Lecture 25 Flashcards
What is the nz diet state for minerals? What does mineral deficiency in children mean?
Mineral deficiency in children can lead to growth problems. The NZ diet is adequate for sodium, potassium and chloride, it is maybe adequate for phosphorus and magnesium (seems fine but neither are particularly measured) and is not adequate for calcium. High potassium is typically a good indicator of a good diet while an overly large amount of sodium (or chloride) is a general indication of lots of processed food.
What is the NZ diet state for trace elements? What were examples done to fix this?
The NZ diet is adequate for iron, zinc, iodine and fluoride it seems adequate for copper, manganese and molybdeum it is insufficient for selenium. (Trace elements). Iodised table salt added iodine into our diet, fluoridated water added fluoride to the water. Selenium is in Australian flour and is used to make bread, a staple in many diets.
What do minerals act as and what are some examples of roles?
Minerals act as: cofactors, structural role (e.g calcium and phosporous in hydroxyapatite crystals in bone), key constituent of molecules, tranfer of electrons, nerve impulse and muscle contraction and fluid and electrolyte balance. All minerals have multiple roles in the body (e.g phosphorous for bones and teeth and acid-base balance, magnesium in bone/teeth and muscle contraction, sodium and potassium in nerve and muscle, sulfate in parts of proteins and insulin).
What are some roles of trace elements?
All trace elements have multiple roles except for molybdenum (cofactor for enzymes), iodine (thyroid hormones), fluoride (dental caries).
What does magnesium do? What does deficency lead to?
Magnesium is the Magnesium is the cofactor for over 300 enzymes which do many processes, it stabilises proteins, nucleic acids and membranes, it’s an electrolyte, is involved in nerve and muscle action and also bone remodelling. There are no overt symptoms of magnesium deficiency, however there is evidence that it can help with muscle cramps via the Cochrane collaboration, this uses systematic review and meta-analysis and typically involves randomised control trials, it showed no effect of magnesium in helping muscle cramps.
What is selenium? How was its deficiency effects found and what are they?
selenium is an antioxidant which works with vitamin E and is also involved in other enzymes. Studies were done to analyse deficiency via prospective cohort studies (large group of people, following them to associate diet and disease, this is subject to bias however). Deficiency is quite low in pasture-fed animals, they develop white muscle disease due to the low NZ soil selenium levels. Humans will develop cardiomyopathy and therefore Keshan’s disease (only really in China, no problems in New Zealand). Though low selenium could also possibly be linked to cancer, but no real link was found.
