Lecture 2: Macronutrients Flashcards
What are the macronutrients?
Proteins
Carbs
Fats
What is the kcal per macronutrient?
Carbs/proteins are 4 kcal/gram
Fats are 9 kcal/gram
What is a carb?
Organic compound made of carbon and water in a 1:1 ratio.
What do carbs lack?
No fatty acids
No amino acids
Where are carbs the majority of matter?
Plant matter
Why do we like carbs?
Readily usable energy. It is the primary source.
What % of calories are made up of carbs in a typical diet?
40-70%
What are the major functions of carbs?
Fuel for metabolic processes (ESP CNS, RBCs, and renal medulla)
Prevent protein breakdown for energy
Enable fat metabolism/oxidation
Taste/dietary variety
Healthy gut (our gut flora needs the fiber to eat)
Help form important cellular structures
What are the simple carbs?
Monosaccharides: glucose, fructose, galactose.
Disaccharides: sucrose, lactose, maltose
What is found in every simple carb?
Glucose.
What are the complex carbs?
Polysaccharides: Starches, cellulose, glycogen, gums, pectins
What are the primary starches in a human diet?
Amylose and amylopectin
What is glycogen?
Storage for glucose in ANIMALS.
What are the two types of fiber?
Soluble fiber, which dissolves in water and makes a gel-like material
Insoluble fiber, which stays intact and increases stool bulk.
What is fiber?
A resistant starch that is not absorbed or digested.
What is the recommended fiber intake?
30-38g for males
21-25g for females
Why do carbs need to be broken down?
Our body can only absorb monosaccharides in the GI tract.
How are carbs brokwn down?
Amylase from the salivary glands and pancreas.
Where are monosaccharides absorbed and moved?
Absorbed in the SI.
Moved to the liver.
Why do monosaccharides end up at the liver for processing?
It can covert all monosaccharides to glucose.
It can convert excess glucose into glycogen to store.
It can covert excess glucose to TG/fats if glycogen is full.
Why are complex carbs better to eat?
Increased satiety due to the longer breakdown time.
What is the impact of fiber on blood sugar/energy?
None.
What is glycemic index?
Evaluates the 2-hour postprandial curve for BG values relative to a reference standard
What is glycemic load?
Similar to glycemic index, but it takes into account the standard serving size of the food.