Nate Berg is a freelance reporter and a former staff writer for CityLab. He lives in Los Angeles.
New research suggests who you see may subtly affect your life expectancy.
A typical walk down the street will probably put you into visual contact with other people. You may not talk to them or know them or even recognize them, but these people may have an impact on your life and the choices you make. Who these people are – and more importantly how old they are – may be guiding your own perceptions of how long you think you'll live.
And how long you think you'll live may affect how long you'll actually live, influencing the decisions you make.
Drawing this connection is a new study out of Newcastle University published in the journal Human Nature. The researchers were trying to understand why people in lower socioeconomic situations tend to make the decisions that are reflective of shorter life expectancies – early reproduction, less effort in health promoting activities, a "present-oriented" rather than a long-term time perspective.
"It seems that, under conditions of socioeconomic deprivation, psychological mechanisms for adjusting personal allocation of time and energy tend to become calibrated to a shorter personal time horizon," the researchers write. "Within affluent developed societies, people of lower socioeconomic position engage in a suite of behaviors which make sense if their lives are going to be relatively short."
One reason, they suggest, is that the people living in neighborhoods of lower socioeconomic standing have less visual contact with older people. They argue that a direct source of information about local life expectancy comes not from hearing about people who've died, but from seeing the people around them who are still alive – who's walking around on the streets, who's in the shops, what types and ages of people make up what the researchers have dubbed the "social diet" of a neighborhood. They argue that people growing up in lower socioeconomic situations have a social diet consisting of fewer older people, which feeds back into their own perception of life expectancy.
Their study area was two different neighborhoods in Newcastle upon Tyne, England. Though very similar in terms of layout, population size and density and other demographics, one is among the top 25 percent of richest neighborhoods in England, while the other is in the poorest 1 percent. Researchers performed a number of walks throughout these neighborhoods, noting the estimate ages of every person they saw on the street. About 2,500 people were observed overall.
A the chart below shows, adults over 60 were observed far more in the richer neighborhood (A) than in the poorer neighborhood (B).
By comparing the ratio of people 60 and over observed by those in their prime reproductive ages – the 20-39-year-olds – the researchers calculated that the perceived likelihood of a 20-39-year-old living to 60 and beyond is 71 percent in the richer neighborhood and just 37 percent in the poorer neighborhood.
But according to census figures, there are actually more people aged 60 and older in the poorer neighborhood than in the richer one. So while younger people should be seeing more older people in their neighborhood, they aren't. The researchers suggest that this may have a chronic effect of younger people, giving them the impression that they won't likely be around long enough to be an old person shuffling down the street because there aren't any old people shuffling down the street.
The researchers concede that these results are based only on two neighborhoods and can't be taken to represent the way the world works as a whole. But it does open up an avenue for further study to try to better understand what sort of psychological effects result from who you see on the street. The people around you may be determining your life path in ways you can't even notice.
Image credit: Flickr user Ed Yourdon