Mr Epidemiology: Today, I’m welcoming Lindsay Kobayashi to the blog. You can find out more about Lindsay at the end of this post.
As epidemiologists, we are concerned with uncovering the factors in populations that determine who gets sick, who stays healthy, who lives, and who dies. Human life is inherently social, and looking toward our societies and geography can help explain who is healthy or sick, and why. “Location, location, location” is a mantra that rings true with respect to life expectancy. In Canada and the United States, men can expect to live to 79 or 76 years, respectively, while women can expect to live over 80 years (1). The story is similar for most wealthy and developed countries. By contrast, take Afghanistan or any one of several sub-Saharan African countries, where a baby born today could expect to live only until his or her mid-40s or 50s(1).
Temporarily setting aside biologic limitations on health (a loaded issue for another blog post), human-made health limitations clearly exist in our world. A person’s life chances greatly depend on where he or she is born and lives and some people do not reach the same level of health achievable by others. Inequities in life expectancy exist within countries as well: Canada-wide, women residing the poorest neighbourhoods live two years less on average than women residing in the richest neighbourhoods, and this difference is four years for men(2). This striking inequity brings us back to the original question: What determines health?