182. Starvation and Metabolic Adaptation

Question 1

How does core body temp respond to starvation?

Answer 1

Decreases

Question 2

Hormones that __ during starvation:

• leptin
• insulin
• T3/T4
• LH, FSH
• Estrogen, testosterone

Answer 2

Decrease

Question 3

Volitional reduction in energy intake (below needs), with adequate intake of protein and micronutrients

Answer 3

Caloric restriction

Question 4

Primary deficit is in protein intake

Low or normal body weight
- edema may mask weight loss

Distended abdomen

Fatty liver/liver dysfunction

Marked hypoalbuminemia

Skin and hair changes

Answer 4

Kwashiorkor

Question 5

__ changes seen in normal volunteers during __:

• preoccupation with food
• hoarding and stealing food
• abnormal taste preferences
• binge eating
• depression, apathy, irritability, and other personality changes

Answer 5

Behavior

Starvation

Question 6

Determinants of __:

• Body composition
• Age (decreases w/ age)
• Gender (women have higher in luteal phase)
• Nutritional status
• Health status

Answer 6

BMR

Question 7

Metabolic adaptation to starvation spares __ mass

- d/t use of alternative fuels: FFA and KB

Answer 7

Lean

Question 8

Life-threatening condition that can occur during eating a lot in an individual with malnutrition who previously was unable to eat

Electrolyte abnormalities may occur when the availability of glucose produces shifts of electrolytes into cells for use in synthesis of ATP and new tissue

• arrhythmias and decreased cardiac contractility can result
• heart size is reduced due to malnutrition and eating once again leads to increased circulatory blood volume –> heart failure can result

Answer 8

Refeeding Syndrome

Question 9

On day _ of starvation, one switches from main source of fuel being glucose to fatty acids and ketones
- allows us to survive longer

Answer 9

3

Question 10

Enzyme that is sensitive to insulin

Activated when insulin levels are low to produce free fatty acids
- site of action is in adipose tissue

Kind of like Type 1 DM

Answer 10

HSL

Question 11

Close to pure-simple starvation

Primary deficit is in low calorie intake

Very low body weight

Wasted appearance with loss of both fat and muscle

Liver function is usually normal

+/- hypoalbuminemia

Dry, inelastic skin

Answer 11

Marasmus

Question 12

Can be seen in babies when they are removed from breastfeeding all of a sudden
- loss of protein

Can also be seen in ppl w/ GI surgery that hurts protein absorption or ppl on low protein diets

Answer 12

Kwashiorkor

Question 13

__ increases in illness d/t:

• catecholamines and sympathetic nervous system stimulation
• fever
• inflammation and cytokines

May increase by 30-100% or more

Answer 13

BMR

Question 14

2 main ways to provide nutrition support to patients who can’t or won’t eat

Answer 14

Enteral nutrition (G-tube)
Parenteral nutrition (IV)

Question 15

Where do ketone bodies come from?

Answer 15

Liver

Question 16

With weight loss, __ levels decrease in obese patients

Answer 16

leptin

Question 17

It has been postulated that decreased levels of __ leads to HPA axis activation of cortisol that leads to increase in free fatty acid production along with ketone bodies

Answer 17

Leptin

Question 18

2 substitutes for glucose that are used for energy in a starving state

Answer 18

Free fatty acids and ketone bodies

Question 19

In illness, you see increase __ __ d/t:

• inflammation and cytokines
• increased cortisol
• insulin resistance

Dietary needs may double in some patients

Answer 19

Protein metabolism

Question 20

What causes increased energy expenditure and markedly increased protein catabolism?

Glucose does not suppress protein catabolism in this case
- no protein sparing

Can present as cachexia

Differs from starvation

Answer 20

Illness

Question 21

Fuels used by the brain in late starvation

Answer 21

Ketone bodies and glucose

Question 22

Just __ g of dietary carbohydrate per day can suppress ketosis and gluconeogenesis
- protein sparing

Answer 22

100

Question 23

“Flaky paint” rash and depigmentation of hair are clues to a patient w/ what?

Answer 23

Kwashiorkor

Question 24

Becomes more important as a source of new blood glucose when starvation continues

Answer 24

Kidneys

Question 25

Hormones that increase during starvation (2 of them)

Answer 25

Ghrelin and glucagon

Question 26

Changes in \_\_ \_\_ during starvation: 
TEE: down arrow, down arrow 
BMR: down arrow, down arrow 
TEF: down arrow 
EEPA: down arrow, down arrow 

Disproportionately goes down more than we’d expect, not explained just by amount of weight loss

Answer 26

energy expenditure

Question 27

Occurs with illness; characterized by increased protein catabolism, induced by inflammatory cytokines

Answer 27

Disease-associated malnutrition (cachexia)

Question 28

Metabolic and hormonal changes with weight loss in __:

• Decreased:
  
  • energy expenditure
  • leptin
  • T3/T4
  • core body temp
• Increased:
  
  • Ghrelin
  • Muscular efficiency

Modified:
- Neural activity

Answer 28

Obesity

Question 29

Adipose produces __ in times of starvation that leads to:

- Free fatty acids being produced from adipose tissue and sent to muscle, liver, and kidney

Answer 29

HSL (hormone-sensitive lipase)