Smoking and Accelerated Aging
Aging is exactly an accumulation of biochemical damage and the resulting disarray caused by that damage. We all know that smoking is bad for you, but it seems that smoking causes some of the same effects as one of the genetic conditions that causes accelerated aging: "Smoking can accelerate the aging process and shorten the lifespan by an average of more than 10 years. We focused on what happens within the lungs because of the similar aging effects, including atherosclerotic diseases and cancer, seen in people with Werner's syndrome and people who smoke ... Werner's syndrome involves a genetic mutation that causes a deficiency in what's known as Werner's syndrome protein. The protein normally helps repair DNA damage. Smoking does not appear to cause the same mutation, but our study showed that it does decrease Werner's syndrome protein ... The team also applied cigarette smoke extract to cultured lung fibroblasts taken from nonsmokers. They saw that Werner's syndrome protein expression was decreased, and the cells had lost their ability to repair wounds. In contrast, when the team caused the lung fibroblasts in petri dishes to overexpress Werner's syndrome protein, it had a protective effect and helped resist the damaging effects of cigarette smoke."
Link: http://www.scienceblog.com/cms/effects-smoking-linked-accelerated-aging-protein-18505.html