Alterations in Energy Balance: Starvation, Obesity Flashcards
Basal metabolic rate is influenced by: 6 things
Age, Body Surface, Temperature, Sex, Degree of Nutrient Supply, Emotional State
25 y/o 65kg male has what BMR? With light physical activity, what is his total calorie needs in a day?
BMR 1680 kcal/day
With light phys activity, 2600 kcal/day
How is indirect calorimetry measured?
Measure exhaled CO2 and inhaled O2 in an isolated system
Some conditions with increased energy needs
pregnancy, fever, infection, wound-healing, trauma/burning injury, tumor, some medications
What are the target organs of energy regulation?
Liver, adipose tissue, muscle
How much protein mass does an avg 70kg person have
12kg
How much carb mass does an avg 70kg person have
0.2kg
How much fat mass does an avg 70kg person have
15kg
What are 3 stimulatory effects of insulin on the slide?
Enhances glycogen, protein, and fat synthesis
What are 2 inhibitory effects of insulin on the slide?
Inhibits lipolysis and gluconeogenesis
What are 3 stimulatory effects of glucagon and epinephrine on metabolism from the slide?
Enhance lipolysis, gluconeogenesis, and glycogenolysis
What are 2 stimulatory effects of cortisol on metabolism?
Enhances gluconeogenesis and proteolysis
ACTH, STH, and thyroid hormone all do what to fat?
enhance lipolysis
2 examples of substrate-level fat regulation:
- elevated glucose levels increase fat synth (increasing cytoplasmic citrate and NADPH concentrations, also providing a glycerophosphate source)
- elevated FFA levels at starvation (inhibit cellular glucose uptake, enhance glycogenolysis and gluconeogenesis)
How much kcal energy does an avg 70kg person’s fat hold?
100,000 to 150,000 kcal
How many days does it take for starvation to be “adapted”
3 days
Clinical conditions causing ketosis:
- Fasting, starvation
- untreated DM I -> DKA
- alcoholism
- ketogenic diet
- vomiting (mostly in children)
A ketogenic diet may help what 2 things (from slide)
Epilepsy and of course to lose weight
Which protein-energy intake deficiency in children has edema? which one does not?
Kwashiorkor has ascites/edema. low albumin level, fatty liver.
Marasmus: no edema. elevated glucocorticoid levels, less pronounced decrease in albumin levels
How high can the mortality rate for anorexia nervosa be?
10%
Malnutrition is suspected if:
10% unwanted weight loss in 3 months
Body mass <90% of ideal
BMI <18.5 kg/m2
What laboratory tests suggest malnutrition?
Low albumin, transferrin, lymphocytes, Zn, Mg, vitamins
What physical examination findings suggest malnutrition?
Decreased fat and muscle mass, skin/hair/nail symptoms, edema, bleeding tendencies
What might cause increase nutrient loss, especially w/ hospitalized patients?
Malabsorption, diarrhea, bleeding, nephrosis, fistula drainage, protein losing enteropathy
