Combined association of physical activity and diet with C-reactive protein among smokers

BACKGROUND: In the general population, both physical activity and dietary behavior are independently associated with less systemic inflammation, with this relationship less examined among smokers. To our knowledge, no study has examined the combined association of both physical activity and dietary behavior on systemic inflammation among daily smokers, which was the purpose of this study. METHODS: Data from the 2003–2006 NHANES were employed. 810 adult smokers provided C-reactive protein data (CRP; a marker of inflammation), and sufficient physical activity (accelerometry) and dietary data (healthy eating index). RESULTS: The fully adjusted model showed that participants meeting physical activity guidelines and eating a healthy diet (β = −0.34, p = 0.03) had lower CRP levels when compared to those not engaging in these health behaviors, but only having one health behavior was not a significant predictor of CRP (β = −0.19, p = 0.14). CONCLUSIONS: Smokers engaging in regular physical activity while consuming a healthy diet demonstrate lower CRP levels than their counterparts. When taken together, these behaviors may mitigate inflammation associated with various chronic diseases, which is of particular importance as very few smokers successfully quit smoking.