Abstract

Background: Smoking is among the established yet modifiable risk factors for cancers, cardiovascular diseases, and pulmonary disorders. Oxidative stress has been proposed as a key mechanism mediating the deleterious consequences of smoking. The present study evaluated the effect of supplementation with Chlorella vulgaris, a nutrient and bioactive green microalgae with proven antioxidant capacity, on the burden of oxidative stress in Iranian smokers. Methods: Thirty-eight smokers (mean age: 37.11 +/- 1.69 years; females: 18.4) were administered C. vulgaris extract (3600 mg/day) for a period of 6 weeks. Fasted serum samples collected at baseline and after the completion of study were analyzed for the concentrations of vitamin C, vitamin E, glutathione, and malonedialdehyde (MDA) as well as activities of superoxide dismutase, glutathione peroxidase, and catalase. Total antioxidant capacity of serum was also determined by the ability of serum to inhibit the formation of ferryl myoglobin radical species. Results: Six-week supplementation with C. vulgaris extract in smokers was associated with marked elevation of all assessed serum antioxidant measures (p < 0.001) and significant reduction of MDA levels (p = 0.002). After gender segregation, a similar pattern of changes was observed for both male and female subjects apart from lack of significant change in serum vitamin E status in females. Although the magnitude of change in serum vitamin E was significantly greater in males compared to females (p = 0.014), there was no significant change in the magnitude of changes for other assessed parameters between the genders. Conclusions: Supplementation with C. vulgaris extract significantly improves antioxidant status and attenuates lipid peroxidation in chronic cigarette smokers. Hence, C. vulgaris might prevent the disease burden and mortality rate associated with smoking.