Nutrition and Diseases

An improper or inadequate diet can lead to a number of diseases. On the other hand, good nutritional habits can help prevent certain diseases.

Heart disease in its most common form is called coronary artery disease (CAD). CAD narrows the coronary arteries and so reduces the blood supply to the heart. It can lead to crippling attacks of chest pain and, eventually, to life-threatening heart attacks. High blood pressure and high levels of blood cholesterol are two of the major risk factors for CAD. Each of these risk factors can often be lessened by following good nutritional practices. Many people with mild high blood pressure can reduce it by limiting their intake of salt and calories. Similarly, many people can lower their blood cholesterol level by reducing the j amount of cholesterol, fat - particularly saturated fat - and calories in their diet. They can do so by avoiding such foods as butter, cakes, cookies, egg yolks, fatty meats, tropical oils, and whole-fat dairy pro­ducts.

Cancer. Scientists do not know exactly why cancer develops. But they have found that heredity, environment, and life style all play a role in causing the disease. They have also learned that good nutrition can help prevent certain kinds of cancer in laboratory animals. Large doses of vitamins A and С have been proven to prevent some cancers i in animals. Many scientists believer that certain foods contain sub­stance that may help prevent some cancers in people. Such foods in­clude broccoli, cabbage, carrots, cauliflower, fruits, spinach, who-legrain breads and cereals, and some seafoods. Lessening the intake of fats and increasing the intake of fibre may also help prevent some cancers from forming.

Deficiency diseases. Many diseases result from the deficiency (lack) of certain nutrients in the diet. When the missing nutrient is provided, the disease usually can be eliminated. Deficiency diseases are mosl widespread in developing countries, where people often lack access to adequate food supplies. The availability of a variety of foods all the year round, along with vitamin and mineral fortification of many foods, have made deficiency diseases less common in most developed.

Protein-calorie malnutrition occurs when the diet is low in both proteins and calories. If the diet is especially low in proteins, the con­dition is called kwashiorkor. Signs of kwashiorkor include changes in the colour and texture or the hair and skin, swelling of the body, and damage to the intestines, liver and pancreas. The disease, which is common in some developing nations, usually attacks children who are suffering from an infectious disease. Kwashiorkor is fatal unless the patient is given protein along with food providing calories. If the diet is especially low in calories, the condition is called marasmus. Maras­mus usually attacks infants and young children, and it causes extreme underweight and weakness.

Дата добавления: 2015-08-13