Smoking and low antioxidant levels increase oxidative damage to sperm DNA

Our previous studies have shown that men with low ascorbate intake have markedly increased oxo(8)dG in the DNA of their sperm. Because cigarette smoke is high in oxidants and depletes plasma and tissue antioxidants, oxidative DNA damage in sperm and tocopherol and ascorbate levels in seminal plasma were determined in smokers and non-smokers. The level in sperm DNA of oxo(8)dG, an oxidative lesion of guanine, was 50% higher in smokers compared to non-smokers (p = 0.005). The concentration of cr-tocopherol in seminal plasma was decreased in smokers by 32% (p = 0.03). Smoking and low antioxidant levels increase oxidative damage to sperm DNA. We discuss the possibility that paternal smoking causes mutations in sperm that lead to cancer, birth defects, and genetic diseases in offspring.