After adjustment for potential confounders , individuals in the calcium ( -3.1 1.3 , P < .05 ) , vitamin D ( -3.1 1.3 , P < .05 ) , and joint calcium-vitamin D groups ( -3.4 1.3 , P < .05 ) had greater reductions in serum TNF - concentrations compared with placebo ( 0.1 1.2 ) .