Sitting For More Than 3 Hours A Day Increases Mortality Risk

The American Cancer Society has released a study which shows that not only does decreased physical activity increase the risk of death, but this risk is also affected by the amount of time which is spent sitting. This length of sitting time was independently associated with a person's total mortality regardless of their physical activity level. The public health guidelines focus on giving information regarding increasing physical activity, but don't seem to offer information regarding decreasing sitting time.

The research

The researchers conducted the study by analyzing survey responses by people who were not known to suffer from diseases such as heart attacks, cancer, stroke or any chronic lung diseases. The study was done using information collected between 1993 and 2006. The following important findings were noted:

• The results showed that leisure time which was spent sitting was associated with an increased mortality rate especially in women.
• Women who reported that they would spend more than 6 hours sitting every day were 37% more likely to die, during the time period of the study, than women who spent fewer than 3 hours sitting per day.
• It was also discovered that men who sat for more than 6 hours a day were 18% more likely to die, in the study period, than those who spent less than 3 hours sitting per day.
• It's important to note that these results remained unchanged when physical activity levels were factored into the findings.
• There was a greater association of prolonged sitting time with cardiovascular disease mortality than cancer mortality. The association was even stronger when there was a lack of physical ability in the respondents.
• In the worst case scenario it was reported that men and women who sat more and were less physically active were 48% and 94% more likely, respectively, to die in the study period as compared to those men and women who sat the least and were the most physically active.

The reason behind these findings could be that prolonged sitting, despite the person's activity level, results in important metabolic consequences. This can have a negative effect on cholesterol, triglyceride levels, high density lipoproteins (HDL), fasting glucose levels, leptin and resting blood pressures in a person.

READ Sitting Is Killing You - What You Can Do About It?