Vit. C may cut passive smoking damage

Vitamin C may help prevent the damage caused by passive smoking, offering a way for people to protect themselves from smoke, according to recent research. Researchers from the University of California, Berkeley, USA, did a study with 67 non-smokers who were exposed to environmental smoke. The results showed that those who took 500 mg of vitamin C daily had lower levels of a compound linked to the damage done by tobacco smoke. The study pointed out that vitamin C may help protect non-smokers from the oxidative damage caused by second-hand tobacco smoke. Oxidative damage was compared to rust damaging metal. This is caused by charged particles known as free radicals, and can be counteracted by antioxidants including vitamin C. But what works in a laboratory does not always hold true in the human body. The researchers tested for levels of F2-isoprostanes, which are generated through a form of oxidative stress called lipid peroxidation. This can damage the cell membrane and help form plaque that blocks arteries. The 67 participants, all non-smokers exposed to second-hand smoke, were randomly assigned to one of three groups. One group took 500 mg of vitamin C a day, a second group took vitamin C, vitamin E and the antioxidant alpha-lipoic acid (ALA), and a third group took daily placebo capsules.

After two months, blood levels of F2-isoprostanes dropped by 11.4 percent for the vitamin C group compared with those taking the dummy capsule, and 12 percent for the vitamin C plus E plus ALA group. It was found that adding vitamin E and ALA did not help much. The participants were told not to take any other vitamins for several weeks before the study started, and people who reported eating plenty of fruits and vegetables were excluded. The evidence is overwhelmingly consistent that people who eat a lot of fruits and vegetables have a lower risk of cancer since such people may already have so many antioxidants in their system that they would not benefit from taking vitamins.

The findings should not lead people to think that they can pop vitamins and escape the consequences of unhealthy habits. Rather, if one is in a situation where one cannot escape frequent exposure to second-hand smoke, it may be worthwhile to take vitamin C supplements as a precaution. And, as always, eating a diet rich in fruits and vegetables would help.