5. Trastornos relacionados con la alimentación.

BIOGEOSPHERE Bilingual Biology and Geology I.E.S. "J.S.Elcano (Sanlúcar Bda.)

Unit 2: Food and nutrition 1 2 3 4 5

5. Nutritional disorders and diseases

Food-related diseaseses are those which are due to malnutrition or bad diet, as well as different forms of food poisoning, caused by the consumption of food or drink contaminated by microorganisms.

a) Malnutrition

An inadequate diet can cause disorders in the body and illness,

which can be serious or even fatal.

Malnutrition occurs when the quantity of food eaten is not enough to satisfy the body's nutritional needs. There are different types of malnutrition. The main ones are:

- Undernutrition:

- Wasting or marasmus, which happens when there is

prolonged dietary deficiency on protein and calories.

It is typical of underdeveloped countries

of the Third World which suffer starving.

- Kwashiorkor, which is caused by a serious lack

of protein in the diet.

- Deficiency Diseases

- Inadequate ingestion of some vitamin.

Avitaminosis is caused by the lack or deficiency.

An example of avitaminosis is scurvy, caused by

a lack of vitamin C.

In contrast, hypervitaminosis occurs, when

vitamins may accumulate in the organism.

- Inadecuate ingestion of some mineral. An example is rickets, which is caused by the lack of calcium and phosphorus. It causes deformities of the bones and deficient growth. This illness is common in poor countries, due to the lack of food.

- Psychological diseases related to feeding

- Anorexia nervosa is due to a psychological disorder which means that the sufferer has a distorted image of his or her body. Because of this disorder, frequent among adolescents, the sufferers are afraid of gaining weight, so they do excessive physical exercise and follow a very strict diet.

- Bulimia is often accompanied by anorexia nervosa. Those who suffer from this disease eat enormous amounts of food and then provoke vomiting so that they don't gain weight.

- Overnutrition

The illness caused by eating

too much includes obesity,

characterised by excessive body

fat. Obesity is a risk factor for

those with heart diseases,

diabetics (who accumulate a large

amount of glucose in the blood)

or those suffering from hypertension

(people whose arterial blood pressure

is higher than that which is healthy).

b) Food poisoning

Food poisoning may occur from eating food contaminated with bacteria, viruses, protozoa or other parasites; or because of the ingestion of food contaminated with chemical substances, such as pesticides, for example.

The main types of food poisoning caused by bacteria are salmonellosis

and botulism.

- Salmonellosis is caused by eating food

contaminated with bacteria of the Salmonella

genus. These bacteria are usually found in

contaminated water, badly conserved

foods containing egg (mayonnaise, sauces,

etc.) and meat. Its symptoms are headaches,

vomiting and diarrhoea. It is particularly

serious in children and old people.

- Botulism is caused by eating food contaminated with the toxins produced by the bacteria Clostridium botulinum. This illness is characterised by the appearance of neurological disorders and it can be lethal. The usual cause is eating tinned food in bad condition.