Micronutrients Flashcards
Why are vitamins and minerals useful?
Vitamins, minerals and trace elements are fundamental groups of nutrients to sustain life
They have a physiological role at the cellular level
How do vitamins work?
Vitamins often acting as co-enzymes in metabolic pathways
How do minerals and trace elements work?
Minerals and trace elements participate in wide ranging cellular mechanisms
What are processed foods considered to be?
Energy dense and micronutrient light
In which food groups are the micronutrients found?
All of them
Why are foods fortified?
To manage population deficiency
Who are we concerned about regarding micronutrient deficiency?
Generally population is well nourished BUT…
Concerns about marginalised groups, minority groups, the very young and the very old are associated with
-Poor dietary intake
-Excessive energy dense/nutrient light diets
-Extreme diets (removal of one or more food groups)
What evidence is there of a micronutrient deficiency in the UK?
There is evidence of iron-deficiency anaemia (as indicated by low haemoglobin levels) and low iron stores (plasma ferritin) in a proportion of adult women and older girls. This is in line with findings from previous surveys and does have health implications for these groups.
There is evidence of low vitamin D status in adults and older children, both male and female. This has implications for bone health, in particular increased risk of rickets and osteomalacia.
A substantial proportion of adults and older children have functional riboflavin (B2) status values indicative of low status. However the health implications of this are not known.
There is no evidence, at a population level, of low status for other micronutrients where normal ranges or thresholds for low status have been set. Levels of vitamin C, B6, B12, thiamin, retinol and vitamin E fell within the normal range.
What micronutrient deficiency is most closely associated with alcohol liver disease?
Thiamine (B1)
Vitamin D,
What micronutrient deficiency is most closely associated with Inflammatory bowel disease?
iron, B12, vitamin D, vitamin K, folic acid, selenium, zinc, vitamin B6, and vitamin B1
What micronutrient deficiency is most closely associated with Obesity?
Vitamin D
Copper
Zinc
Where is the most common source of vitamin C?
Foods of plant origin
Where is the site of vitamin C absorption?
Buccal mucosa
Stomach
Small Intestine
Describe the mechanism of absorption of vitamin C
Buccal – passive diffusion
Gastrointestinal absorption is rapid and through carrier-mediated transport system
if mucosal concentration less than 6mmol/L
What is the relationship between quantity and absorption of vitamin C?
<20mg ingested – 98% absorbed
>100mg ingested 6% absorbed
What does vitamin C accelerate the absorption of?
Iron
Where is vitamin B1 found?
In most food
Where is vitamin B1 absorbed?
Jejunum and ileum
Describe the mechanism of absorption of B1
At low concentrations by active Na+ dependent processes
At high concentration (>8mg in single dose) passive diffusion
What is the name of a deficiency of B1?
Wernicke Korsakoff syndrome
Where is vitamin B2 (riboflavin) found?
In most food as a coenzyme
How is B2 absorbed?
Small intestine
How is vitamin B2 absorbed?
2 stage process released from proteins - proteolytic enzymes and then hydrolysed by brush border enzymes
Where is vitamin B12 found?
Synthesised by micro oganisms – in animals but not plants. Concentrated through food chain
On plants – contamination by soil bacteria
