However, compared to PT commuters, car drivers ate more fruits and were overall more physically active. These results are compatible ISRIB with the American Time Use Survey (ATUS) which shows that daily commute tends to squeeze the time dedicated to other essential activities such as exercise, food preparation,

and sleeping (Basner et al., 2007 and Christian, in press). A transportation survey conducted every year since 2007 in the study target population at Queens College has consistently shown that the median commute time of car drivers is 60 min, per day, versus 120 min for PT users (Morabia and Zheng, 2009). In a scenario in which car drivers commute in 1 h, and PT users in 2 h, ATUS predicts that the PT commuters will lack 2.2 min of exercise, 1.4 min of food preparation, and 15.6 min of sleeping per day (Christian, in press). The reduction click here of exercise time seems too modest to explain the present study results, but a compounded loss of 16.4 min per day in health-related activities (− 5.2% for a two-hour commuter compared to a one-hour commuter) may make a difference. Thus, the time saved by car drivers in their commute can be allocated to health-related activities and may explain a higher adherence to physical activity guideline in car drivers than in

PT commuters. We explored differences in inflammatory response across commute modes because it is a plausible short-term effect of the type of moderate physical activity involved however when commuting using PT. Physical activity can stimulate anti-inflammatory cytokine production,

such as IL-1ra, IL-4 and IL-10, while sedentary behaviors can generate an excess of pro-inflammatory cytokines, such as IL-1, TNF and chemokines (Colbert et al., 2004). However, we did not find differences in CRP and WBC between two commute modes. Cytokine balance may be under epigenetic regulation (Backdahl et al., 2009). DNA methylation is an epigenetic event that may contribute to cancer and other human disease occurrence by altering gene expression. Global hypomethylation, as indicated by low levels of LINE-1 methylation, has been associated with genome instability and elevated cancer risk, whereas methylation in the promoter region of specific genes is associated with gene silencing. Methylation patterns can be influenced by environmental factors such as diet, (Zhang et al., 2011b) physical activity, (Bjornsson et al., 2008, Coyle et al., 2007 and Zhang et al., 2011a) and air pollution (Miller and Ho, 2008). In this study, we did not find that commuting modes affected the methylation levels of LINE-1 or IL-6 promoter.