- Too much sitting time is problematic, especially in low- and lower-middle-income countries, a new study suggests.
- Clinicians should focus on less sitting and more physical activity as a low-cost intervention with great benefits.
- But individuals also need to assess their lifestyles and take their health seriously, researchers say.
We sit more than ever today, and experts over the years have shown us why this matters. From raising our risk of heart disease, diabetes, obesity, and stroke, our body has several kinds of negative reactions to a sedentary lifestyle.
Studies to date arguably centred on data from affluent countries, leaving researchers wondering whether prolonged sitting has the same consequences in low- and middle-income countries.
New international research now has some answers: According to the study, which involved 31 researchers and more than 100 000 people across 21 countries, those in poorer parts of the world tend to suffer the most perilous effects of sedentary behaviour.
Measuring physical activity
Reporting their findings in the journal JAMA Cardiology, the authors explained: “In this cohort study including 105 677 participants from 21 countries, higher sitting time was associated with an increased risk of all-cause mortality and major cardiovascular diseases (CVD), and the association was more pronounced in low-income and lower-middle–income countries.”
The participants, aged 35 to 70 years, were studied from January 2003 to August 2021. The researchers measured their daily sitting time using the International Physical Activity Questionnaire (IPAQ) – a self-reported measure of physical activity comprising a set of four questionnaires.
Higher amounts of sitting time were linked to an increased risk of mortality and CVD across all the populations studied, but this relationship was more evident in low-income countries, such as Bangladesh, India, and Zimbabwe.
“The overarching message here is to minimise how much you sit,” co-author, professor Scott Lear, a Simon Fraser University health scientist, said in a news release.
Heart disease, premature death
According to the paper, sitting for six to eight hours a day increases the relative risk of heart disease and premature death by around 12 to 13%, compared to people who sit for less than four hours per day.
The relative risk increased to 20% for participants who sat up to eight hours or more per day.
Not only does the newest research on this popular topic show how extensive sedentary living is, but it takes one step further by laying bare the role that poverty plays in all of this – although, unless future studies are carried out, it’s challenging to say why this difference in association exists.
However, this discrepancy might be partly explained by the different patterns of sitting behaviours across different income levels, the team suggested.
They explained: "That is, television viewing time is more common among people with lower socioeconomic positions and showed a stronger association with outcomes, compared with other sitting behaviours, perhaps owing to coincident poor nutrition habits and prolonged and uninterrupted sedentary patterns."
What to do
On the bright side, there are World Health Organization recommendations for physical activity that could effectively reduce this risk of high sitting time, the researchers say.
"If you must sit, getting in more exercise during other times of the day will offset that risk,” said Lear, adding:
Lear emphasised the findings that a combination of sitting and inactivity accounted for around 9% of all deaths, which is pretty close to the percentage of deaths caused by smoking (10.6%).
“It’s a global problem that has a remarkably simple fix. Scheduling time to get out of that chair is a great start,” he said.