The
funcion of the substance we eat
The most recent researches on nutrition show us that we haven’t
learnt yet the right way of eating: we eat too much calories and only
few nutritional substances. Everybody need a self-training on the
right nutrition, starting from a better knowledge of the food.
Carbohydrates
The carbohydrates represent the main source of energy for our body.
They play a very important role for our brain activity and are divided
into two forms:
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Simple sugars which are immediately assimilated
from the blood.
They provide us with calories, without any other nutritional
substance. |
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Complex sugars (starch) which are slowly
assimilated from our blood. Food containing starch are rich
not only in calories, but also in vitamins, fibres and minerals. |
The main sources of simple sugars are: common
sugar (sugar beet derivative), sugar beet, fruit, honey and sweets.
The main sources of complex sugars are: cereals
(wholemeal in particular) and vegetables.
Fats
Fats are great energy suppliers: they have 9 calories per gram,
twice the quantity contained in carbohydrates. Much of them are
necessary to our body because they help us to absorb liposoluble
Vitamins A, D and E.They are divided into two forms:
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Saturated fats. It is suggested
to avoid a high consumption of saturated fats, because they
increase the cholesterol level in blood. |
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Unsaturated fats. They are divided in mono-saturated
and poly-saturated. Some poly-saturated fats (such as Omega
6 and Omega 3 oil) are of fundamental importance for the brain,
the nervous system, the immune system, the cardiovascular system
and the skin. |
The main sources of saturated fats are: meat and dairy products.
The main sources of unsaturated fats are: olive oil (rich in mono-saturated
fats) walnuts, seed oil, fish.
Proteins
Proteins are a combination of more than 20 different amino-acids.
Eight of them are of fundamental importance for us, and since our
body is not able to produce them, they have to be absolutely introduced
through the food.
They are not only very important for the growth, but even for the
production of hormones, enzymes, antibodies and they help the distribution
of substances throughout the whole body. The quality of proteins: the “biological valence” or
quality of proteins depends on the quantity of amino-acids in protein
and on their links. Animal proteins have a higher biological valence
compared to the vegetal ones.
If we combine together different vegetal proteins or vegetal proteins
with some animal proteins, our proteic quality becomes higher than
that obtained from the assumption of single animal proteins.
Some of such rich combinations have been found in:
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Legumes associated with wheat or rye |
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Potatoes associated with eggs, milk, ricotta cheese or cheese
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Cereals (bread, pasta) with milk, meat or fish |
The proteic source of a balanced nourishment should be half (50%)
of animal origin and half of vegetable origin.
The main sources of proteins are: eggs, meat,
fish, beans, lentils, peas and soya (very high proteic content foods);
cereals, cabbages, potatoes and cheese (moderate proteic content
foods).
Vitamins
Without vitamins it is impossible to live. They are necessary for
the growth and for all the life functions: they reinforce the immune
system, they are essential for our brain and nervous system, they
regulate the skin health and the hormonal equilibrium.
Vitamins A, C, and E have an antioxidant action and therefore they
help to slow down the aging process, to prevent cancers, heart disease
and they protect the body against pollution.
Vitamins B and C are necessary to convert food in physical and
mental energy.
Vitamin D helps maintaining the balance of calcemia and it can
be produced by the skin thanks to solar rays action.
The nutritional sources of A Vitamin are: meat,
fish, eggs and dairy products, where it is contained in form of
retinol; yellow, orange and red coloured fruits and vegetables,
where it is contained in form of ß-carotene.
The nutritional sources of B and C vitamins are:
fresh fruits and vegetables
The nutritional sources of D vitamin are: milk,
meat, fish, eggs and dairy products
The nutritional sources of E vitamin are: seeds,
walnut and oil obtained from them
Minerals
Minerals are as necessary as vitamins are for all our body
functions. They are of fundamental importance for bones and teeth,
for blood coagulation, for the transmission of nervous impulse to
the nervous and muscular cells, for the regulation of water equilibrium,
for the prevention of the decay and the formation of thyroide hormones.
Depending on the need, they are divided into:
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Constitutional elements; a high concentration
is contained in our body, they are daily necessary in different
gram quantities. Constitutional mineral substances are sodium,
potassium, calcium, phosphor, magnesium and chlorine. |
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Trace elements, infinitesimal quantities are contained in
our organism; our need is in millionth of grams. Trace elements
are iron, iodine, fluorite, manganese, copper, zinc and selenium. |
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Main nutritional sources of potassium are: legumes, potatoes,
cabbages, artichokes, carrots, spinaches, mushrooms, truffles,
bread. |
Main nutritional sources of calcium are: milk
and derivatives, spinaches, cabbages and broccoli.
Main nutritional sources of phosphor are: salmon
and sardines, liver (pig, calf, beef and mutton, bread, legumes,
artichokes and mushrooms.
Main nutritional sources of iron are: red meat,
entrails, cereals, legumes, artichokes, spinaches, fennels, mushrooms
and truffles.
Main nutritional sources of fluorine are: lobsters,
sardines, kippers, entrails, walnuts, legumes and spinaches.
Fibres
Fibres are “carbohydrates that cannot be used”, that
is they are not assimilated by our body. They have different important
functions.
Fibres in fruits and vegetables help to slow down the absorption
of sugars in blood, maintaining a good energy level.
Fibres in cereals are particularly indicated to prevent constipation,
which causes many digestion troubles.
Main nutritional sources of fibres are: beans,
peas, wheat shoots, cabbages, carrots, apples and pears.
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