Evolutionary Health
Co-Evolution of Disease & Living Conditions
Health Effects
What is Risk?
Environmental Risk
Risk Assessment
Risk Abatement
Risk Perception
Risk Management
Uncertainty & Other Features of Risk Assessment
Precautionary Principle
Appendix 1: Contaminants
Appendix 2: Environmnet & Reproductive Health
Internet Links
Other Resources
Health & Risk System PDF
Printer-Friendly Web Version


Introduction: What is Health?


List the major aspects that determine a person's health. Rank these by importance, taking into account the most important factors.

What do you learn from this exercise about the way in which the natural environment affects our health?


Health is a large overarching concept. We talk of an individual's health, public health, and environmental health. While the focus of attention is different for each of these, the three concepts are intertwined. They all depend on a number of factors, innate and environmental. Human beings give health a personal and social meaning, a physical and mental meaning. We think of health—of individuals, of society—as an important social goal. The natural environment's role in health—through its effect on our capacity to obtain food, to be secure from extremities of climate, and from natural disasters—was respected by early human beings. But as a species, we have now come to rely more on technology to provide good health. This ranges from mass agriculture to grow and distribute food and supplements to provide full nutrition, to the use of life-maintaining, life saving, and life-extending machinery. We have even turned to technical solutions—anti-depressants, for example—to overcome diseases sometimes caused by lack of good sleep habits and by stress from living in a technological world and by our lack of healthy habits. Thus on the one hand, while technology has helped us rid of various dreaded diseases—smallpox, cholera—it has created new epidemics: heart disease, diabetes, cancer, and depression, for example. And some of today's diseases come from our ignorance and neglect of how the environment affects human health.

While health is the property of an individual, it can also be thought of as a property of a population. Genetics as well as physical, environmental, and socioeconomic conditions determine population health. Average lifespan (or life expectancy), resistance to disease (or incidence rates of disease) and other factors such as birthweight and infant mortality are used as indications of population health.

In these notes, we will focus mainly on the effects of the physical environmental conditions on individual and population health. The ecological, systemic nature of factors affecting health necessitates an understanding of the modification of the environment—by technology, individual pollution, climate change, soil, water, and air quality, migration, and socioeconomic conditions.

Structural changes in governments or other political and economic conditions such as the large scale changes in the former Soviet Union or the numerous localized wars or the globalization and the globally deregulated trade prompted by the World Trade Organization all contribute to population health. These conditions are not considered here in any detail.




  ©Copyright 2003 Carnegie Mellon University
This material is based upon work supported by the National Science Foundation under Grant Number 9653194. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the National Science Foundation.