Researchers have suggested that prolonged sitting as well as sleeping for too little or too long should be added to a list of lifestyle factors that can increase a person's risk of an early mortality.
They believe that unhealthy lifestyle habits are behind a third of deaths and hope the findings will encourage more people to make small changes to their lifestyles which could, in the long run, help them stay healthier for longer.
Researchers from the University of Sydney studied data from more than 230,000 adults aged 45 and over.
Over a period of six years, they found that those who exhibited any of the lifestyle risk behaviours such as smoking, high alcohol intake, physical inactivity, poor diet, prolonged sitting, and short/long sleep duration were at risk of an earlier death than those who did not.
Meanwhile those who exhibited all six negative habits were five times more likely to die than those with healthier lifestyles.
They also found that those whose lifestyle combinations involved physical inactivity, sedentary behaviour and sleeping for too long were at the same risk of early death as those who smoked and had a high alcohol intake.
"To examine specific patterns of lifestyle risk behaviours, 96 variables - representing all possible mutually exclusive combinations of smoking, high alcohol intake, physical inactivity, poor diet, prolonged sitting, and short/long sleep duration - were created," said Dr Melody Ding, from the University of Sydney, according to the Mail Online.
"Short and long sleep durations were separated as two different risk factors, as their associations with mortality may be explained by different mechanisms.
"This analysis investigated four established and two [new] risk factors, namely, prolonged sitting and unhealthy sleep duration, which may be added to behavioural indices or risk combinations to quantify health risk."
The research was published in the journal PLOS Medicine.
It's not the first time sleeping and sitting behaviours have been associated with an early death. Earlier this year, a study by Warwick University found that sleeping for more than eight hours every night could increase your risk of an early death by up to a third.
They also discovered that people who sleep too little - less than six hours each night - have an increased risk of dying earlier in life.