HNF 150 EXAM 2 VITAMINS ONLY (EXAM REVIEW SOLUTION 2024)

HNF 150 EXAM 2 VITAMINS ONLY (EXAM REVIEW SOLUTION 2024) List the fat soluble and water soluble vitamins, and compare and contrast how the solubility affects the absorption, transport, storage, toxicity, and excretion of each type. Know generalities for fat versus water soluble vitamins, not specifics for each vitamin. - CORRECT ANS-1. *Fat Soluble*: Vitamin A, D, E, K Need more periodically Found in fats and oils of foods - require *bile* for absorption -*More likely to be toxic than water soluble ones* ; toxicity usually from high-dose supplements, rarely from food (exception: *K* is rarely toxic, but if we eat too much we can get very sick and die) -Digestion similar to dietary fat - Bile and pancreatic enzymes, Absorbed in micelles in SI, *Packed for transport through lymphatic system*, *Carried by chylomicrons and other blood lipoproteins to liver where repackaged for release into blood in the liver* -*Stored in liver & adipose tissues - so not much is excreted* 2. *Water Soluble*: B Vitamins, Vitamin C, and Choline *Need in excessive amounts* -Digestion & Absorption: --*Digestion*: cleave from protein in stomach --*Travel* through the body on their own freely through watery body fluids --*Absorbed* from small intestine to blood -Storage in body tissues is minimal (Except B12 & B6) - so more is excreted -Seldom reach toxic levels (except B6) -- *excess is excreted in the urine (except b12 and b6)* Recall how vitamin recommendations are determined. - CORRECT ANS-Balance studies; how much comes in and how much goes out (variation in people) based on healthy people RDAs are set where 98% of population meets requirements Main Functions/Roles of *Vitamin D* in the body - CORRECT ANS--*Calcium absorption and regulation in blood, Phosphorus regulation, Bone Metabolism assistance (& teeth)* -Vit D is a *steroid hormone* that regulates blood calcium and phosphorus levels, and bone metabolism -*Adequate calcium and phosphorus are needed for vitamin D to have positive effects on bones* -Active Vitamin D *raises blood levels* by: --Increasing calcium and phosphorus absorption from small intestine **Need Vit D3 to absorb the Ca we eat --Telling kidney to retain calcium and decrease excretion --Mobilizing calcium and phosphorus from the bone (bone turnover, bone resorption)...