More specifically, a higher sedentary time and ‘passive commuting,’ which the researchers defined as commuting that is not on foot or bicycle, was associated with vitamin D deficiency.
“Further studies are needed to establish causality of this association and the effect of vitamin D deficiency in different diseases in this population,” the researchers wrote, adding that the current results suggest “mode of commuting and sedentary time seems important variables related to vitamin D deficiency.”
The researchers, associated with the University of Granada in Spain and various universities in Chile (Universidad Andrés Bello, Universidad Católica del Norte, and Pontificia Universidad Católico de Valparaíso), published their results last month in the journal Nutrients.
According to them, data from a general Chilean population regarding vitamin D levels are scarce, hence the novel results may add key information for public policy in Chile related to health systems.
“In this sense, lifestyle recommendations are needed in order to establish specific recommendations, since the patterns of physical activity and sedentary time could affect differentially vitamin D status according to age,” they added.
A generational difference
The researchers looked at data from the 2016-2017 Chilean National Health Survey, which included 2,233 participants representative of the entire Chilean population over 14 years old from the country’s 15 regions, both urban and rural.
“This survey represents the first, largest, and representative measurement of serum vitamin D levels in Chilean people,” the authors explained. During the data collection process, participants visited labs, where nurses took venuous blood samples in morning hours to measure vitamin D status.
Additionally, participants filled out qustionnaires relating to their physical activity and mode of commuting.
For this cross-sectional study, the researchers extracted data of 1931 women, 1245 of which were in the 18-65 age range, and the remaining 686 aged 65 and older.
“Interestingly, active adult women and inactive older women share the same [vitamin D status] value, as well as inactive adult women correspond to active older women, creating a mirror effect,” they reported.
Additionally, the authors contrasted the results to similar studies in Europe. “The prevalence of vitamin D insufficiency [in Chile] was higher in young people compared to older participants,” they said, which was contrary to trends in European countries as observed by the 2017 Food4Me study published in the European Journal of Nutrition.
The available data is insufficient to offer a causation, but the researchers postulated that in Chile’s case, it might be because the older population is healthier and “quite more active than younger participants.”
“These differences are connected, in some cases, to institutionalization factors, especially combined with concurrent health and mobility problems, such as reduced skin efficiency to produce endogenous vitamin D levels, poor dietary vitamin D intake as well poor general nutritional status,” they added.
Published online, doi:10.3390/nu11020300
“Passive Commuting and Higher Sedentary Time Is Associated with Vitamin D Deficiency in Adult and Older Women: Results from Chilean National Health Survey 2016–2017”
Authors: Patricio Solis-Urra, et al.