diet Flashcards
why do we need food
provides us with the energy to do work
to carry out vital functions of the body
substances that our body needs for good health and resisting diseases
the building materials needed for growth of new cells and the repair of damaged cells
what is energy in food measured in
joules J or kJ
Calories Cal or kCal
how is food classified
classified into 7 main food groups based on types of nutrients these foods provide for the body
define nutrients
chemical substance in food essential for proper functioning of your body
what are the five processes that is in involved in the heterotrophic nutrition
ingestion: the process by which food is taken into the body via the mouth
digestion: the process by which food is broken down into simple soluble food molecules
absorption: the process by which soluble food molecules, produced in digestion, move into body fluids and body cells
assimilation: process by which the body uses soluble food molecules absorbed after digestion
egestion or defaecation: process by which undigested food material is removed from body
define a balanced diet
made up of food from all food groups in correct amounts to meet the needs of the individual to supply the body with enough energy for daily activities and the correct materials for growth and development and to keep the body in a healthy state
state functions for carbs
to provide energy as main source for the body
17kJ per g
energy is easily released when respired
for storage
glycogen granules are stored in many cells
sources for carbs
sweet foods – fruits cakes jams
starchy foods – yams potatoes rice
deficiency for carbs
weight loss
can contribute to marasmus along with deficiency of other food groups
carbs taken in excess
weight gain
leads to obesity and other related diseases
state protein functions
to make new cells for growth and to repair damaged tissues
to make enzymes which catalyse reactions in the body
to make hormones which control various processes in the body
to make antibodies to fight diseases
to provide energy 17kJ per g used only when stored carbs and lipids have been used up
sources of proteins
fish lean meat milk cheese eggs peas beans nuts
deficiency of proteins
loss of body mass
wasting of muscles
kwashiorkor
proteins taken in excess
broken down in liver and excreted by kidneys
not stored
functions of lipids
to make cell membranes of newly formed cells
to provide energy 39 kJ per g used after carbs because their metabolism is more complex and takes longer
for storage fat is stored under the skin and around organs
for insulation fat under skin acts as an insulator
sources of lipids
fats from animals – butter chocolate fry foods
fats from plants — olive oil avacado nuts seeds
deficiency of lipids
contributes to marasmus
if lipids taken in excess
weight gain
obesity
heart disease
hypertension
define vitamins
organic compounds that are required in small amounts for healthy growth and development
micronutrients
vitamin a source
liver
carrots
pumpkin
spinach
vitamin a function
helps to keep skin cornea and mucous membranes healthy
helps vision in dim light (night vision)
strengthens the immune system
vitamin a deficiency
dry unhealthy skin and cornea
increased susceptibility to infection
reduced vision at night or complete night blindness
xerophthalmia – eyes fail to produce tears leading to a dry damaged cornea and sometimes blindness
vitamin b1 source
whole grain cereals
bread
brown rice
peas
beans nuts
vitamin b1 functions
aids in respiration to produce energy
important for the proper functioning of the nervous system and the heart
vitamin b1 deficiency
beri beri –weakness and pain in the limb muscles
difficulty walking
nervous system disorders
paralysis
vitamin b3 sources
fish
lean meats
whole grain cereals
yeast extract
vitamin b3 functions
aids in respiration to produce energy
vitamin b3 deficiency
pellagra – skin digestive system and nervous system disorders resulting in dermatitis and diarrhoea and dementia
vitamin c source
oranges
papayas
west indian cherries
vitamin c functions
keeps tissues healthy
especially skin and connective tissue
strengthens immune system
for absorption of iron by bones
vitamin c deficiency
scurvy – swollen and bleeding gums, loose teetu or loss of teeth, red blue spots on the skin, muscle and joint pain, wounds do not heal
increased susceptibility to infection
vitamin d source
oily fish
eggs
cod liver oil
made in the body by action of sunlight in skin
vitamin d functions
promotes absorption of calcium and phosphorous in the ileum
helps build and maintain strong bones and teeth
strengthens immune system
