What are the Main Causes of Disease

What are the Main Causes of Disease

Sources (causes) of Disease :

Generally, factors affecting health may be divided into following groups –

1. Intrinsic factors and
2. Extrinsic factors

1. Intrinsic or Internal Factors :
The disease causing factors which exist with in the human body are called intrinsic factors.
The important intrinsic factors which affect human health are the following –

1. Malfunctioning or improper functioning of various body parts.
2. Genetic disorders
3. Hormonal imbalances
4. Malfunctioning of immune system

The diseases caused by intrinsic sources or factors are called organic or metabolic diseases.
Some of the diseases caused by intrinsic sources are –

1. Cardiac failure
2. Kidney failure
3. Osteoporosis (Pore in bones)
4. Myopia or short sightedness
5. Sickle cell anaemia etc.

2. Extrinsic or External Factor :
The factors causing diseases and existing outside the human body are called extrinsic or external factors.
The important extrinsic factors which upset human health are the following –

1. Unbalanced diet
2. Diseases causing micro-organism such as viruses, bacteria, fungi etc.
3. Environmental pollutants.
4. Tobacco, alcohol and narcotic drugs.

Extrinsic factors affect the health of our body by interfering with normal fuctioning of the body system.
Some of diseases caused by extrinsic factors are–

1. Kwashiorkor
2. Marasmus
3. Night blindness
4. Beri Beri etc.