|What are nutrients?
A balanced diet contains a range of
nutrients, all of which play an important part in keeping our
bodies healthy. The nutrients in our food are classified as
proteins, fats, carbohydrates, vitamins, minerals and
Protein is the main constituent of all body
cells. It provides the material necessary for growth and the repair
and maintenance of the body. Protein is found in many of the foods
we eat like cereals and breads, milk and cheese, meats and eggs and
fish. It is important to eat a variety of these foods as the body
needs a variety of proteins to do its job.
Fats are a fuel to provide energy for our
bodies. They also act as a layer on the body for insulation, to
keep out the cold and to protect against injury. The chief sources
are butter, margarine, cooking oils as well as fats in foods such
as cheese, meats and snack foods. The surplus fat we eat is
converted into stored body fat, so it is important not to eat too
Carbohydrates also act as a fuel to provide
us with energy. Carbohydrates occur as either starches or sugars.
The most useful carbohydrates are those found in cereal foods, such
as breads, rice, pasta, oats, and starchy vegetables like potatoes,
dried beans and peas. Any surplass is converted by the body and
stored as fat.
Minerals are required in very small
quantities per day, however they are essential for on-going health.
Some of the main ones are as follows:
Calcium is found primrarily in milk and
cheese, but also in vegetables. Calcium plays a large part in the
development and maintenance of bones and teeth, as well as playing
a part in blood clotting, muscle contraction and nerve
Iron is necessary for the production of blood.
Bloods cells are being created and destroyed at a rate of about 2
million per second, with red blood cells having a life-span of
about 120 days. Despite this astounding output, the daily
requirement of iron is about 0.012g per day, which can be gained
from foods such as beef, muesli, wholemeal cereals, nuts, baked
beans, oats, eggs and fish.
Phosphorus, like magnesium and calcium, is
used in bone and tooth formation, as well as enzyme activity in
metabolism. Found in foods rich in protein, it is also found in
whole grains, nuts and seed.
Zinc is an essential trace element, which has
a variety of functions in the body. It is related to the absorption
and action of vitamins, and it is a constituent of many enzymes. It
is also a component of insulin. Like all trace elements, zinc is
found in protein foods like meats, seafoods, and nuts. Wholegrain
cereals, milk and eggs are also good sources.
Vitamins are highly complex, and fragile,
organic compounds which are essential to maintain a healthy body.
Small amounts must be absorbed from food each day, as generally
they can't be synthesised by the body.
Although fibre doesn't provide us with
energy or essential nutrients, it provides the bulk to carry the
waste products of digestion out of the body.
Brandreth, G. Vital
Statistics. (New Jersey: Citadel, 1986).
National Food Authority Food for
Health (Canberra: Australian Government Printing, 1991).
Nutrition Search Inc. Nutrition
Almanac (New York: McGraw-Hill, 1975).
Pyke, M; Moore, P. Everyman's
Scientific Facts and Feats (London: J M Dent, 1981).
Britannica Online. Vitamin E