Effects of Habitual Caffeine Intake, Physical Activity Levels, and Sedentary Behavior on the Inflammatory Status in a Healthy Population

Low-grade chronic inflammation is associated with many chronic diseases and pathological conditions. The aim of the present study was to determine the effect of regular caffeine intake, physical activity levels, and sedentary behavior on the inflammatory status in healthy participants. In total, 112 men and 132 women aged 18 to 55 years and belonging to the staff and student population of the University of the Balearic Islands volunteered to participate in this descriptive cross-sectional study. Plasma concentrations of pro-inflammatory and anti-inflammatory markers were measured. Weight, height, and body composition (bioelectrical impedance) were determined. Caffeine intake, physical activity levels and sitting time, and diet quality were determined using questionnaires. Statistical regression analysis showed that caffeine intake was a negative predictor of C-reactive protein (CRP) (p = 0.001). Body fat percentage was positively associated with CRP (p < 0.001) and inversely associated with adiponectin (p = 0.032) and interleukin (IL)-10 levels (p = 0.001). Visceral fat was the main predictor for IL-6 (p < 0.001) and tumor necrosis factor (TNF)-α (p < 0.001). Sitting time was found to be the main, inverse, predictor for IL-10 (p < 0.001), and a positive predictor for TNF-α (p < 0.001). In conclusion, regular caffeine consumption induced very limited anti-inflammatory effects. Sedentary behavior and body fat accumulation induced significant pro-inflammatory effects.