Micronutrients Flashcards
What are vitamins?
Vitamins are organic substances, present in small amounts in natural
foodstuffs, which are essential to normal metabolism and lack of which cause deficiency diseases
What do vitamins differ in?
Solubility
What are the fat soluble vitamins?
Fat soluble vitamins: A, D, E and K (KADE)
What are the water soluble vitamins?
B vitamins (B1, B2, B3, B5, B6, B9, B12, biotin, choline), vitamin C
What do vitamins do in regards to enzyme activity? what other effects can they have within the body?
Many vitamins act as cofactors for enzyme activity, and some have effects such as being methyl donors, as well as gene translation and activation
What happens when minerals interact with each other?
Minerals may interact with each other, therefore the requirement for one mineral
may be impacted by the amounts of other minerals
- For example- divalent cation minerals may compete and decrease absorption of each
other (Zn2+; Ca2+; Mg2+ )
TRUE OR FALSE: Some minerals in excess can lead to adverse effects?
TRUE
What essential nutrients are required for normal red cell production?
- Iron
- Folate (Vitamin B9 )
- Pyridoxin (Vitamin B6)
- Cobalamin (B12)
What is Iron used for ?
Essential for hemoglobin
What is folate required for?
is required for nucleotide synthesis. Important for rapidly dividing
cells
What B vitamin is Folate?
B9
What B vitamin is Pyridoxin?
B6
What is Pyridoxin required for?
important for protein synthesis
What B vitamin is cobalamin?
B12
What is B12 important for?
important for nucleotide synthesis, contains cobalt
Anemia caused by B12 deficiency is called?
Macrocytic Anemia
Anemia caused by Iron deficiency is called?
Microcytic Anemia
Where can ruminants/ hindgut fermenters receive their cobalamin?
They can rely on their gastrointestinal microbiota for cobalamin if there is enough cobalt in diet.
What is an iron deficiency?
Iron deficiency can occur as a result of either low intake or increased losses
What can cause iron losses in the body?
Chronic blood loss
- Internal parasites
- External parasites
- Tumors, Ulcers.
What can cause Heinz Body anemia?
Garlic/ Onion Ingestion
What is Haem Iron?
Haem iron is from haemoglobin in meat and fish and is in the reduced ferrous form.
What occurs with Haem iron in the stomach?
Haem containing iron in Fe2+ form is hydrolyzed from protein ‘globin’ component
What occurs to Fe2+ as it enters the small intestines?
Fe2+ remains soluble as it is bound to proteins and absorbed through enterocytes.
What is non haem iron?
Non Haem Iron is from plants and is in the oxidized Fe3+ (ferric) form.
What occurs in the stomach with non haem iron?
Some of the Fe3+ is reduced to Fe2+ in acid conditions of the stomach
What occurs to non haem iron / Fe3+ in the small intestines?
Some Fe3+ forms insoluble complexes at high pH of small intestine, lowering absorption rates and increasing excretion.
Which is more absorbable. Haem or Non haem Iron?
Haem Iron is more absorbable ( Already in Ferrous form)
Where is Haem Iron from?
Meats and fish
What percentage of haem iron is absorbed?
Depending on the individuals iron stores 15-35% of haem iron is absorbed.
What is the absorption rate of non haem iron?
2-20%
What can increase absorption of non haem iron?
Vitamin C
Why would vitamin C increase absorption of haem iron?
acidic pH will cause the reduction of ferric (Fe3+) to ferrous (Fe2+) iron, which sees to be a requirement for the uptake of iron into mucosal cells.
Which has more bioavailability, Haem or non haem iron?
Haem iron
What is vitamin A important for?
Epithelial health
What form is Vitamin A found in?
Vitamin A is found in the form of retinol (retinoic
acid) and beta carotene (provitamin A)
Herbivores are very efficient at doing what (in regards to vitamin A)?
Herbivores are efficient in the transformation of beta
carotene to retinol
TRUE or FALSE: All species can cleave beta carotene?
Not all species can cleave beta carotene
Where is retinol stored?
Retinol is stored in the liver and kidneys
What are the important functions of vitamin A?
- Maintain normal epithelial function
- Maintain immune function
- Vision
Do carnivores easily convert Vitamin A? Why?
Carnivores have more trouble converting Vitamin A since they are eating herbivores who have already transferred it into Retinol
What clinical signs can you see in patients with vitamin A deficiencies?
can cause brittle nails/ skin, higher incidence of ulcers.
What can destroy carotenoids?
Storage heat or direct sunlight.