We spend a great deal of time worrying about things, turning to Dr Google to asks about our risks of terrorism or homicide or cancer.
But a new study has laid bare that our hypochondria may be slightly misplaced: most of us fret over some rare killers, while ignoring the biggest and most likely threats, such as heart disease.
To lay bare this disparity, undergraduate students at the University of California, San Diego, compiled graphs on the leading causes of death in the US and the top Google searches about death.
The analysis revealed that cardiovascular disease is far and away the biggest danger facing Americans, but the vast majority are disproportionately worried about terrorism, despite its very low mortality rates.
The irony, public health experts say, is that the public’s fixation on unlikely causes of death means we are less likely to worry about or act on very real threats – which could make it even more of a risk.
Students from the University of California at San Diego set out to see if the public attention given to causes of death was similar to the actual distribution of deaths. The average percentage for 13 leading causes of death between 1999 and 2016 are shown above
Actual mortality rates were compared with Google data indicating how much the public searched for each cause, the rates for which are shown in the table above
For the project titled Death: Reality vs. Reported, four students in a computational science class at UC San Diego asked three questions:
- How do people die?
- How do people think we die?
- Is there a difference?
To answer those questions they compiled a list of the top 10 most common causes of death from 1999 to 2016 according to Centers for Disease Control and Prevention data.
They also included an additional three items that received a lot of public attention: terrorism, opioid overdose and homicides.
The statistics were then cross-referenced with data from Google Trends beginning in 2004 that show what kinds of things people were worried about dying from.
They students got the idea for the project from a 1979 study that looked at how often different causes of death were covered by news outlets compared with the how often people died from each.
‘We set out to see if the public attention given to causes of death was similar to the actual distribution of deaths,’ the authors said on the project website.
‘After looking at our data, we found that, like results before us, the attention given by news outlets and Google searches does not match the actual distribution of deaths.
‘This suggests that general public sentiment is not well-calibrated with the ways that people actually die.
‘Heart disease and kidney disease appear largely underrepresented in the sphere of public attention, while terrorism and homicides capture a far larger share, relative to their share of deaths caused.’
An analysis of Google trends revealed that the number one cause of death feared by Americans was cancer, making up 36 percent of searches.
Heart disease, meanwhile, made up less than two percent of searches, indicating that Americans are unaware of how dangerous the disease is.
Comparing that to real risk, Americans were right and wrong.
Across the 17-year period studied, cancer and heart disease were the two leading causes of death, making up for more than half of total deaths each year.
In 2016 cancer was responsible for 26 percent of deaths and heart disease for 26.5 percent.
Meanwhile, the rate of deaths from terrorism was effectively zero – in 2016 fewer than 100 Americans died from terrorism compared with 1.2 million who died from cancer or heart disease. Thus, it doesn’t appear as a real risk on the graph.
However, despite having a death rate of almost zero, terrorism came in at number five with 7.2 percent of searches.
Looking at the fear-risk ratio for terrorism over time, the researchers found it has fluctuated, but there has always been a disproportionate amount of fear. While the mortality rate for terrorism stayed consistent at next to zero, the percentage of searches yo-yoed from 10 percent in 2004 down to 3.5 percent in 2012 and back up to seven percent in 2016.
Suicide was also found to have six-times its relative share compared to the actual death rate at 12 percent.
The rate of deaths from Alzheimer’s also increased significantly from two percent in 1999 to almost five percent in 2016, while the rate of Google searches for the disease stayed consistent at three percent. The increase has commonly been attributed to a growing number of aging adults and the fact that doctors are now more likely to list Alzheimer’s as cause of death than they were two decades ago.
The six leading causes of death in the US are heart disease, cancer, lower respiratory diseases, car accidents, stroke and Alzheimers. The average rate for each between 1999 and 2016 according to the CDC is shown in the graph above
The remaining categories were all found to be relatively close to their actual rates.
The next causes behind cancer and heart disease were lower respiratory diseases, such as asthma and bronchitis, and car accidents at six percent each, and stroke at four percent. The remaining four were diabetes at three percent and kidney disease, pneumonia and suicide at two percent.
One of the most notable changes in actual cause of death was with overdose. In 1999 overdoses were responsible for less than half a percent of deaths in the US.
By 2005 that number had doubled to one percent and by 2013, commonly seen as the year that the opioid crisis began, it had risen to 1.8 percent.
In just three years by 2016 it had risen to 2.5 percent. That year life expectancy in the US dropped for the first time since 1993, which is thought to be in part because of opioid overdoses. By contrast, the proportion of Google searches on overdoses dropped steadily across the 12 year period from 2.6 percent in 2004 to 1.3 percent in 2016.
Why worrying over things that can’t be prevented is so bad for your health
The CDC considers at least seven of the 13 causes of death to be preventable including cancer, heart disease, stroke, lower respiratory disease, diabetes, suicide and overdose.
Some of the most important risk factors for many of those conditions are body weight, diet and physical activity.
One-third of cancer deaths, 80 percent of heart disease and stroke deaths, and 90 percent of diabetes deaths could have been prevented, according to previous research.
Lifestyle changes such as eating a healthy diet and exercising have been found to cut the risk of death from these causes down significantly.
However, the Google trends revealed that people paid an disproportionate amount of attention to causes such as car accidents, terrorism and homicide which are much more difficult for the average person to prevent.
Similarly news coverage was found to be heavy on deaths from those causes that aren’t preventable.
The students concluded that if more the public shifted its attention away from unpreventable things that amount for less than 10 percent of deaths overall, the rates for the more prominent causes could drop.
Along with the ten leading causes of death, the researchers included CDC data from three causes that receive a lot of public attention: homicide, above in red, overdose, in purple, and terrorism, which cannot be seen because the rate is next to zero
The graphs above show the percentage of Google searches on homicide, overdose and terrorism from 2004 to 2016