Nutrition Flashcards
What should optimal nutrition provide enough nutrients for?
*Prevent deficiency
*Optimise body stores
*Optimise biochemical/physiological function
*Optimise a risk factor for some chronic disease
*Minimise incidence of a disease
What is the recommended amount of units for an adult?
14
How much folic acid should a pregnant lady have in the first trimester?
400ug OD
Can organic compounds be synthesised within the body?
No
What are the functions of Ca, Mg and P?
Structural - bones and teeth
What does iron do?
*Haemoglobin
*Myoglobin (Muscle)
*Cytochrome P450s
*Catalase
*Peroxidase
*Cell growth and differentiation
How is Vitamin B12 absorbed?
The stomach produces an intrinsic factor, for receptor mediated endocytosis in the terminal ileum.
How are fat soluble vitamins absorbed?
Carried in micelles and absorbed passively with end products of fat digestion - monoglyceryl
Why are calcium and Iron absorption tightly regulated?
As too much Ca/Fe can damage cells
Explain how Iron is absorbed from dietary intake?
1) A person eats 10mg of iron
2) 1mg of iron is absorbed into the gut epithelial cells
3) Plasma transferrin iron carries 3-4mg of Iron around
4) The bone marrow, RBC precursors –> Tissue iron –> Iron lost from the body (1mg)
5) Iron circulates in RBCs (2500mg)
6) Goes to the Spleen and reticulo endothelial macrophages
7) then back to the plasma
How much iron is within the Iron stores?
300-1000mg
What is Iron stored as?
*Ferritin
*Hemosiderin
-If not stored damages DNA
How is Iron absorption tightly regulated?
Through the transport of proteins involved in the absorption of iron in the lumen of the gut.
*Haem carrier protein 1 - Haem Iron
*Divalent metal transport - Non-Haem iron - Carry iron into the epithelial cells
-This allows iron to be absorbed into the cell
Which is then stored as ferritin or transported by ferapartan into the bleed stream bound to transferrin
Vitamin C in the same meal as Iron increases absorption, Why is this?
Vitamin C is an anti-oxidant which reduces Fe3+ to Fe2+
Ferric –> Haem Iron
What happens to a patient who is anaemic?
*Hypochromic (Pale)
*Microcytic RBC (Small RBC)