Water soluble vitamins Flashcards
What are things that could potentially cause damage to vitamins?
Light
Oxidation
Cooking
Storage
How is absorption of water and fat soluble vitamins different?
Water soluble vitamins are absorbed into bloodstream and are excreted in urine.
Fat soluble vitamins are absorbed into lymph then blood. In blood they are carried by protein carriers and stored in cells that typically store fat.
What is a big risk factor for fat-soluble vitamin toxicity?
Fat-soluble vitamins are likely to reach toxic levels with
supplement use
What is the Estimated Average Requirement and how is this taken into account when deciding an RDI?
Different people have different requirements for certain nutrients. EAR takes into account 50% of the population.
RDI is set at a value well above the EAR and as a result covers 98% of the population.
What is bioavailability?
Bioavailability is the rate and extent that a nutrient
is absorbed and used
What other forms can vitamins be consumed in?
Precursors (provitamins) are
consumed in an inactive form and become active
vitamins in the body
What is the function of thiamin (Vitamin B1)?
Thiamin is involved in energy metabolism as part of
the coenzyme thiamin pyrophosphate (TPP)?
What is the RDI of thiamin?
Men: 1.2mg/day
Women:1.1mg/day
What are the symptoms of thiamin deficiency?
Enlarged heart and possible cardiac failure
Muscular weakness
Apathy, poor short-term memory, confusion, and
irritability
Anorexia and weight loss
What deficiency causes Wernicke-Korsakoff syndrome?
Thiamin deficiency (caused by alcohol abuse)
What are the effects of alcohol consumption on thiamin?
Alcohol decreases absorption and increases excretion of vitamin B1.
Which vitamin deficiency causes the disease beriberi?
Thiamin
What is the difference between dry and wet beriberi?
Wet beriberi reflects damage to the cardiovascular
systems and presents with oedema (accumulation of vasodilators)
Dry beriberi reflects damage to the nervous system and
presents with muscle wasting
How common is the incidence of thiamin toxicity?
There are no reported toxicities
What are some food sources of vitamin B1?
Wholegrain, fortified or enriched grain products
Moderate amounts in all foods ( I remember this using its function; thiamine is involved in TPP function which is a step shared by all living creatures. We eat other living things so we get some vitamin B1 from other things.)
Yeast spreads (Vegemite)
Pork, my favourite yum
How does thiamin respond to cooking?
Vitamin is destroyed by heat so it needs to be steamed or microwaved.
What is the function of riboflavin?
Riboflavin is involved in energy metabolism
Flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD) are the reducing equivalent coenzyme forms
What is the RDI of riboflavin?
Men: 1.3mg/day
Women: 1.1mg/day
What are the symptoms of riboflavin deficiency? What is the name of the condition?
‘A’riboflavinosis:
Inflammation of the membranes of the mouth, skin, eye
and GI tract.
Sore throat and cracks and redness at corner of mouth.
Skin lesions covered with greasy scales.
Painful, smooth, and purplish red tongue
How common is the incidence of riboflavin toxicity?
No reported toxicities
What are some sources of vitamin B2?
Milk products; including yoghurt and cheese.
Enriched and whole grains.
Liver
Is vitamin B2 destroyed by cooking?
No
What destroys vitamin B2?
ultraviolet light.
What is the function of niacin (vitamin B3)?
Glucose, lipid, fat, and alcohol metabolism (NAD+ coenzyme)
What is the RDI of niacin?
Since body can obtain niacin from dietary tryptophan the RDI is in niacin equivalents (NE);
60mg trp = 1mg niacin
In men: 16NE/day
In women: 14NE/day
What is the upper intake level of niacin?
35mg/day
How can niacin be destroyed or lost?
It can be lost into water
What other functions does Niacin have?
It can transport electrons to pyruvate during anaerobic respiration (lactate production)
What are the deficiencies associated with niacin?
diarrhoea, abdominal pain, and vomiting
inflamed, swollen, smooth and bright red tongue
depression, apathy, fatigue, loss of memory, and
headache
Rash when exposed to sunlight
the four Ds: Diarrhea Dermatitis Dementia Death
Deficiency in what vitamin results in pellagra?
Vitamin B3 (NIacin)
What are the symptoms of niacin toxicity?
Niacin flush (painful tingling sensation results from dilated capillaries)
painful flush, hives and rash
excessive sweating
blurred vision
liver damage
impaired glucose tolerance
What are some niacin sources?
Milk
Eggs, meat, poultry, fish
whole-grain and enriched breads and cereals
nuts and all protein-containing foods
How can niacin bioavailability in food be improved?
Treating food with alkaline
What is the function of pantothenic acid?
Pantothenic acid is involved in energy metabolism
as a part of coenzyme A