CONDITIONS
Cardiovascular disease
Diabetes Mellitus
Colorectal Cancer
Obesity
Osteoporosis
YOU MUST TAKE INTO ACCOUNT:
The function as a determinant of health
Major food sources of protein, carbohydrate including fibre, fats- mono, poly,
saturated and trans, water, calcium, phosphorus, sodium and vitamin D.
CARBOHYDRATES
Carbohydrates are considered a macronutrient as we tend to need relatively large
quantities each day. The main function of carbohydrates is to provide fuel for
energy. When food is eaten, the body metabolises the carbohydrates in the food
into useful glucose molecules, the most basic form of carbohydrate. Glucose
molecules are then used for energy production. In terms of energy production,
one gram of carbohydrate produces 16 kilojoules of energy.
CARBOHYDRATES
Glucose molecules (and therefore carbohydrates) not used by the body for energy are
stored as adipose (or fat) tissue. This process can be reversed if glucose is
needed by the body. For example, in times of starvation, fatty tissue can be
broken down and converted back into glucose to be used for energy. If continually
eaten in excess, carbohydrates can contribute to obesity and related conditions
such as cardiovascular disease, diabetes mellitus and colorectal cancer.
SOURCES OF CARBOHYDRATES
fruits such as oranges, grapes and bananas
starchy vegetables such as potatoes and parsnips
corn
beans
pasta
bread
rice
breakfast cereals such as wheat biscuits and bran.
FIBRE
The main function of fibre is to regulate the functioning of the digestive system.
Adequate fibre intake prevents constipation by adding bulk to faeces and assists
in removing waste products through the digestive tract.
FIBRE
Technically a type of carbohydrate, fibre is made up of the indigestible parts of plant
matter found in cereals, vegetables and fruits. Foods that are high in fibre,
particularly fruit and vegetables, are usually rich in vitamins and minerals and low
in fat, which can improve health and reduce the risk of a number of NHPA
conditions
FIBRE
Colorectal cancer: Although the relationship between fibre intake and the development of colorectal cancer is still
unclear, societies that eat high-fibre diets have much lower rates of colorectal cancer.
Obesity. By providing a feeling of fullness without the kilojoules, a food intake high in fibre can reduce the amount
of energy consumed from other foods.
Diabetes mellitus. Fibre has been shown to reduce the absorption of glucose from the small intestine. This can
decrease the risk of obesity and associated conditions such as diabetes mellitus.
Bran, which is found in many breakfast cereals, is a good source of fibre. Unfortunately, too few people get
enough of this nutrient.
Cardiovascular disease. Fibre reduces blood cholesterol levels by binding to bile. Bile is released into the stomach
to assist in the digestion of dietary fat. Once the fat is 210 digested, bile is normally reabsorbed into the
blood stream. Fibre binds with bile and excretes it, preventing it from being reabsorbed. The liver makes
more bile to replace what has been excreted. Cholesterol is a key component of bile, so bile production
reduces the amount of cholesterol in the blood. Foods high in fibre generally have lower saturated fat
content, which further reduces the production of cholesterol.
SOURCES OF FIBRE
The Australian Heart Foundation recommends that adults eat between 25 and 30
grams of fibre every day. Children should consume 10 grams plus one gram for
every year of age (for example, 20 grams for a ten-year-old).
SOURCES OF FIBRE
bran flake cereal
wholemeal bread
fruit and vegetables — particularly good sources include raspberries, apples,
bananas, pears, oranges, peas, potatoes, broccoli and corn
baked beans.
Fibre absorbs water, so if the amount of fibre in the diet is increased, water
consumption should also be increased.
PROTEIN
Protein is considered a macronutrient. The primary function of protein is the growth,
maintenance and repair of body cells. However, as a secondary function, protein
is also used as a fuel for energy production. This means that if there are
insufficient carbohydrates and fat for energy use, then protein may be used.
Protein that has been converted into muscle and other tissues can also be used
as a fuel source during times of starvation. Protein yields approximately 17
kilojoules per gram when being used for energy. Excess protein may be converted
into glucose and then stored as fat if not used for growth, repair or energy. As a
result, excess protein intake can contribute to obesity and related NHPA
conditions such as cardiovascular disease and diabetes mellitus.
PROTEIN
Although most people in Australia have enough protein in their diet, some people
supplement their dietary protein with products such as protein shakes in an
attempt to build muscle. According to the Better Health Channel, people taking
supplementary protein while weight training add no more muscle than those not
taking protein supplements. Excess protein intake can strain the kidneys and
liver, as they are responsible for protein metabolism. Excess protein may also lead
to excessive loss of the mineral calcium from bones, which can contribute to
osteoporosis.
PROTEIN
animal origin: – eggs – milk, cheese and other dairy products (except cream) –
beef – chicken and other poultry – fish and seafood.
plant origin: – soy products (such as tofu and soya milk) – legumes – nuts – whole
grain cereals – brown rice.
PROTEIN
Care should also be taken when choosing protein-rich foods, as some options are
more healthy than others. For example, steak is a good source of protein, but if it
is not a lean cut (that is, if it has a lot of fat around and through it), the benefits of
getting the protein from the meat may be outweighed by the extra fat that is being
consumed. Much of the fat from red meat is saturated fat, which has further
negative health implications. Fish, such as salmon, is a better option as it is rich
in protein but has half the fat of a normal steak, and only a small percentage is
saturated fat. Lentils are another good source of protein, with very low levels of
fat and high levels of fibre.
FATS
Fats (also known as lipids) are a macronutrient. The main function of fats is as fuel for
energy. Fats are a rich source of energy, providing 37 kilojoules per gram. This
explains why foods high in fat but low in other valuable nutrients are referred to
as energy-dense foods.
FATS
Fats contribute 37 kilojoules per gram, if they are eaten in excess they contribute to
weight gain and obesity and associated effects, such as increased risk of
cardiovascular disease, diabetes mellitus and colorectal cancer.
Monounsaturated fats are considered one of the more healthy types of fat, though their
energy contribution is still 37 kilojoules per gram. Monounsaturated fats can assist in the
lowering of low density lipoproteins (LDL, the ‘bad’ cholesterol) and may increase the
levels of high density lipoproteins (HDL, the ‘good’ cholesterol). The exact mechanism of
this process is not fully understood, but replacing saturated fats with monounsaturated
fats decreases the level of LDL cholesterol, reducing the risk of atherosclerosis and
cardiovascular disease. Monounsaturated fats have also been shown to decrease the
impact of impaired glucose regulation and decrease the risk of type 2 diabetes when
consumed in place of saturated fat.
Monounsaturated fats can have positive health effects. Like any fat, however, too much will
still contribute to weight gain, obesity and associated conditions.
FOOD SOURCES
Monounsaturated fats are liquid at room temperature and begin to solidify when
placed in the refrigerator.
Foods rich in monounsaturated fats include:
olive oil
avocado
canola oil
nuts
peanut butter.
Polyunsaturated fats are also considered one of the more healthy types of fat, although they
contribute the same kilojoule value as other types. The greatest gains are achieved when
saturated and trans fats are replaced with monounsaturated and polyunsaturated fats. There
are two main categories of polyunsaturated fats: omega 3 and omega 6. Both omega 3 and
omega 6 fats act to lower LDL cholesterol in the blood stream and increase HDL cholesterol,
therefore reducing the risk of heart disease. Polyunsaturated fats also have other functions:
Omega 3 polyunsaturated fats appear to promote the elasticity of blood vessels and prevent
blood clots, which can decrease the risk of heart attack and stroke.
According to the American Heart Foundation (2009), omega 6 polyunsaturated fats decrease
the impact of impaired glucose regulation and ultimately decrease the risk of developing
type 2 diabetes.
Polyunsaturated fats reduce the impact of inflammation of blood vessels and can reduce the
risk of cardiovascular disease as a result.
These two types of fats need to be eaten in appropriate ratios to achieve their full benefit.
Adults should be eating omega 3 and omega 6 fats in a ratio of about 1 : 4. Very few
people are deficient in these types of fats, but most people tend to eat too much omega 6
fat.
POLYUNSATURATED FATS FOOD SOURCES
Polyunsaturated fats are generally liquid at room temperature and when refrigerated.
Food sources for omega 3 fats include:
fish (particularly oily fish such as mackerel, trout, sardines, tuna and salmon)
soy and canola oils, and canola-based margarine. Food sources for omega 6 fats
include:
most nuts and seeds
corn, safflower and soy oils.
SATURATED FATS
When overconsumed, saturated fats are often associated with many negative effects
on health. Saturated fat has been shown to increase LDL cholesterol production
in the liver and also contains substantial amounts of LDL cholesterol, which can
contribute to atherosclerosis and cardiovascular disease. Diets high in saturated
fat have also been shown to increase the impact of impaired glucose regulation
and the risk of type 2 diabetes.
SATURATED FATS FOOD SOURCES
Saturated fats are mostly found in foods of animal origin and are usually solid at room
temperature.
The visible fat on meat is largely saturated fat.
Examples include:
fatty cuts of meat. Saturated fat can be seen along the edges and through some
meats.
full cream milk, cream and cheese
coconut milk and cream
most fried takeaway food
most commercially baked goods such as pastries and biscuits.
TRANS FATS
Trans fats behave much like saturated fats in the body by raising LDL cholesterol
levels. Trans fats also work to decrease levels of HDL cholesterol, thereby
increasing the risk of cardiovascular disease.
Trans fats can also interfere with the structure of cell membranes, which can affect
the movement of nutrients and fluids in and out of the cells. If glucose is
restricted from entering the cells, insulin levels increase in response to the higher
blood glucose levels. This can contribute to insulin resistance and increases the
risk of type 2 diabetes.
TRANS FATS
Although small amounts of trans fats are found naturally in certain foods, including
beef, mutton and dairy products, most trans fats are created when liquid oil is
converted into solid fat by a process called hydrogenation. For this reason, trans
fats are generally found in processed foods, such as pies, pastries and cakes.
Margarines and solid spreads made for cooking are sometimes high in trans fats
and should make up only a small part of the diet. The level of trans fats in
processed foods is usually found in the nutritional panels of these foods. By
consulting these labels, consumers can choose foods with little or no trans fats.
THE RELATIONSHIP BETWEEN FOOD AND BODY
WEIGHT
In order to lose, gain or maintain body weight, the balance between energy intake
(energy consumed) and energy output (energy expended) is important.
Carbohydrates, protein and fat (energy intakes) that are not used for energy
production can be stored as adipose tissue (fat), so an individual who continually
takes in more energy than they use risks becoming overweight and/or obese.
Obesity is a risk factor for many other conditions, such as type 2 diabetes,
colorectal cancer and cardiovascular disease, and can reduce an individual’s
overall level of health.
WATER
Although it has no nutritional value, water is vital for human survival. Water makes up
between 55 and 75 per cent of our body mass. Water is needed for many
functions within the body. The amount of water required daily ranges from about
1.2 to 3 litres.
As water contains no nutrients and therefore no energy, it can assist with weight
management
When consumed instead of other fluids. Regular consumption of water can reduce
the risk of obesity and related conditions such as cardiovascular disease and
diabetes.
Water is also absorbed by fibre and therefore plays a role in digestive health and the
prevention of colorectal cancer.
SOURCES OF WATER
Most people’s daily intake of water does not come from drinking water at all. In fact,
all food and drink contains water, and this is where most people get a majority of
their supply. Water in its purest form is the best source, as many other fluids
contain additional kilojoules (as a result of added sugars and other additives) and
no other valuable nutrients.
Major sources of water include:
water in its pure form
other drinks that contain water, such as cordials, soft drinks, tea and coffee
fruits, including apples, watermelon, oranges, grapefruit and tomatoes
vegetables such as celery, broccoli, lettuce, carrots and cucumber.
CALCIUM
Calcium is the most abundant mineral in the body. Most of the calcium in our bodies
(about 99 per cent) is stored in the bones, with the other one per cent in the
blood, muscles and intracellular fluid. Perhaps the most important role of calcium
is as a hardening or ossifying agent for hard tissue such as teeth, bones and
cartilage. Calcium is capable of moving in and out of the bones and will move out
of the bones if there are insufficient amounts available in the blood for other body
functions.
If an individual does not get enough calcium throughout their life, they are less likely
to achieve their optimal peak bone mass. The more bone mass that is built up in
the early years (particularly during youth), the greater the chance the person has
of maintaining good bone health throughout life. If optimal peak bone mass is not
achieved, the individual is at greater risk of developing the NHPA condition of
osteoporosis and suffering from fractures later in life
CALCIUM
The growth of hard tissue starts with the laying down of the bone matrix, which is like
a framework for the bone structure. The bone matrix is largely made up of
collagen, which consists of protein and vitamin C and provides ‘storage holes’ for
calcium phosphate. Once the matrix is in place, crystals of calcium phosphate fill
the holes, which makes the tissue strong and hard. This process is known as
ossification.
Ossification is much like dipping a sponge into a bucket of plaster. The once-soft
sponge maintains its shape but becomes very hard as the plaster dries. The
matrix is like the sponge and the calcium phosphate is like the plaster. They are
both needed for adequate bone formation.
Once bones have stopped growing, ossification continues to replace old crystals with
new ones. As people age, this process becomes less efficient and more crystals
need replacing than the body can produce. This leads to weaker bones after the
age of about 30
FOOD SOURCES OF CALCIUM
Good sources of calcium are dairy products such as milk, cheese and yoghurt. Other
sources include:
sardines and salmon (with bones)
green leafy vegetables, such as broccoli and spinach
fortified soy milk
tofu made with calcium sulphate
fortified orange juice.
PHOSPHORUS
Phosphorus has a number of roles in the body. Its main function is to work with
calcium to harden or ossify bones and teeth. Calcium and phosphorus bind to
form calcium phosphate, which is the ossifying agent for hard tissue.
adequate intake of phosphorus is important to decrease the risk of developing
osteoporosis.
Calcium and phosphorus are required to maintain the health of bones.
Australians tend to get sufficient phosphorus in their diet, but certain conditions, such
as diabetes and alcoholism, can prevent it from being absorbed, leaving the
individual with low levels of phosphate. This can cause loss of bone density,
weakness and poor appetite.
FOOD SOURCES OF PHOSPHORUS
As phosphorus is an important part of all living things, it is found in most foods. Foods
that are rich in protein are particularly rich in phosphorus and include:
dairy products such as milk, cheese and yoghurt
meat such as chicken and beef
eggs
fish
nuts
legumes.
SODIUM
Sodium is an important mineral for human life. It plays a role in the regulation of
fluids in the body, including water and blood. Fluid is drawn to sodium, so the
amount of sodium in the blood influences the amount of fluid that stays in the
cells. Through this mechanism, sodium regulates the balance between fluid in the
cells (intracellular fluid) and the fluid outside the cells (extracellular fluid).
Most Australians get more than enough sodium in their diet. According to the Better
Health Channel, the average Australian consumes eight to nine times the amount
of sodium they need for good health. High levels of sodium in the body can draw
excess fluid out of the cells. This increases blood volume and contributes to
hypertension.
SODIUM
Effects linked to excessive sodium intake include:
heart failure. Increased blood volume and hypertension force the heart to work
harder. Heart failure can result if the heart cannot keep up with demand from the
body.
stroke and heart attack. Hypertension associated with excess sodium intake
contributes to higher rates of stroke and heart attack.
osteoporosis. Excess sodium causes calcium to be excreted in urine, which can lead
to the demineralisation of bones and the NHPA condition osteoporosis.
Excess sodium increases blood volume and contributes to hypertension.
FOOD SOURCES OF SODIUM
Foods containing sodium include:
table salt
olives
fish
meat (especially pork)
cheese
many processed foods, such as tomato sauce, packet soups and sauces, canned
vegetables, pizza, pies and ready meals
VITAMIN D
Vitamin D is required for the absorption of calcium and phosphorus from the intestine
into the blood stream. Due to the essential role that calcium and phosphorus play
in the formation of hard tissue such as bones and teeth, a lack of vitamin D leads
to weakened bones and teeth. Osteoporosis (weak, frail bones) is a common
musculoskeletal conditions caused by a lack of vitamin D.
VITAMIN D
Most Australians get their vitamin D requirement from exposure to ultraviolet (UV)
rays (from sunlight). UV rays are converted to vitamin D in the skin. Vitamin D
deficiency was not a major concern in the past, as most Australians were exposed
to enough UV rays to synthesise adequate amounts of Vitamin D. However, as
more and more people heed the sun safety message, the amount of exposure to
UV rays has decreased, and vitamin D deficiency is becoming more common. This
is particularly the case in elderly people, as they are more likely to spend
extended periods indoors.
VITAMIN D
Vitamin D does not occur naturally in many foods. Fish (particularly tuna, salmon,
mackerel, sardines and herring) is the best source of vitamin D. Small amounts
can also be found in beef liver, cheese and egg yolks.
Some brands of milk, breakfast cereals and orange juice are fortified with vitamin D,
but it is important to check the packaging.