Learning outcomes To know the definition of vitamins and minerals To understand the function of vitamin and minerals in the body To know what are the main sources of vitamins in the diet To understand the effects of vitamin excess and deficiency in the diet ID: 801699
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Slide1
Micronutrients Chapter 1
Learning outcomes
To know the definition of vitamins and minerals
To understand the function of vitamin and minerals in the body
To know what are the main sources of vitamins in the diet
To understand the effects of vitamin excess and deficiency in the diet
The amount of vitamins needed for various life stages
Slide2What are Micronutrients?
Micronutrients are vitamins and minerals needed in the body in small amounts
We will be looking at Vitamins in this chapter – minerals afterwards.
The main vitamins we will be looking at are:
Fat soluble:
Vitamins A, D, E, K
Water Soluble:
Vitamin B1, B2, B3, B9, B12, C
Slide3Vitamins
What are they?
They are chemical substances found naturally in unprocessed foods both Animal and Plant
Why are they needed?
They help prevent disease
Each Vitamin is given a name and a letter to help differentiate them from each other
Fill in the table as we go along
Fat Soluble – vitamins that are found in foods containing Fat
Water Soluble - vitamins that are found in foods that are high in water content
Slide4Antioxidants
Our bodies are exposed to different chemical from the air, water, food and pollution everyday.
Some of these pick up oxygen in the body and become reactive “free radicals”
Free Radicals can cause damage to the cells in our bodies
This can lead to heart disease, inflammation and cancer
Antioxidants – help to prevent these free radicals so that they cannot damage our bodies
These are Vitamins A, C and E
These are one of the reasons that we are encouraged to eat many fruit and vegetables and prevent people from developing these conditions.
Slide5Fat Soluble Vitamin A
Chemical name/main
food sources
Function in the body
Effects of deficiency
Why does this happen?
Effects of excess (rare)
Retinol
Whole
milk, semi skimmed milk, cheddar cheese, egg yolk, oily fish, butter, vegetable fats
Beta Carotene (it is an Antioxidant)
Converted to retinol in the liver, dark green vegetables, orange, yellow and red fruit and vegetables, butternut squash and sweet potato Keeps skin healthyWhen light levels are low – enables us to see dim light – produces a substance called dim purple in the retina (eye)Helps children growthProduces Mucus for the mucus membranes in the body i.e. mouthStored in the liver – will only see effect of deficiency when this store has been usedDo not grow properlySkin and mucus membranes dryNight blindness – cannot see dim lightCan lead to total blindnessChildren need the right balance of all nutrientsMore susceptible to Bacteria and viruses if weak immune systemInsufficient visual purpleEyes tired and dryExcess stored in liver – will start to poison itPregnant women – excess can harm the babyCan damage the development of an unborn childCan be toxic
Slide6Fat Soluble – Vitamin D
Chemical name/main
food sources
Function in the body
Effects of deficiency
Why does this happen?
Effects of excess (rare)
Cholecalciferol
Reaction of sunlight on the skin which causes
vitamin
D to be made under the skinOily fish, meat, eggs, butter, fortified cereals, vegetable spreadsEnables calcium to be absorbed from the small intestine during digestionHelps calcium be deposited in bones and teethChildren: Weak bones and teethLegs bend under the weight of their body RICKETSAdults: Bones start to weaken and break easilyOsteomalaciaCannot support body correctly Calcium removed from other parts for its pruposes and if not replaced bones weakened Excess will lead to excess calcium absorbed – damaging kidneys and other organs especially in children
Slide7Fat Soluble - Vitamin E
Chemical name/main
food sources
Function in the body
Effects of deficiency
Why does this happen?
Effects of excess (rare)
Tocopherol
Mainly
in plant foods – soya, olive oil, nuts, seeds, vegetable fat spreads
It is an Antioxidant
Too rare--
Slide8Fat Soluble – Vitamin K
Chemical name/main
food sources
Function in the body
Effects of deficiency
Why does this happen?
Effects of excess (rare)
Phylloquinone
Plant and Animal foods especially green leafy
vegetables, green tea, cheese and liver
Part of the process that enables the blood to clot when the body has been injured thus preventing further blood lossSometimes occurs in new born babies and they are they are given a dose when they are bornBabies can sometimes lose blood internally during the birthing process-
Slide9Water Soluble – B1 Thiamin
Chemical name/main
food sources
Function in the body
Effects of deficiency
Why does this happen?
Effects of excess (rare)
Thiamin
Meat (especially
pork), milk, cheese, vegetables, fortified cereals, wholemeal bread, fresh and dried fruit
Enables energy to be released from carbohydrates in the body during respiration
Beri Beri – where nerves and muscles affected and there are problems with memory, concentration and heart rateEnergy is needed by the nerve cells – controls how the brain works – deficiency will not enable them to work correctly-
Slide10Water Soluble – Vitamin B2 Riboflavin
Chemical name/main
food sources
Function in the body
Effects of deficiency
Why does this happen?
Effects of excess (rare)
Riboflavin
Found in many
foods – milk, milk products, eggs, fortified cereals, rice and mushrooms
Enables energy to be released from carbohydrates in the body during respiration
Rare – Sores in the corner of the mouth as needed to help maintain healthy skin--
Slide11Water Soluble – Vitamin B3 Niacin
Chemical name/main
food sources
Function in the body
Effects of deficiency
Why does this happen?
Effects of excess (rare)
Niacin
Beef,
pork, wheat flour, eggs, milk (Cow)
Can be made from an amino acid called Tryptophan in the body
Enables energy to be released from carbohydrates in the body during respirationPellagra: Symptoms – diarrhoea, dermatitis (sore, dry, cracked skin), Dementia (loss of memory, confusion, cannot speak properly)Prevents the brain and nervous system from working properly
Slide12Water Soluble – Vitamin B9 Folate (Folic Acid)
Chemical name/main
food sources
Function in the body
Effects of deficiency
Why does this happen?
Effects of excess (rare)
Folate – called folic acid when
used in supplements
Not found in many foods naturally
Best sources are green leafy vegetables, yeast extract such as marmite, peas, chickpeas, wholegrain rice, bananas, oranges
Works with vitamin B12 to make healthy red blood cellsHelps reduce the risk of central nervous system defects i.e. Spina Bifida in unborn babiesCan lead to anaemia - megaloblastic (large cells) where they become enlargedSpinal cord defects in unborn babiesRed blood cells do not grow to the right size and grow very bigPrevents them from passing through the blood vessels (capillaries)
Slide13Water Soluble – Vitamin B12 Cobalamin
Chemical name/main
food sources
Function in the body
Effects of deficiency
Why does this happen?
Effects of excess (rare)
Cobalamin
Does
not occur naturally in food.
Found in liver, meat, fish, cheese, fortified cereals
Works with folate to make healthy red blood cellsKeeps nerve cells healthyCan be stored in the liver for 2 or more yearsVegans need to ensure that they take B12 supplements to avoid a deficiencyCan lead to a type of anaemia Pernicious AnaemiaAbsorbed in the small intestine – can only do this if special cells in the stomach that produce protein are not damaged-
Slide14Water Soluble – Vitamin C Ascorbic Acid
Chemical name/main
food sources
Function in the body
Effects of deficiency
Why does this happen?
Effects of excess (rare)
Ascorbic
Acid
Mainly fruits and vegetables especially citrus fruits, kiwi, blackcurrants, cabbage, Brussel sprouts, broccoli
Helps
the body to absorb the mineral iron in the small intestineNeeded to maintain connective tissue which holds the body cells together in the skin, blood vessels, musclesAn important antioxidantSome can be stored in the body for monthsIron is not absorbed which leads to iron deficiency anaemiaBleeding from small blood vessels under the skin and in the gums leads to red spots under the skin and loosing teethCan lead to Scurvy and deathIron is needed to make haemoglobin in the red blood cellsConnective tissue starts to break down – allows the blood to leak out and weakens the tissue in the gums that holds the teeth in placeConnective tissue cannot be made properly to heal a wound – starts to break down which can open scars
Slide15Amount of Vitamins needed everyday for different life stages
Slide16Questions