food, nutrition and health Flashcards
source, function, excess, deficiency
what are some sources of protein? (name 4)
meat
fish
dairy products
nuts
seeds
beans
what is a high biological value protein?
HBV proteins contain all of the essential amino acids we need.
what is a source of HBV proteins (name 2 animal and 2 plant)
animal sources
meat
fish
poultry
eggs
cheese
milk
plant-based sources
soya beans
quinoa
what is a low biological value protein?
LBV proteins are missing one or more of the essential amino acids we need.
what is a source of LBV proteins (name 2 plant)
only found in plant sources like:
peas
lentils
nuts
seeds
most beans
and smaller amounts in:
veg like spinach
broccoli
what is protein complementation?
if we don’t get enough HBV proteins, we have to combine LBV proteins to get all the essential amino acids in our diet
e.g. hummus and pita are both LBV but combine to give right amount of essential amino acids
or veg lasagne
what is the function of proteins?
growth- e.g. from childhood to adulthood, and for growth of nails, hair and muscle mass
repair- e.g. repairing muscles, tissues and organs after illness or injury
maintenance- e.g. to make enzymes for digestion and antibodies to stop getting ill
what are proteins made up of?
amino acids. building blocks of the body
the amino acids our body makes are non-essential amino acids but we have to eat essential amino acids which our bodies do not make
what are dietary reference values?
estimates of the amount of nutrients people should have in their diet.
average female- 45g protein
average male- 55g protein
growing children need more relative to their size and body mass.
pregnant women need about 6g more.
physically active people need more for muscle growth + repair
what is the effect of excess protein?
the liver and kidneys help process proteins. too much of it puts a lot of pressure and strain on these organs. dangerous
what is the effect of protein deficiency?
slowed growth, especially in children.
hair, skin, and nails don’t grow as fast and become in poor condition.
poor immune system slow healing wounds and higher risk of infection.
digestion problems so body struggles to take in nutrients.
oedema- build up of fluid causes swelling.
what are some alternative proteins? (name 4)
soya- HBV, eaten whole but cooked to remove toxins, soya milk, salads and processed to make tofu and TVP
mycoprotein- made from mushroom-like fungus and egg white, good chicken alternative
TVP- made from soya beans can ne made into sausages or burgers
tofu- curdled soya milk can be used in dips and desserts or in stir fries because of its flexibility in texture
what is the function of fats in the body?
they provide a concentrated source of energy twice as much as proteins and carbs in g
source of fat soluble vitamins ADEK
forms insulating layer under skin to keep us warm also layers protect bones and organs (e.g. heart, kidneys)
fat used to make cholesterol, essential part of cell membranes
what are fats made up of?
fatty acids, glycerol in form of triglycerides
what are fatty acid chains?
Made up of carbon and hydrogen. Can be saturated or unsaturated - the difference is the bonds between carbon and hydrogen atoms.
saturated fatty acids…
have single C-C bonds
unsaturated fatty acids…
contain at least one C=C double bond in their carbon chains
how do you know if its saturated or unsaturated fats?
our body breaks down fat into fatty acids during digestion - the ratio of saturated to unsaturated fatty acids decides whether it’s a saturated or unsaturated fat
why are saturated fats generally unhealthy?
solid at room temp and tend to come from animal sources such as meats, butter, lard, suet and cheese but also from plant sources like coconut butter.
too much of it increases cholesterol levels and increases risk of CHD
why are unsaturated fats healthier?
usually soft or liquid at room temp and come from vegetable sources high in fat (e.g. flax seeds and peanuts) and vegetable oils (e.g. sunflower oil)
they can be monounsaturated (contain one C=C double bond found in olive oil, avocado, almonds) or polyunsaturated (contain more than one C=C double bond found in sesame oil, seeds, oily fish)
by replacing saturated with unsaturated fats this can lower blood cholesterol
how much fat should be in our diet?
government guidelines suggest fat should make up no more than 35% of our food energy per day and no more than 11%M should be saturated.
average adult should have about 70g with no more than 20g of this saturated
what is the effect of excess fats?
weight gain.
obesity.
obesity can lead to type-2 diabetes, where the body struggles to control blood sugar levels
too much saturated fats can increase blood cholesterol levels this can restrict blood flow.
this increases high blood pressure, stroke, heart attack and CHD risk.
what is the effect of fat deficiency?
fat soluble vitamins are absorbed by the body so vitamin deficient.
weight loss if carbs are low and there is not enough fat to use for energy.
less insulation so colder faster.
thinner layer of fat to protect skin and body from knocks.
what are the two types of carbohydrate?
sugar and starch.
what are sources of sugar carbohydrates?
e.g. glucose and fructose can be found in foods naturally like fruits and vegetables.
OR
they can be added during the manufacturing process like cakes sweets and fizzy drinks
added sugars (empty calories) they have no nutritional benefits other than energy