Applied Social Psychology Understanding and Managing Social Problems

Introduction

The societal burden of unhealthy behaviours

When a baby is born, we can estimate the expected number of years the new individual will live. This life expectancy is calculated based on statistics regarding how long people in a given population usually live and is considered an important indicator of health and illness in populations. During the past 40 years, life expectancy has increased all over the world (Table 10.1), although more in some regions than in others. Besides the number of years people live, one can calculate the number of healthy years in a person's life. The at-birth expected number of healthy years of life ranges from about 40 years in African countries to about 70 years in developed countries (Mathers et al., 2004).

Although the increase in life expectancy is a good sign, many factors continue to threaten health and life expectancy. In developing and in developed countries, different factors threaten life expectancy. In developing countries (e.g., African countries, Afghanistan, Haiti, Philippines) the relatively low life expectancy is largely determined by a high child mortality rate, often related to infectious diseases, poor housing, and malnutrition. Most of the factors that underlie the high child mortality rate are more strongly determined by structural factors such as economic policy and the quality of the healthcare system than by individual behaviour. In developed countries (e.g., European countries, Canada, USA, Australia), life expectancy is largely related to lifestyle factors, such as smoking tobacco and dietary choices, as these are important causes of cancer and cardiovascular disease. Thus, as countries become more developed, the lower their child mortality rate, and the more life expectancy is determined by individual behaviours.

Smoking tobacco is one of the greatest behavioural threats to human health. It is related to several types of cancers, to heart disease, and to chronic lung disease. One in two smokers will die from smoking. On average smokers live 7 years less than non-smokers and also they live more unhealthy years. Worldwide, about 1.1 billion people smoke, representing about one-third of the population aged 15 years and older. About 3 million smokers die each year from smoking.