07 Minerals Flashcards
What are the two forms of iron found in the human body, and what are the two forms of dietary iron and where are they found?
Ferric (Fe3+) and Ferrous (Fe2+).
Haem iron - flesh foods.
Non-haem - flash and plant foods.
What groups of people are usually recommended iron sups by doctors?
What are the most absorbable forms of supps and when best taken?
Pregnant women, infants and small children.
Iron sulphate and chelate, taken between meals or on empty stomach, not with milk, tea or coffee which impairs absorption.
Where does hame and non-harm iron fall in dietary iron levels and how much is absorbed?
Haem - 10% dietary and 25% absorbed.
Non-Haem - 90% dietary but only 17% absorbed.
How is iron absorbed in the gut and which vitamin increases absorption?
A protein called mucosal-ferritin stores in mucosal cells in the small intestine.
When needed, mucosal transferrin transfers it to blood transferrin which transports it to the rest of the body.
What can inhibit iron absorption?
Phytates, oxalates, polyphenols, calcium, tannic acid in tea, soy protein and eggs.
Where is iron mostly transported to and where and how is surplus iron stored after this?
Mostly transported to bone marrow to make RBC’s.
Excess is stored in the protein ferritin in the liver, marrow and spleen.
What 5 places is iron present in the body and explain each?
Haemoglobin - for oxygen transport.
Myoglobin - for oxygen storage in muscle.
Catalase and peroxidase - enzyme that protect against ROS
Cytochromes - enzymes for energy prod in electron transport chain.
What is the difference between iron def and iron def anaemia?
Iron def is depletion of iron in body stores.
Iron def anaemia is severe depletion that results in low haemoglobin concentration.
How does low iron levels cause iron def anaemia and what are SS?
Results in small pale RBC’s that cannot carry enough oxygen to tissues - energy metabolism then falters.
SS - fatigue, weakness, headaches, apathy poor resistance to cold temps, pale skin.
What iron rich foods are best eaten for veggies/vegans?
What to avoid?
Whole grains
Tofu
Green vegetables
Pulses
Yeasted, sprouted, roasted and fermented foods.
Avoid black tea or wheat bran with iron rich foods.
What are common vegetarian mistakes when missing iron?
Easting non-meat western diet full of processed foods.
Eating too much cheese and dairy for protein, which can impair absorption.
Drinking black tea with meals.
What are 4 vulnerable stages of life where iron loss plays a part and why?
Women at reproductive age - periods/loss of blood.
Pregnancy - extra iron needed for increased blood volume and blood loss at child birth.
Infants/toddlers - high milk diets and little iron
Teenagers - due to rapid growth
How can iron overload occur?
Overuse of iron supps.
Genetic defects.
High dose vit C supps enhancing iron absorption.
Repeat blood transfusions.
What can iron overload result in (5 things)?
Tissue damage - esp liver. Infections - bacteria love iron rich blood. Increased risk of insulin resistance. Oxidation of LDL. Creation of carcinogens.
How does Haem iron react with nitrates in processed meat and foods and does non-harm have the same effect?
Haem iron catalyses formations of carcinogens from the nitrates in the food.
Non-Haem does not do this.
