Comparisons between FD and PD revealed significant differences in changes of serum MDA ( -0.540.82 mol/l vs. +0.171 mol/l , P < 0.001 ) , GSH ( +8.440.1 ng/l vs -13.129.4 ng/l , P = 0.002 ) and TAC ( +0.140.43 mmol/l vs. +0.020.45 mmol/l bovine serum albumin equivalent , P = 0.03 ) .