Positive Health Online

Abstract

VALKONEN and KUUSI, Department of Medicine, University of Helsinki, Helsinki, Finland studied whether the acute atherogenic effects of secondhand cigarette smoke could be prevented by the effective free radical scavenger, vitamin C.

Background

During passive smoking the body is attacked by an excess of free radicals inducing oxidative stress. In nonsmoking people, even a short period of passive smoking breaks down serum antioxidant defence (TRAP) and accelerates lipid peroxidation, leading to the accumulation of their low-density lipoprotein (LDL) cholesterol in cultured human macrophages.

Methodology

Blood samples were collected from nonsmoking individuals (n = 10) as they were consecutively exposed to normal air or cigarette smoke during four separate days. During the last two days, a single dose of vitamin C (3 g) was given, which doubled its plasma concentration.

Results

Vitamin C did not influence the plasma antioxidant defense of the resistance of LDL to oxidation in normal air, but prevented the smoke-induced decrease in plasma TRAP, decrease in the resistance of LDL to oxidation and the accelerated formation of serum thiobarbituric acid reactive substances (TBARS) otherwise observed 1.5 hours after the beginning of passive smoking.

Conclusion

Vitamin C protected nonsmoking subjects against the harmful effects of free radicals during exposure to secondhand smoke.

References

Valkonen MM and Kuusi T. Vitamin C prevents the acute atherogenic effects of passive smoking. Free Radical Biology and Medicine 28(3): 428-36. 1 Feb 2000.