By David Mendoza - Wednesday, January 28, 2015

At the end of last year, the Centers for Disease Control and Prevention (CDC) released its tally of the number and leading causes of deaths for 2013. The fatality count nearly topped 2.6 million. Diseases of the heart and cancer killed the most people, accounting for 46% of all deaths. Compared to 2012, age-adjusted death rate for these two diseases decreased only slightly.

Click here to embiggen this GIF.

However, cancer and heart diseases were not the leading causes of death among all age groups. Using data from the National Vital Statistics System, I made the GIF above which shows that remarkable differences emerge between what kills young and old Americans when divided into 5-year increments. Younger Americans die disproportionately from preventable causes like accidents. The share of deaths caused by accidents peaks among those in their early twenties, making up 42% of the 19,006 deaths of people between 20 and 24 years of age. The two overall leading causes of death — heart disease and cancer — made up only 8% of those deaths. Cancer and heart diseases only begin to eclipse everything else after Americans reach their mid-forties. Cancer predominates between the ages of 45 and 80 and as Americans reach the century mark, they start to die primarily from diseases of the heart.

The chart on the lower half of the GIF shows the total number of deaths in each age group. It illustrates how many more old people die than young people. This explains why cancer and heart diseases can be the overall leading causes of death yet not be the most common cause of death for young people.

Why this is important

Despite the fact that cancer and heart diseases kill substantially more people than other diseases or causes, a Gallup poll from last year found that 17% of Americans thought the Ebola virus — which killed 2 people in the U.S. in 2014 — was the third “most urgent health problem facing this country at the present time.” Cancer and heart disease, on the other hand, polled at 10% and 2%, respectively. This is a classic example of the availability heuristic, which states that people reach inaccurate conclusions when they rely only on the most conspicuous data. In this case, the threat that Ebola posed to Americans received an excessive amount of coverage from American journalists and politicians — despite the fact that it’s a ridiculously hard disease to catch and the crisis is still primarily concentrated in West Africa.

In order to accurately evaluate the risk certain diseases present to us, we need to pay more attention to the numbers and less to the hype.