But most people have very little idea of exactly how dangerous smoking can be, how many different types of diseases it can cause or complicate, or how much smoking increases the risk of contracting various deadly diseases.
The principal substances causing cancer are found in the "tar." And smoking is also responsible for many other types of cancers, many of which prove fatal:
- cancers of the mouth and throat
- lung cancer
- oesophageal cancer
- bladder and kidney cancer
- pancreatic cancer
- stomach cancer
- liver cancer
- cervical cancer
A smoker increases the risk of getting lung cancer by 900 percent (10 times), and a heavy smoker increases the risk over 1400 percent (15-25 times the risk).
- Two immediate effects of smoking on heart and circulation are
These responses are caused by nicotine which acts on the nervous system, causing the heart rate to rise and blood vessels to constrict. This narrowing of the blood vessels causes the blood pressure rise and strain is put on the heart.
- an increase in your heartbeat rate,
- a sharp rise in blood pressure.
- The carbon monoxide in cigarettes depletes the oxygen carrying capacity of a smoker's blood. This means that the heart has to pump harder to get enough oxygen to the rest of the body.
- Smoking can also affect the blood in the long term: increase in the blood cholesterol and fibrinogen levels. Both these factors mean blood will clot more easily and this will increase the risk of having a heart attack, caused by a blood clot forming in the heart.
- The heart and circulation attacks caused by smoking include : Coronary heart disease (CHD), Aneurysm, Peripheral vascular disease (PVD), stroke etc.
Pulmonary and Respiratory Diseases
- Smoking causes the accumulation of harmful substances inside the bronchial tubes. The obstruction of small airways in the lung prevents inhaled air from exit, leading to final rupture of the air sacs, causing breathing difficulties. This disease is called emphysema. Patients need to use breathing mask because most lung cells are damaged.
- Other common smoking related disease is chronic bronchitis, which has similar symptoms as emphysema.
Cigarette smoking can affect women's fertility, men's fertility, sexual function, pregnant women's health and the health of unborn and young children:
- Women who smoke may have reduced fertility. Studies found that 38% of non-smokers conceived in their first cycle compared with 28% of smokers. Smokers were 3.4 times more likely than non-smokers to have taken more than one year to conceive.
- It was estimated that the fertility of smoking women was 72% that of non- smokers.
- Cigarette smoking can also affect male-fertility; spermatozoa from smokers are found to be decreased in density and motility compared with that of non-smokers.
- A new study found that sperm cells carrying Y-chromosome are more vulnerable to the toxins in cigarette smoke.
- Smoking may cause impotence, or penile erection dysfunction in the male smokers.
- Studies suggest that the risk of impotence for smoking men aged 31-49 years old was 1.5 times higher than non-smokers. Smoking men aged 40-70 years old are twice as likely as non-smokers to develop moderate or severe impotence.
- For younger women, smoking and the use of oral contraceptives increase the risk of a heart attack, stroke or other cardiovascular disease by tenfold.
- This effect is more marked in women over 45.
- Babies born to women who smoke are on average 200 grams (8 ozs) lighter than babies born to comparable non-smoking mothers. Low birth weight is associated with higher risks of death and diseases in infancy and early childhood.
- The more cigarettes a woman smokes during pregnancy, the greater the probable reduction in birth weight.
- Recent research suggests that cigarettes can reduce the flow of blood in the placenta which limits the amount of nutrients that reach the foetus.
- The rate of spontaneous abortion (miscarrage) is substantially increased in women who smoke by tenfold.
- Moreover, smokers have more complications of pregnancy and labour which include bleeding during pregnancy, premature detachments of the placenta and premature rupture of the membranes, and inadequate milk production.
- Perinatal mortality (defined as still birth or death of an infant within the first week of life) is increased by about one-third in babies of smokers.
- Infants of parents who smoke are twice as likely to suffer from serious respiratory infection than the children of nonsmokers.
- Smoking during pregnancy can also increase the risk of asthma in young children ( before 1-year-old) by 2.8 times.
- Other disorders associated with smoking in pregnancy include an increased risk of infantile colic and cleft palate.
- Smoking in pregnancy also have implications for the long term physical growth and intellectual development of the child, such as reduced height, lower attainments in reading and mathematics.
- The natural menopause occurs up to two years earlier in smokers.
- The likelihood is related to the number of cigarettes smoked, with those smoking more than ten cigarettes a day having an increased risk of an early menopause.
Increased risks for many sickness
- Chemicals in tobacco cause damage to the macula (the most sensitive part of the retina, the back of the eye). Tiny blood vessels can burst through the macula, leading to irreversible damage.
Skin and hair
- Just 10 minutes of cigarette smoking decreases oxygen supply to body and skin for almost an hour.
- Smoking robs the skin of collagen which keeps the skin elastic.
- Smokers get more and deeper wrinkles all over their faces because nicotine constricts the tiny capillaries that nourish the skin. Smokers in their 40s often have as many facial wrinkles as non-smokers in their 60s.
- Smoking interferes with the healing process, it takes longer to heal and there is more scarring.
- Smokers are also prone to premature thinning and graying of the hair. Men who smoke are twice as likely to become bald as are men who do not smoke, and premature graying is 3 to 6 times more common in smokers.
Muscles and Bones
- Smoking delays the healing of fractures, and in some smokers bone healing is indefinitely delayed.
- Women with a smoking history have significantly lower bone density and are much more likely to suffer fractures. Furthermore, their earlier menopause add to the risk of osteoporosis. Studies show that women who use tobacco have a 50% higher risk of osteoporosis than nonsmokers.
- Smokers also have poorer muscle strength, agility and balance