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,
68; 5:1034-41.
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.
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