Effects of Cigarette Smoking
We all know the catastrophic effects of smoking. One only needs to read the side of a cigarette pack. But in case you don't have any packs handy, here's what you'll find on packages bought in the United States:
· Smoking Causes Lung Cancer, Heart Disease, Emphysema, And May Complicate Pregnancy.
· Quitting Smoking Now Greatly Reduces Serious Risks to Your Health.
· Smoking By Pregnant Women May Result in Fetal Injury, Premature Birth, And Low Birth Weight.
· Cigarette Smoke Contains Carbon Monoxide.
But there are other, less catastrophic effects, as well as ways to counter these effects. This isn't to say you can take supplements to reduce risks to anywhere near zero, but there are some prudent countermeasures if one can't or won't quit smoking. The various articles below detail some of the effects and countermeasures.
Osteoporosis and Vitamin D
In past studies, it has been shown that cigarette smoking is associated with a reduced bone mass and an increased risk of osteoporosis. However, scientists have yet to explain this observation conclusively. A recent study has attempted to rectify this by conducting a cross-sectional study involving 510 healthy women aged 45-58 years, half of which were current smokers. The results showed that smoking reduced levels of 25-hydroxy Vitamin D and 1,25-dihydroxy Vitamin D by 10%, and levels of parathyroid hormone by 20%. In addition, smokers had a 50% greater incidence of suboptimal vitamin D status compared with non-smokers.
In summary, it can be seen that cigarette smoking has a significant effect on calcium and vitamin D metabolism, which cannot be explained by other lifestyle factors. Moreover, the study is another example of the negative nutritional implications of smoking.
Eur. J Clin. Nutr. 1999, 53;12:920-926.
Atherosclerosis and Vitamin E
Atherosclerosis is characterised by fatty deposits on the inner walls of the arteries. These are caused by the oxidation of low and very low density lipoproteins (LDL and VLDL), which in turn leads to their deposition in the arteries resulting in a gradual narrowing of the blood vessel. Vitamin E is believed to inhibit the oxidation of LDL and VLDL thereby preventing the build up of atherosclerotic plaques. To look at this further, American scientists carried out a two-month trial to examine lipoprotein oxidation in 40 middle-aged Smoking men each supplementing with 200mg of natural Vitamin E daily. Compared to the placebo group, those receiving the active supplement had elevated levels of Vitamin E in their LDL and VLDL. The elevated levels were shown to increase their resistance to oxidation and the likelihood of them "sticking" to the artery walls. This recent evidence reinforces previous work and suggests that smokers may reduce their risk of developing heart disease by supplementing with Vitamin E.
The American Journal of Clinical Nutrition,1998,
Blood Circulation and Vitamin C
Studies have shown that cigarette smoking impairs blood circulation and blood flow from the heart. Recent research suggests that these effects can be reversed by administration of vitamin C. A Swiss team used positron-emission tomography to assess blood flow from the heart. Measurements of blood flow from the heart, were 21% lower in smokers than in non-smokers. Vitamin C infusion normalized blood flow and blood flow reserve of the heart in smokers, but had no effect in non-smokers. Smokers have reduced plasma and tissue concentrations of Vitamin C, so smoking leads to both decreased natural antioxidants and an increased oxidative burden. The researchers suggested that Vitamin C supplementation may prevent coronary heart disease in smokers.
Lancet, 2000, 356, 9234; 1007
Cardiovascular Disease and Cancer
Studies suggest that foods rich in polyphenols (compounds found in fruits and vegetables) might reduce the risk of cardiovascular disease and cancer. In one study green tea was found to be the one of the main dietary sources of polyphenols. The present study investigated the antioxidant effects of Green Tea extract (GTE).
The study included eight smokers and eight nonsmokers. The GTE group had increased plasma antioxidant capacity (most prominently in smokers).
The overall effect of the 10 week period was a decrease in oxidative damage to DNA, blood proteins, and plasma lipids and most importantly there was increased antioxidative defence. Therefore green tea may protect against heart disease due to its protective mechanism against free radical damage to cells and tissues.
Br J Nutr, 2002, 84 (4): 343-355.
More About Vitamins and Smoking
A new study shows that smoking depletes the body of vitamin C, a powerful antioxidant that protects the body from disease. However, the study by Berkeley scientists suggests that moderate supplementation can help smokers boost their vitamin C levels significantly.
Antioxidants such as vitamin C, vitamin E and carotenoids are thought to help the body fight off diseases ranging from cancer to heart disease, and help stave off the degenerative effects of aging.
The study indicates, too, that previous research that found depleted vitamin E and carotenoids in smokers may have been measuring the effect of poor diet, not smoking. The study was designed specifically to separate the effects of diet and smoking on antioxidant levels in the body. "The first piece of advice for smokers is, of course, stop smoking," said study leader Lynn Wallock, a Berkeley scientist. "Barring that, smokers can benefit by improving their diet to include more fruits and vegetables, which contain a balance of antioxidants and other nutritional benefits, like fiber and carotenoids. "Or, they can take vitamin C supplements. Even with modest vitamin C supplementation, smokers can improve their plasma vitamin C levels substantially. However, no regimen of diet or supplementation can make up for the adverse consequences of smoking."
The study was conducted by Wallock, Bruce Ames, professor of molecular and cell biology; Jens Lykkesfeldt, Stephan Christen and Harry Chang of Berkeley; and Robert Jacob of the Western Human Nutrition Research Center. Because nonsmokers with a poor diet showed increased levels of antioxidants in their blood after taking vitamin C and E supplements in the study, the results hint also that supplements can improve the health of those with poor diets. Supplements, however, cannot provide all of the health benefits of fruits and vegetables, Wallock cautions.
The researchers screened hundreds of male volunteers to find smokers and nonsmokers with poor diets, looking specifically for low intake of fruits and vegetables. Anyone taking vitamin supplements was screened out. The reason, Wallock said, is that many previous studies of smokers have not distinguished the effects of smoking from the effects of a poor diet, which is common among smokers. "Smokers tend to have poor diets, so some effects that have been found may not be the result of smoking, but the result of not eating well," she said.
The volunteers selected for the study averaged 2.7 servings of fruits and vegetables per day, as compared to the 5-9 servings recommended by the National Research Council and a minimum of two servings of fruit and three of vegetables per day.
In baseline comparisons between the smokers and nonsmokers, smokers were found to have significantly lower vitamin C levels in blood plasma than did nonsmokers. However, vitamin E, beta-carotene and lycopene levels were not significantly different between smokers and nonsmokers with a poor diet. Lycopene is the major carotenoid found in tomato products, while beta-carotene is found in carrots and other orange or red fruits and vegetables.