Tobacco is the only freely available product which, when used as intended, kills every second person using it.
Because of its transient effects on the brain, smoking tobacco formed part of religious ceremonies in South America as far back as 5000BC. The tobacco plant was introduced to France in 1560 by Jean Nicot (after whom Nicotine is named): this reached America by 1612, and by the end of the century smoking had reached every major civilization of the time. Today, there are an estimated 1 250 000 000 smokers worldwide.
A cigarette is said to contain more than 4000 chemicals, 60 of which are known to cause cancer. Apart from the actual tobacco, there is the filter and the paper, which is treated with chemicals so that it doesn’t burn but smoulders slowly. These chemicals are also inhaled, at high temperatures, when you smoke. All these substances are responsible for the health problems caused by smoking.
The other important substance in cigarettes is nicotine: though it also has physical effects, it does not cause the lung damage or the cancers. But nicotine is highly addictive so the smoker keeps on smoking, and thus keeps inhaling the toxins which do the damage.
Within ± 10 seconds of being inhaled, nicotine reaches your brain, where it acts on receptors causing the release of a hormone called Dopamine, also known as “the pleasure hormone”. Like the nicotine, the dose of dopamine is short-lived : to recreate the pleasant effect, another dose of nicotine is needed. In addition, the smoker becomes used to dopamine, and eventually needs a larger amount to get the same pleasant effect as before and will also smoke more often to avoid the unpleasant effects of being without dopamine in his circulation. By this stage true nicotine addiction is established. Adding menthol to tobacco increases the effect of the nicotine, making it even more addictive.
Initially, small doses of nicotine are stimulating, increasing alertness, pulse rate and blood pressure. As smoking increases, the higher dose of nicotine causes mild sedation, which is why many smokers will light up to calm themselves when under stress.
Besides lung cancer, continued smoking has other effects on the body, and can lead to stiffened, narrowed arteries, raised cholesterol, osteoporosis, blood clots, strokes and heart attacks, and on average, reduces lifespan by 15 years.
The risk of lung cancer is proportional to the total lifetime consumption of cigarettes (one pack year equals 365 packs of cigarettes) and to the intensity at which they were smoked. So a person smoking 30 cigarettes daily for 5 years has a higher cancer risk than a person smoking 5 cigarettes daily for 10 years.
Another substance inhaled when smoking is carbon monoxide (as found in car exhaust fumes): this binds strongly to haemoglobin in red blood cells preventing oxygen from being absorbed. Smokers thus deprive their whole body of adequate oxygen. Because the cigarette is kept burning, the smoke inhaled is hot and dry and this irritates and dries out all the airways from the lips, nose and sinuses, down to the smallest parts of the lungs. This constant irritation and heat exposure triggers increased mucus production and decreases the respiratory tract’s resistance to infection.
SMOKING AND WOMEN
Male smokers have three time the risk of heart attack compared to non-smokers, but the risk for a woman who smokes is six time greater.
Smoking affects fertility, reducing a woman’s chance of conceiving by ± 40%. Smoking during pregnancy has many affects on the baby: nicotine causes arteries to constrict, which reduces the blood supply to the baby. In addition, the carbon monoxide inhaled by the mother decreases the amount of oxygen available in that reduced blood supply, leading to chronic oxygen shortage for the baby. This greatly increases the risk of an underweight baby, preterm birth and even stillbirth.
Babies born to mothers who smoke have three times the risk of Sudden Infant Death Syndrome (cot death) and may be more susceptible to asthma in childhood. Learning disorders, lower IQ’s and behavioural problems are also more frequent, and thought to be due to the chronic oxygen shortage before birth cause by the mother’s smoking. Whilst not as severe as in smoking, inhaling second-hand smoke can have a similar negative effect on the unborn babies of pregnant women.
Nicotine is also found in the breast milk of smoking mothers who are thus feeding their babies nicotine several times a day: the baby will have no choice but to suffer the effects of nicotine on its body simply because its mother smokes.
HOW TO STOP
Quitting smoking is one of the best decisions you could ever make for yourself and for people you care for. Smoking is more than just a chemical addiction: there are associated behavior patterns and triggers (social, emotional etc) which must be dealt with at the same time.
Medication is available to help with curbing the desire to smoke, and to minimize withdrawal effects. Studies show that the best results are obtained using medication with a support system which can include group meetings, e-mail support, even psychologist input for behavior modification if needed. On average, three months is needed to fully break the habit.
Within 48 hours of your last cigarette, nicotine & carbon monoxide is cleared from your circulation and your taste buds start to re-awaken. By one month, your face looks clearer, and your lungs become able to clear out the accumulated mucus with effective coughing. By the third month, unless your lungs have been damaged by smoking, the coughing/wheezing subsides, and within a few years your cigarette-related risk of heart attack and lung cancer will be halved.
Smoking in history…
• 1912 the first concerns were raised that cigarette smoking might cause lung cancer
• 1938 statistics linked smoking to an increased risk of premature death
• 1966 smoking was shown to cause a gene mutation causing cells to become cancerous.
- Copyright Dr Anna Hall