Understanding Health, Disease, and Environmental Factors
Concept of Health and Illness
Currently, the World Health Organization (WHO) defines health as a state of complete physical, mental, and social well-being, not merely as the absence of disease. As for the disease, it is defined as an altered state of health, i.e., a temporary or permanent loss of physical, mental, or social well-being.
Quality of Life and Life Expectancy
A person’s quality of life is defined in general terms by their degree of comfort, happiness, and satisfaction, allowing them to act and feel their life positively. This quality of life depends, among other factors, on their physical and mental health, their level of autonomy, and their relationship with their social environment.
One of the main indicators of quality of life is life expectancy at birth, which is an estimate of the average number of years a group of people born in a year would live if health and social conditions in the area being studied do not vary. This value is closely related to health, as is life expectancy free of disability, stretching life years in good health.
Genes, Lifestyle, and Health Status
A person’s health status is the result of interaction between their genotype (the information carried in their genes) and the environment in which they develop and live.
- There are genetic diseases due to alterations in the genome. The genetic defect is the direct cause of the disease. This is the case of Down syndrome, hemophilia, or some types of diabetes.
- In other cases, the genotype does not directly determine the presence of the disease but the predisposition to it. For example, a person may be predisposed to cardiovascular disease, but the environment in which they live also plays a role. If they follow a proper diet and exercise, they may never develop the disease.
A group within genetic diseases are congenital diseases. These appear from birth due to some disturbance during development in the womb or during childbirth. Many are also genetic diseases, like Down syndrome. Others, however, are due to environmental factors. For example, when a pregnant woman suffers from measles, it can be transmitted to the fetus and may result in mental retardation. Today, many congenital diseases can be diagnosed before birth. At times, moreover, they can be cured.
Environmental Hazards and Health
Health is subject to a number of diseases, injuries, and risks that can originate in various areas:
- The environment around you
- The body itself
- Lifestyle
- The sociocultural context
The diseases that affect people are classified according to the location affected (heart, liver, kidney, etc.) or the cause. The most useful classifications combine both criteria.
Environmental Hazards
We do not inhabit a paradise. Life is an exercise in the struggle for survival in which organisms face adverse physical and chemical environmental conditions, as well as other organisms that affect health. We can classify such hazards in the following table:
- Physical Environmental Hazards
- Ionizing radiation
- Noise
- Temperature variations
- Pollution
- Air pollution
- Water pollution
- Contamination of food
- Biological Hazards
- Viruses
- Bacteria
- Fungi
- Protozoa
Ionizing Radiation
Ionizing radiation is a form of energy that is capable of modifying the structure of matter, so it can cause changes in our cells, some of which may alter the state of health. It can have a natural origin (the Sun’s ultraviolet rays and some gamma rays; beta and gamma radioactivity from some minerals and rocks) or artificial (nuclear waste).
Noise
Most of the world’s population lives in cities, a noisy environment. Noise is unwanted sound that can induce alterations in sleep and behavior, and hearing loss. Although traffic is the main source of noise, for young people, the sound is often glued to their ears. The continued use and abuse of headphones for music may result in hearing loss in the future because, although the intensity of music played may seem low, its proximity to the eardrum makes it dangerous.
Temperature Variations
High temperatures, combined with excessive moisture that prevents the evaporation of sweat and the cooling it entails, can be lethal. Extreme cold, on the other hand, also causes injuries. Mortality from other diseases increases when heat or cold are intense.