Table 4. Antioxidant Activity Levels Within Groups And Between Groups.

	Smokers		Non-smokers
Variables	n	Antioxidant activity (μmol/l)	n	Antioxidant activity (μmol/l)	p-value*
NCF group	12	2.4 ± 0.5	28	2.7 ± 0.7	0.070
SCF group		2.7 ± 0.6		2.7 ± 0.3	0.938
p-value*	27	0. 072	13	0.752

*Mann-Whitney U-test.