholic fatty liver disease

52
Q

How do the muscles react to lipotoxicity?

A

Insulin resistance (type 2 diabetes)

53
Q

How does the heart react to lipotoxicity?

A

Heart disease

54
Q

How is endothelium vasoconstriction affected by lipotoxicity?

A

HTN

55
Q

What pathway is decreased in lipotoxicity?

A

Beta-oxidation

56
Q

What are the pros/cons of using skinfold thickness to measure body composition?

A

Pros: Fast, inexpensive, noninvasive, user-friendly

Cons: less precise, only measures subcutaneous fat

57
Q

What are the pros/cons of using underwater weighing to measure body comp?

A

Pros: fairly accurate

Cons: Expensive, some error in calculations for density

58
Q

What are the pros/cons of using bioelectric impedance to measure body comp?
(Fat = poor conductor, muscle/organs = good conductors)

A

Pros: cheap, fast

Cons: less precise, more error, patient must be well hydrated, no caffeine/alcohol 24 hours prior, must not have exercised for 4-6 hours

59
Q

What are the pros/cons of using air displacement?

A

Pros: quick, portable

Cons: expensive, less accurate than underwater weighing or DEXA

60
Q

What are the pros/cons of using DEXA?

A

Pros: Accurate, reproducible, also determines bone density

Cons: expensive, requires training, x-ray exposure,

61
Q

What are the pros/cons of using MRI?

A

Pros: accurate, reproducible

Cons: expensive, time consuming

62
Q

What are the pros/cons of using waist circumference?

A

Pros: cheap, fast

Cons: More error/less precise