Modern lifestyles have made prolonged sitting a health concern. But sedentary behavior itself might not be related to impaired mental health and cognition, according to new research published in Mental Health and Physical Activity.
“Sedentary behavior is currently a hot topic, and it has even been termed the ‘new smoking’ epidemic. Sedentary behavior is said to be associated with several adverse health outcomes, including mental and cognitive health,” said study author Chantal Koolhaas of University Medical Center Rotterdam.
“Most studies examined these associations with sedentary behavior as measured by questionnaire. From previous studies, we knew that objective and subjective measures do not always correspond well.”
“We have unique data on sedentary behavior, since the use of objective devices was not that common in the year that we collected our data. Therefore, we were one of the few with the possibility to examine the association between sedentary behavior and mental health outcomes over time.”
The researchers analyzed data that had been collected during the Rotterdam Study, an ongoing population-based study that has been conducted in The Netherlands since 1990. The study has recruited more than 15,000 subjects aged 50 years or older.
Koolhaas and her colleagues were particularly interested in 1,841 participants who had worn a motion-sensing device called an actigraph for seven consecutive days.
High levels of sedentary time were associated with depressive symptoms, anxiety disorders, and worse cognitive performance — but these correlations disappeared after the researchers controlled for disability, smoking and occupational status.
“Having a disability increases the risk of worse mental and cognitive health and is associated with higher levels of sedentary time. Therefore, in this study, disability was considered a confounder; an antecedent of the exposure (sedentary time) and the outcome (mental and cognitive health), and not on the causal pathway,” the researchers wrote in their study.
“However, it might be argued that prior sedentary behavior had led to disabilities, which in turn led to poor mental health and impaired cognition.”
But in a longitudinal analysis, sedentary behavior was unrelated to depressive symptoms, anxiety, or cognitive performance after a follow-up period of 5.7 years — even when the confounders were not accounted for.
“According to our study, sedentary behavior is not associated with adverse mental and cognitive health over time. This means that a lot of sitting will not necessarily lead to mental health problems,” Koolhaas told PsyPost.
“The use of objective measures ensures that we do not have to rely on the memory of participants when filling out questionnaires and this makes the total sedentary measure more accurate,” Koolhaas continued.
“However, such device cannot distinguish different types of sitting. It might be that specific types of sitting are differently associated with mental and cognitive health. It would be very interesting to examine the association with objective and subjective sedentary behavior in the same sample, at the same time.”
Though it might not harm your mental health, previous studies have shown that higher levels of sedentary behavior are linked to various diseases, including cancer, diabetes, and heart disease.
“Sedentary behavior is not the new smoking, but undoubtedly it is important to be physically active, especially when (prolonged) daily sitting is inevitable,” Koolhaas concluded.
The study, “Objectively measured sedentary time and mental and cognitive health: Cross-sectional and longitudinal associations in The Rotterdam Study“, was authored by Chantal M. Koolhaas, Frank J.A. van Rooij, Desana Kocevska, Annemarie I. Luik, M. Arfan Ikram, Oscar H. Franco, and Henning Tiemeier.
