The behaviours and factors that threaten longevity

Most people hope for a long, healthy life. And researchers across many disciplines are continually seeking new information on ways to extend the human life span. In a 2020 study published in the journal Proceedings of the National Academy of Sciences (PNAS), researchers examined a wide variety of risk factors related to life expectancy. They identified 57 social and behavioural elements that contribute to an increase in early mortality.
They ultimately pinpointed six factors that have the most impact:
- smoking,
- alcohol abuse,
- lack of physical activity,
- economic/financial difficulties,
- social adversity, and
- negative psychological characteristics.
They say these predictors can be used to understand individual mortality risk, and we need to step back and look at why some first world countries are doing so poorly in terms of life expectancy, says study co-author David Rehkopf, associate professor of medicine at Stanford University. “What you are doing right now matters for your health, it is never too late to begin to be healthy.”
The study, which was based on 13,611 adults ages 50 to 104 who died between 2008 and 2014, didn’t analyse every possible adverse component, but the data give an indication of specific childhood and adulthood factors associated with a reduced life span.
“Social factors and conditions come out as important for mortality, and they are factors that we should pay more attention to,” Rehkopf says.
A healthy life expectancy is defined as the number of years a person at a given age can expect to live in good health. To that end, we spoke with experts in each of the six main categories to determine potential interventions and solutions in order for people to live their longest, healthiest lives.
Smoking

According to the PNAS study, current smokers and those with a history of smoking had the greatest risk of early mortality. The latest data on smoking from the Centers for Disease Control and Prevention (CDC) support this finding on a grand scale, which includes secondhand smoke. Smokers die approximately 10 years sooner than non-smokers. The high concentration of nicotine in cigarettes drives an addiction in the brain that has a massive impact on the lungs and heart. Smoking not only causes lung damage, it weakens the immune system, causing further infections.
“The chemicals in cigarettes result in a constant attack on the lungs,” says Dr Panagis Galiatsatos, assistant professor at Johns Hopkins School of Medicine and a pulmonary and critical care doctor. In addition to cancer, smoking can cause many interstitial lung diseases (ILD), including respiratory bronchiolitis (RBILD) and pulmonary langerhans interstitial lung disease (PLCH), as well as chronic obstructive pulmonary disease (COPD) (which includes emphysema), and pneumonia.
“If people who actively smoke get a viral or bacterial infection, they have more severe symptoms,” says Dr Galiatsatos. “SARS-CoV-2 and Covid-19 are worse in people who smoke.”
Smoking: What you can do

Dr Galiatsatos says to keeps the definition of a smoker simple: “Either you smoke or you don’t.” Severity depends on a brand’s nicotine and tar concentrations, the burn rate, and whether a smoker deeply inhales or gets just a few puffs in before putting it down.
“People ask, ‘Am I a mild, moderate or super smoker?’ I don’t know. It’s the way your body responds,” says Dr Galiatsatos. “It’s like playing Russian roulette. Every time you do it, you expose yourself to dire outcomes. You may smoke once a week; that can still result in cancer. Someone else may have the genetics that even if they smoke daily, they won’t get cancer. You don’t want to play those odds.” (Smoking marijuana or e-cigarettes may pose the same risks around infection and cancer development.)
Dr Galiatsatos says dependence on tobacco is a disease “no different from diabetes … you have to manage it.” As the co-author of new guidelines for smoking cessation, he recommends smokers first surround themselves with people who can empathise. Second, they should talk to a healthcare professional to determine if medical intervention is necessary. Finally, understand that quitting takes time.
“The nicotine replacement therapy patch works, but all have a variable impact of when they’ll work.” Generally, a former smoker is someone who has established six months or more without smoking, while independence is 10 years of not smoking.
Discover 15 mind-blowing ways your body heals when you quit smoking.