mokers have depressed levels of certain antioxidant in their plasma. Theory suggests this is because the free radicals in cigarette smoke deplete the antioxidants, which may subsequently increases the risk of diseases such as cancer. However, a study published in the British Medical Journal in 19961 showed that this is quickly reversed. In the study, 182 subjects were randomly assigned to either a stop smoking or continue smoking group, and as they progressed through the study their plasma vitamin C levels were measured. Four weeks after the baseline measurements were taken, the stop smoking group had plasma vitamin C levels that had increased by a mean of 23.3 %, compared to just 9.8 % in the placebo group. After 26 weeks the stop smoking group had plasma vitamin C levels that were 21 % above their baseline levels. A increase of 25 % of plasma vitamin C has been estimated to require 200 mg/d supplementation with vitamin C. Therefore the rise was most likely due to decreased depletion of antioxidants.
RdB
