 |
 |
 |
 |
 |
 |
|
|
|
|
|
|
|
The five food groups approach is just one way of thinking about food. There is no
particular
nutrient basis for the five food groups, although such reasons are often suggested. Take a
nutrient
like protein, for example, which is found in significant quantities in animal products like meat,
fish,
eggs and milk, and also in plant derived foods like cereals, legumes and even root vegetables
like
potatoes. The nutritional quality of the protein, or rather the amino acids that make up the
protein, differs, and if amino acids are only obtained from plant foods, it is advisable to have
complementary protein sources from, for example, cereals and legumes, even at the same meal
to
ensure that all essential amino acids are obtained. With a plentiful food supply, however, even
this
is not very critical.
Iron can be obtained from cereals, but its bioavailability (availability for absorption into
the body)
depends on the simultaneous eating of, for example, vitamin C containing fruits or vegetables
or
of some meat; it is not necessary to have meat to get iron.
For a favourable calcium balance (when no more calcium is lost from the body than is
consumed)
it is not necessary to have dairy products. Calcium can also be obtained from a variety of
foods
such as green vegetables, legumes (beans) and nuts. There are many factors in food which
reduce
the calcium in the body, for example sodium, caffeine, protein and alcohol, and some people
may
need additional calcium (see
WOMEN NEED MORE CALCIUM THAN MEN).
Indeed the strength of the food group classification is its emphasis on foods rather than
nutrients.
There are many interesting chemicals in food which have not been defined as nutrients, but
which
may be physiologically important. For a long while dietary fibre or roughage was thought a
useless part of food, but now it is regarded as very important for human health. It is found in
unrefined plant foods, but not at all in animal derived foods.
So there may be other useful ways of grouping foods, depending on the nutritional
question.
Some examples would be:
According to biological source:
The advantages of this approach are that it allows people to identify the key nutritional
characteristics of a food and encourages choice from a wide variety of different foods. Greater
variety tends to lessen the likelihood of chronic nutritionally related disease, be safer and make
it
more likely that you will obtain the full range of nutrients required. Appendix 4 provides further
information on grouping food according to their biological source.
2. According to time of day eaten:
According to likelihood of protecting against or contributing to chronic disease like
coronary heart disease, non-insulin dependent diabetes, gall bladder disease, obesity,
large bowel cancer, cirrhosis of the liver and osteoporosis (thin bones):
CONTRIBUTE
PROTECT
This approach to food selection, through a knowledge of foods that contribute to and
foods that
protect against disease is often called 'the prudent diet'.
The prudent diet may vary from one culture to another. For example, in a country where the main health problems are protein-energy malnutrition, nutritional anaemia, blindness due to vitamin A deficiency, or iodine deficiency disorders like goitre and the medical condition of cretinism, a prudent diet would include foods that help prevent these conditions.
It is interesting and important to look at the way different people group foods
instinctively or
according to their cultural background. Examples would be:
MORAL
FAMILY
SOCIAL OCCASION
The moral, family and social roles of food cannot be easily separated from the nutritional
roles.
Recent evidence indicates that the social occasion of eating may have health-related effects in
its
own right.
Thus it can be seen that a particular food group classification needs to be seen in its
historical,
educational, social and medical context. There is no one 'best' way of choosing food.
|
|
|
|
|
|
|
