Starvation

Question 1

What is Starvation

Answer 1

it is the inability to obtain food for an longer period of time

Question 2

What is the main primary challenge ?

Answer 2

Primary challenge = provide enough glucose for the brain to maintain normal neuronal cell functions.

Question 3

Blood

Answer 3

Also remember: Red blood cells (erythrocytes) are dependent on serum glucose as a sole source of energy to generate ATP. Mature erythrocytes lack mitochondriaand are not able to utilize fatty acids for energy because fatty acid oxidation takes place in the mitochondrial matrix.

Question 4

What happens in stage 1 ?

Answer 4

Glucose is heavility relied on at this stage
Glycogen is made from glucose in the liver

Glycogen only lasts a few hours
• When used up fats and some proteins are broken down into glucose

After 24hrs :Body mechanims changes in two

 gluconeogenic pathway (liver and kidneys) Glucose for the brain & erythrocytes.  
Consequences of liver glycogen loss

2. Switch to using fatty acids as the primary metabolic fuel. spares whatever glucose is available for the brain and erythrocytes.

Question 5

WHAT HAPPENS IN STAGE 2

Answer 5

Fat becomes the primary energy source
 Liver breaks down fatty acids into ketone bodies
 After a week the brains starts to use ketones and glucose for energy INCREASE FROM 30 % TO 70 %

Glycolysis decreases.
• Oxaloacetate is decreased more than normal Inability to perform gluconeogenesis.
reduces activity of TCA cycle. -Acetyl CoA builds up and excess is converted to ketone bodies.

*Urine output drops after to 100-700 ml/day

Metabolic respnse ;
Blood glucose levels drop to (35 - 65 mg/dl). No clinical signs of hypoglycemia

• Nausea occurs in about 1/3 from ketone production from body fat breakdown

Question 6

What happens in Stage 3

Answer 6

Fats reserved are depleted

Body uses proteins as energy

Muscles rapidly deplete.

• Nonessential proteins are used up first.

Negative nitrogen balance is slow after 1 month

Skeletal muscle catabolism decreases rapidly

Needed only for cells that have to have glucose » Central nervous system » Red blood cells » White blood cells

Question 7

Overall Effect

Answer 7

Pancreas reduces insulin secretions
Metabolic rate is decreased.
– Many organs begin to shrink.

Villi in gut shrink which means less capacity to absorb nutrition.
 Total body shut down and DEATH.

For example, the heart of a healthy adult weights 11 to 14 ounces; in late starvation, the heart may shrink to 5 to 6 ounces. Intestines wither, making it impossible, for the body to digest food

Question 8

Malnutriton

Answer 8

inadequate intake of any of the required nutrients.

 Can even occur in an animal receiving large amounts of food, (not able to ingest, digest, absorb, or utilize food).

inadequate intake of any of the required nutrients.

Causes:  Injuries / poor teeth / parasitism / disease / foreign bodies in the digestive tract / tumors.  increased motility of the digestive tract.  inadequate food.

Question 9

Types of Malnutrition

Answer 9

Over nutrition

Too many calories leading to obesity, diabetes, hypertension and cardiovascular disease

• “Transition diets” now a consideration of WHO due to increase worldwide in chronic disease due to dietary change

Secondary Malnutrition

• Condition that prevents proper digestion or absorption
  • Often accompanies and exacerbates other types of malnutrition

Causes:
• Loss of appetite
• Alteration of normal metabolism (infection/fever; immune disease -HIV/AIDS)
• Prevention of nutrient absorption – Diarrheal infection causing changes in GI epithelium
• Diversion of nutrients to parasitic agents themselves: (Hookworms, tapeworms, schistosome worm, Malaria

Question 10

Micronutrition

Answer 10

Micronutrient Malnutrition • Dietary Deficiencies of – Vitamin A – Iodine – Iron – Others: Zinc, vitamins D, C, and Bs