Dietary Carbohydrates Flashcards
what is the rough estimate for energy expenditure (EE)
EE= 25 - 35kcal/kg per day
describe how to calculate the number of grams of carbohydrate consumed per day by an individual in energy balance
(calories needed per day X [%]carbohydrate intake)/4
How is Fructose metabolized differently than glucose.
1) it enters cells through a general hexose transporter and so its entrance is not regulated by insulin.
2) does not stimulate insulin release.
3) bypasses the key regulated step of PFK.
what is amylose?
Amylose is a long unbranched chain of glucose molecules. As a result, there are only 2 “free ends” that can be subjected to digestion by amylase. This form of carbohydrate is a slowly digested and absorbed.
What is Amylopectin?
Amylopectin is a highly branched form of starch. As a result, the intestinal amylase has many “free ends” of the polymer to digest and as a result the digestion and absorption is rapid.
what is Resistant starch:
example: corn starch. Because of its crystal structure it is slowly absorbed.used in children with inborn errors of metabolism that predispose them to hypoglycemia due to problems with hepatic glucose production during fasting.
what is fiber
Fiber is a form of complex carbohydrate that is not digestible by human intestinal enzymes. As a result, these forms of carbohydrate pass through the GI tract largely unaltered
what is the clinical presentaion of classical galactosemia
vomitting, diarrhea and jaundice
what does galactokinase deficiency cause?
elevation of galactose in blood (galactosemia) and urine (galactosuria)
accumulation of galactose 1-phosphate due to galactokinase deficiency can result in _______
liver damage,
severe mental retardation
cataracts
what are the adverse health effects from fructose metabolism
insulin resistance and hypertriglyceridemia.
