Transcript Document 7172145

NUTRITION
Nutrition is the study of nutrients
in food and how the body uses
them
Nutrients
5 Nutrients found in food
• Protein
• Vitamins
• Minerals
• Carbohydrates
• Fats/Lipids
Also found in food and needed by the body
• Water – is classed as a nutrient by some
• Fiber
PROTEIN
The word protein is from the Greek meaning
“ I am first”
What is Protein?
• Proteins are chemical compounds found in
every body cell.
• They are made up of small units called
amino acids – these are considered the
building blocks of Proteins.
• There are 20 important amino acids
required by humans.
Essential Amino Acids
• 9 are called essential amino acids
because the body cannot make them fast
enough or not at all.
• phenylalanine, valine, threonine,
tryptophan, isoleucine, methionine,
leucine, and lysine.
11 Non-essential Amino Acids for
Adults
• Some are generally classed as
nonessential amino acids except can be
considered essential for infants and
growing children- cysteine , tyrosine,
histidine and arginine.
• Some nonessential amino acids can be
made by the body -Alanine, Asparagine,
Aspartic Acid, Glutamic Acid, Glutamine,
Glycine, Proline, Serine.
Why Protein?
• Needed for growth, muscle building, and
repair of tissue.
• Supply energy when needed
• Help make antibodies, enzymes,
hormones, and some vitamins
• Regulates fluid balance in cells and other
body processes.
Where found?
• Complete proteins (or animal protein)
Contain all 9 essential amino acids
• found in animal protein such as meat, fish,
eggs, milk, and cheese and soybean.
• Incomplete proteins or vegetable protein
missing 1 or more essential amino acids
• found mostly in vegetable like beans,
peas, lentils, legumes, nuts.
Some Amino Acids
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Names & use of some amino acids
Names of some essential amino acid
Tryptophan – relaxant, helps sleep
Lysine – absorption calcium
Methionine – supplies sulphur for hair, nails
Leucine – alertness
Phenylalanine – nerve cell to brains signals,
awake & alertness, improve memory
• Valine – coordination, calmness
Kwashiorker
Problems
• Too little – Protein-energy-malnutrition
(PEM) -can cause fatigue, poor growth
and tissue repair.
• Kwashiorkor – protein deficiency
disease- large protuberant belly as seen in
famine stricken places.
• Too much – converted to fat and stored
causing weight gain.
Vegetarians
• Vegan – eat no animals or products
• Diet lacks in essential amino acids without
tofu or a variety of foods eg lentils,
legumes
• Lacto – vegetarian – do not eat meat or
fish but will eat some animal products
VITAMINS
• Generally help the immune system, help
make some nutrients, and help some
nutrients to be absorbed and used by the
body.
• Needed in small amounts for growth, avoid
diseases, & maintenance.
• Body cannot produce most vitamins
Vitamins
• Fat-soluble vitamins – dissolve in fat and
carried by fats in food. Can be stored
• Water-soluble vitamins – dissolve in
water. Cannot be stored
• Named after some letters of the alphabet
Vitamin A
Why? - To make a compound needed to help
eyes adapt to darkness; promote growth of teeth
and bones, and healthy skin.
Where?- Found as Beta-carotene which converts
to vitamin A in the body -- found in orange, deep
yellow, red, dark green colored food like carrots,
oranges. mainly in fruits & vegetables, liver,
eggs, whole milk,& its products, oily fish, & fish
oils.
Fortified foods like margarine, & juices.
Vitamin A
What about deficiency? - eyes become
sensitive to light, night blindness, poor skin
stunted growth.
What about excess? - since it can be
stored too much can be toxic.
Can cause fatigue, headaches, nausea,
vomiting and extreme case death.
VITAMIN B
This is a group of vitamins belonging in
the B-complex
Vitamins such as Thiamin – B1,
Riboflavin B2, Niacin, B6, Folate, and
B12,
They are water soluble and have
distinct properties
THIAMIN B1
• Why? - Helps body breakdown
carbohydrates and release energy.
• Helps promote normal appetite, digestive
system and nervous system.
• Where? - Most foods. Good sources are
wheat germ, whole grain, lentils, beans,
cereal, meat,particularly pork.
VITAMIN B1
• What - about deficiency? Loss of
appetite, low energy, nausea
• Severe lack can lead to disease of
nervous system called Beriberi –
numbness of feet, cramps in leg, paralysis
& heart attack - death.
RIBOFLAVIN B2
• Why ? – breaks down carbohydrates,
helps skin, tongue, lips & prevent greasy
areas around mouth and nose.
• Where ?– Offal - organ meats e.g. liver,
kidneys, milk & products, green
vegetables, whole grains & cereals
• What about deficiencies? – swollen
cracked lips, skin lesions, twilight
blindness.
Niacin B3
• Why ?- Helps the cells use other nutrients
& keep nervous system mouth, skin &
digestive tract healthy.
• Where ?- meat, poultry, milk, peanuts
• Tryptophan (amino acid) converts to niacin
– milk has tryptophan.
• What? – disease called Pellagra – skin
lesions, digestion, mental disorder &
death.
Vitamin B6
• Why? – helps regenerate red blood cells
& breakdown of carbohydrates for energy.
• Where? – most vegetables, meats, liver,
whole grain cereal.
• What about deficiencies? – Skin lesions,
sore mouth, red tongue, nausea, weight
loss & convulsive seizures.
Folate ( B9)
Why? – produces blood cells, converts food to
energy, helps prevents damage to brain & spinal
cord of unborn babies. Helps immune system
Where? – green vegetables, dry beans, peas,
liver, most fruit, yogurt & whole grains.
What about deficiencies? – inflamed tongue,&
diarrhea. Fatigue,& weakness caused by
anemia – low in red blood cells.
Pre – pregnant or pregnant women asked to take
supplements. Also people with low immune
system.
Vitamin B12
Why? – promotes normal growth. Helps cell
function in bone marrow.
Where? – animal protein foods, brewer’s
yeast & fortified cereals.
What about deficiencies? – fatigue, loss of
weight, nervous disorders, extreme case –
pernicious anemia – abnormally large
red blood cells.
VITAMIN C
• Why? – Healthy skin, gums & tissues,
heals wounds, broken bones, fights
infection, helps hold body cells together.
• Where? – citrus fruits, other fruits - kiwi
fruit, berries, red peppers, green
vegetables, potatoes, tomatoes.
• What about deficiencies? – water
soluble – need daily, prevents skin disease
-scurvy
VITAMIN D
• Why? – helps formations of bones & teeth with
calcium & phosphorus.
• Sunlight UV rays help ergosterol in fat
underneath skin convert to vit. D
• Where? – animal fats & fish liver oils, oily fish,
eggs, milk and products, fortified foods e.g.
juices,margarine
• What about deficiencies? - disease called
rickets – deformed bones e.g. bow legs; dental
decay.
• Supplement diet if spending life mostly indoors
and during long winters.
MINERALS
• Inorganic substances that make up 4% of body
weight. Become part bones, soft tissues & body
fluids. Regulate body processes.
• Macrominerals – large amount 100mg or more
needed per day – calcium, phosphorus,
magnesium, sodium, potassium.
• Microminerals – small amounts needed - less
than 100mg per day – iron, zinc, iodine, fluorine.
CALCIUM
• Why – needed to build strong bones and
teeth. Helps blood clots and nerves.
Stored in bones important to eat plenty
during growing years or if pregnant. Helps
reduce cramps during menstruation or
over exercise, and sometimes pms
Where – milk and products, eggs, green
vegetables, whole fish, fortified foods e.g.
cereals & juices
Calcium
What about deficiencies – Hard to absorb
– need magnesium to help. Absorption
easier during growing years as bones are
soft - can be stored for later years.
Children can get malformed bones. Body
takes from bones causing them to become
weak, porous & brittle – osteoporosis in
old people mainly women and some form
of arthritis.
PHOSPHERUS
• Why? - works with calcium and excess
stored in bones. Helps release energy,
balance acids/alkalis in blood.
• Where? – meat, fish eggs, milk &
products, soft drinks.
• What about deficiencies? – not much but
calcium will be pulled to make up - can
lead to osteoporosis.
MAGNESIUM
• Why?- mostly in bones, helps proteins, fats &
carbs produce energy. Helps body absorb
calcium
• Where? – whole grains, nuts, seeds, beans,
vegetables.
• What about deficiencies? – usually healthy
people following varied diet get enough. Can
cause muscle twitching, insomnia, muscle
tremors if insufficient.
• Osteoporosis & arthritis due to poor absorption
of Calcium
ZINC
• Why? – helps immune system, breakdown
proteins, cell reproduction, healing wounds and
fertility & conception.
• Where? – meat esp. poultry, dairy products,
beans, whole grains - cereals, nuts
• What about deficiencies? – body only absorbs
30% of zinc consumed therefore zinc deficiency
common. Magnesium, Phosphorus, & Calcium
help absorption– sleep disturbances, dandruff,
delay wound healing, diarrhea, loss of appetite,
poor nail growth - lines, white spots on nails
Sodium, Chlorine,Potassium
• Why – work as team like Ca, P & Mg.
Control osmosis – fluids flow from cells for
balance, helps cells absorb nutrients.
• General deficiency –losing these salts
can affect blood pressure – weakness,
fainting, dizziness. increase intake if
diarrhea/vomiting, (bulimia), heavy
exercise & perspiration
• Potassium – helps lowers blood pressure,
muscle twitching, regulates heart rate
spinach, fennel, cantaloupe, bananas,
mushrooms, lentils, nuts, green
vegetables & fruits
• What about deficiency? Higher blood
pressure – increase chance of stroke,
muscle spasms, cramps.
• What about excess? Blood pressure too
low – dizziness, light headed and fainting,
low heart beat.
SODIUM / CHLORINE
• Why? – regulate blood pressure
• Where? –table salt, (Sodium Chloride), leafy
green vegetables, & animal products, salt water
fish, processed foods, deli meats, soy sauce,
cereals, preserved food, and restaurant food.
• What about deficiency? – increase intake if
diarrhea/vomiting, (bulimia), perspiration loses
sodium.
• What about excess? Excess – causes
hypertension - high blood pressure can lead to
serious heart/kidney problems & cause stroke.
Known as the silent killer. Limit use of table salt
and processed foods and restaurant food.
IRON
• Why? – combines with protein to form
hemoglobin. Stores in body.
• Where? – offal ( internal organs ) e.g.
liver. Egg yolk, meat, dark green
vegetables, grain products, fortified
cereals, iron cooking pots.
• What about deficiencies? can be hard to
absorb – Vitamin C helps absorption –
Anemia (common in females), loss of
appetite, tiredness, pale skin.
IODINE
• Why? – helps hormone thyroxin in thyroid
glands function properly & regulate rate of
energy used.
• Where? – table salt, saltwater fish &
shellfish,
• What about deficiencies? – cells in gland
enlarge & form lump in neck called goiter,
poor growth and energy
FLOURINE
• FLOURINE
• Why? – helps prevent tooth decay,
maintains bone health.
• Where? – city drinking water, toothpaste.
• What about deficiencies? – can cause
tooth decay/cavity.
CARBOHYDRATES
3 groups of carbohydrates:
1. Sugars – simple carbohydrate
2. Starches – complex carbohydrate
3. Fibers – complex carbohydrate
Nearly all carbs. absorbed by the body as
monosaccharides or single sugar units
Functions of Carbohydrates
• Provide energy, help body digest fats,
allows protein to be used for growth &
maintenance.
• Deficiency – protein is used for energy,
causing chemical imbalance.
• Excess – deprivation of other nutrients,
eroded teeth, gum disease, converted to
fat & stored causing obesity.
CALORIES
Excess- Food energy is measured in
calories. It takes 1 calorie to produce
energy to heat 1 gram of water 1 degree
C. If more carbohydrates are eaten than
calories burned remainder is converted to
glycogen and fatty tissue - stored by the
body - obesity
• Proteins have 4 calories per gram
• Carbohydrates have 4 calories per gram
• Fats have 9 calories per gram. Fat calories
convert to fat faster in body and stored
• Vitamins and minerals have no calories
SUGARS – simple carbs
Where? – sugar, fruit, sugar products,
syrups, soft drinks, jams, candies and
sweet desserts.
SUGARS
• Called simple carbohydrates - easy break down
and absorb into blood. Simple bond structure
• 6 types of sugars found naturally in food.
• 1 unit sugars
• Glucose – carried in this form in the bloodknown as “ blood sugar”
• Fructose – found in fruit known as “fruit sugar”.
• Galactose – found attached to glucose in milk
SUGARS
Pairs of sugar units
1. Sucrose – ordinary table sugar from
sugar cane or sugar beet.
2. Lactose – “milk sugar”- milk from
mammals.
3. Maltose – in grain products - flour “ malt
sugar”
STARCHES
Complex carbohydrate – made from many
glucose units bonded together. Starch
breaks down into simple form during
digestion to form glucose.
Why? – for energy
Where? - Starch is storage form of energy
in plants. Found in potatoes, flour
products, rice, cereal, grains.
Excess – glucose is converted to fat and
stored
FIBER
Complex carbohydrate
• Where? – fruits, vegetables, whole grain
cereal, foods that cannot be digested.
• Why? - Provides bulk in diet, promotes
bowel function, linked to prevent heart
disease, lower cholesterol, dilutes
carcinogens – reduces risk of cancer.
• Deficiency – constipation can occur.
FATS
• Why? Provide protection, body temp &
energy
• Belong to a group of compounds called
Lipids which includes fats & oils.
• Lipids are fatty acids that are chains
containing carbon, hydrogen & oxygen
atoms.
• Amounts of hydrogen atoms vary in Fatty
acids.
Saturated fatty acids
• 1.Saturated – have as many hydrogen
atoms as it can hold – full,
• Present in meats and dairy , palm &
coconut oil.
• Tend to be solid at room temperature.
Bonds packed together closely
Unsaturated Fatty Acids
• 2.Unsaturated- fewer hydrogen than they
can hold. Double bonds therefore not as
packed together – usually liquid
• a. Monounsaturated – missing 1 H atom
• b. Polyunsaturated – 2 or more H atoms
• Body absorbs fats as fatty acids & glycerol
HYDROGENATION
• Hydrogenation – adds H to Fatty acids in
oil – turns liquid oil to solid saturated fats.
Vegetable shortening & margarine made
from hydrogenated oils.
• Trans fatty acids – partly hydrogenated
oils. Result in odd molecular shape which
can cause health concerns in body.
• Being banned in some States.
Function of Fats
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Why? Provide energy
Carry some vitamins e.g. A
Help make hormones.
Protect organs
Maintain body temperature
Not all fatty acids made by body –
essential fatty acid only obtained from
foods you eat.
Sources of Fats
• Visible fats – butter, margarine, fat on
meat, skin.
• Invisible – eggs, cream, salad dressing,
mayonnaise, nuts, avocados.
Deficiency – not common – infants may be
deprived by over concerned parents.
Excess – Fats have more calories – unused
stored cause obesity.
CHOLESTRAL
• Waxy fat like substance found every cell
• Helps transport fatty acids and produce
hormones
• Dietary cholesterol consumed from
animal products. None in vegetables.
• Blood cholesterol – in bloodstream – can
lead to heart problems. Body makes
cholesterol it needs no need to consume
Fats and Cholesterol
• Saturated and dietary cholesterol can
increase blood cholesterol – heart disease
• Trans fats also raise blood cholesterol
• Unsaturated fats help reduce cholesterol.
• High fat linked to increased risk of some
cancers.
• Eat sparingly, limit eating foods fried in
trans fats.
BMI Body Mass Index
• BMI = weight in kg divided by height in meters
squared – 50 kg______
•
1.52 x 1.52
• BMI = weight in pounds divided by height in
inches squared x 703 120___ x 703
•
63 x 63
• 18.5 or less = low BMI – underweight
• 18.5 – 24.9 = medium BMI - normal
• 25 – 29.9 = high BMI – overweight
• 30 and above = very high - obese
Metabolism
• Chemical process takes place in cells after
body absorbs nutrients. Body breaks down
nutrients into simpler substances which
releases energy. Metabolism is the
process whereby the body converts food
into energy (or uses it for bodily repairs)
or stores it as fat for future use.
• This energy is used to carry out metabolic
reaction.
Metabolic Rate
Metabolic Rate is the rate (and efficiency)
with which our body performs these
metabolic tasks.
Basal Metabolic Rate
Basal Metabolic Rate (or Resting
Metabolic Rate) is the number of calories
we need to burn in order to fuel essential
bodily processes and keep our organs and
tissues in working order.
Basal Metabolic Rate
• Typically, this accounts for 60 per cent of
all calories consumed. The heavier the
person, the more calories he/she needs to
fuel these essential processes.
• All other calories are used to meet our
additional energy needs based on our
level of physical activity.
Metabolic Rate
If we have a faster metabolism we burn
calories more efficiently and store less fat.
If we have a slower metabolism we burn
calories less efficiently and therefore store
more calories as fat.
Ways to increase your metabolism
• Have a hearty, healthy breakfast
• Eat six small meals a day
• Increase fiber foods – uses up more energy to
digest – lasts longer
• Limit sugary foods, processed foods, caffeine,
alcohol,& don’t smoke
• Eat fish, dark green, leafy vegetables, tomatoes,
blueberries, other berries, apples, whole grains,
• Drink 8 glasses of water per day
• Exercise regularly
WATER
• Why? – 50% – 75% body weight water, aids digestion,
cell growth, lubricates joints, regulates temperature. Can
only function a few days without water, month without
food.
• Where? – all liquids and moist foods, need average of 8
cups per day. ½ weight = fl.ozs of water needed.
• What about deficiencies? – excessive excretion
through kidneys, bowels, lungs & sweat, Dry mouth,
weakness, increased pulse, fever – dehydration and
death. Thirst is a symptom you need water.
• Increase intake for certain diseases e.g. high blood
pressure, excess heat, and excess exercise