How does tobacco make you feel?
The nicotine in tobacco smoke travels quickly to the brain,
where it acts as a stimulant and increases heart rate and breathing. Tobacco
smoke also reduces the level of oxygen in the bloodstream, causing a drop in
skin temperature. People new to smoking are likely to experience dizziness,
nausea and coughing or gagging.
The mood-altering effects of nicotine are subtle, complex
and powerful. Some people feel that smoking helps them to be alert and to
concentrate, and also that it helps them to feel relaxed. Research has shown
that smoking raises levels of dopamine, a chemical in the brain, increasing
feelings of pleasure and reinforcing the desire to continue to smoke.
Smoking and second-hand smoke can irritate the eyes, nose
and throat. Tobacco smoke may cause headaches, dizziness, nausea, coughing and
wheezing, and can aggravate allergies and asthma. Smoking also weakens the
sense of taste and smell, reduces hunger and causes the stomach to produce
How smoking affects you depends on:
- how much and how often you smoke
- how long you’ve been smoking
- your mood, expectations and the environment
- your age
- whether you have certain pre-existing medical or psychiatric
- whether you’ve taken alcohol or other drugs (illicit,
prescription, over-the-counter or herbal).
How long does the feeling last?
When a cigarette is smoked, the effects are felt in less
than 10 seconds, and last only a few minutes.
Is tobacco dangerous?
Yes. Tobacco use is the primary cause of preventable disease
and death in Canada,
and is considered our greatest public health concern. One study estimated that
more than 45,000 Canadians die each year of smoking-related causes. This
includes people who smoke, and people who are exposed to second-hand smoke.
When tobacco is burned, a dark sticky “tar” is formed from a
combination of hundreds of chemicals, including poisons that cause cancers and
bronchial disorders. Tar is released in tobacco smoke in tiny particles that
damage the lungs and airways and stain teeth and fingers. Tar is the main cause
of lung and throat cancers. (Although nicotine is the main ingredient of
tobacco that causes addiction, it is not known to cause cancer.)
Burning tobacco also forms carbon monoxide (CO), a poisonous
gas you can’t see or smell. When smoke is inhaled, CO replaces oxygen in red
blood cells. While nicotine speeds up the heart, making it work harder, CO
deprives it of the extra oxygen this work demands. This is one way that smoking
contributes to heart disease.
When swallowed, nicotine is extremely toxic. Ingesting about
40 milligrams of pure nicotine, or roughly the amount contained in two
cigarettes, is fatal. However, when a cigarette is smoked, most of the nicotine
is burned, and only one to four milligrams is absorbed into the body.
Similarly, the amount of nicotine absorbed from the patch, and other methods of
nicotine replacement therapy used to help people quit smoking, is well below
Canadian laws require that levels of tar, nicotine and
carbon monoxide appear on cigarette packages. It was once thought that
cigarettes with less tar and nicotine might be less harmful. However, research
has shown that so-called “light” cigarettes are just as likely to cause disease.
Is tobacco addictive?
Yes. Once a person begins to smoke, particularly at a young
age, the chances of becoming addicted are quite high. People new to smoking
quickly develop tolerance to the initial ill effects, and if they enjoy the
stimulant and pleasant effects, they may begin to smoke regularly. Those who
smoke regularly tend to have a consistent number of cigarettes per day.
Canadians who smoke have, on average, about 15 cigarettes per day.
Nicotine addiction involves psychological and physical
factors. Psychological factors may include feelings of pleasure and alertness.
People who smoke regularly may learn to rely on the effects of nicotine to
bring about these feelings. They also develop conditioned signals, or
“triggers,” for cigarette use. For example, some people always smoke after a
meal, while working at a certain task or while in certain emotional states,
such as feeling depressed or anxious. These triggers lead to behaviour
patterns, or habits, which can be difficult to change.
Signs of physical dependence include the urge to smoke
within minutes of waking, smoking at regular intervals throughout the day, and
ranking the first cigarette of the day as the most important.
People who are addicted to nicotine may become tolerant to
the desired effects. They may no longer experience pleasure from smoking, but
continue smoking due to cravings and to avoid nicotine withdrawal.
Symptoms of nicotine withdrawal include irritability,
restlessness, anxiety, insomnia and fatigue. These symptoms vanish within a
couple of weeks. Some people may be unable to concentrate, and have strong
cravings to smoke, for weeks or months after quitting smoking.
What are the long-term effects of using tobacco?
The risk of long-term effects increases with the amount smoked,
and the length of time a person smokes.
- is the main cause of lung cancer
- increases the risk of cancers of the colon, mouth, throat,
pancreas, bladder and cervix
- causes most cases of chronic bronchitis and emphysema
- causes smoker’s cough
- is a major cause of heart disease and stroke
- increases the risk of medical problems for a woman during
pregnancy (e.g., miscarriage, bleeding, placenta previa and poor healing) and
increases the risk that her baby will be underweight or will die in infancy
- causes osteoporosis (thinning of the bones)
- increases risk of digestive problems
- affects the immune system, making people who smoke more
prone to colds, flu and pneumonia
- decreases the amount of vitamin C in the body, which may
cause skin wounds to heal less quickly
- can cause the arteries in the legs to become clogged,
resulting in poor circulation, leg pain, gangrene and loss of limb.
Many of the risks and dangers of smoking also apply to
people who are exposed to second-hand smoke. Long-term exposure to second-hand
- has been linked to heart disease and cancer
- (in pregnant women) increases the risk of complications
during pregnancy and delivery, and of delivering babies with a low birth weight
- (in young children) has been linked to sudden infant death
syndrome, can lead to or worsen respiratory problems such as asthma; also
causes middle ear infections.
Use of tobacco products that are not smoked, such as snuff
and chewing tobacco, are linked to an increased risk of oral cancers, gingivitis
and tooth decay.
After a few years, people who quit smoking can generally
achieve the same health levels as those who have never smoked, especially if
they stop while they are young. Quitting smoking can take several attempts, so
it is important to keep trying. Stop-smoking aids containing nicotine, such as
the patch, gum, inhaler, lozenge or nasal spray, can help to ease withdrawal
symptoms and reduce cravings. Such aids work best when the person is highly
motivated to quit, and when the person has other supports, such as family,
friends, a stop-smoking group or telephone support.
Certain medications that do not contain nicotine can help
people to quit smoking. These include bupropion (Zyban) and varenicline
(Champix). Both are available by prescription.
For some people, cutting down before quitting helps to
lessen the withdrawal symptoms, and allows them to change their smoking
behaviours gradually. Strategies for cutting down include delaying cigarettes,
smoking fewer cigarettes and smoking less of each cigarette. Although cutting
down may reduce some health risks, there is no safe level of smoking; cutting
down is not an alternative to quitting.
There are currently more former smokers than smokers in
Canada. In 2005, 39 per cent of the population, or more than 10 million Canadians
aged 12 and over, reported they had quit smoking.
Copyright © 2003, 2010 Centre for Addiction and Mental Health