More than 80% of the people who smoke cigarettes began to smoke
before the age of 18. About 5% started smoking at age 8, and another 20%
started before age 13.1
Nicotine is only one of more than 4,000 chemicals in tobacco, but it
is the major component that acts on the brain. The lungs readily absorb
nicotine from cigarette smoke. The tissues of the mouth can also absorb nicotine when smoking cigars or pipes, or when tobacco is
chewed.
Nicotine reaches the brain within seconds and has a direct effect on
the body for up to 30 minutes. When a person uses tobacco regularly, the levels
of nicotine accumulate in the body during the day and persist overnight,
exposing the person to the effects of nicotine for 24 hours.
In the body, nicotine acts as both a
central nervous system stimulant and sedative. The
person immediately feels the stimulant effect and pleasurable sensation. It
increases alertness, relaxes muscles, improves memory and attention, and
decreases irritability. The stimulant effect causes a sudden increase in blood
pressure, breathing rate, and heart rate. The central nervous system
stimulation is followed by depression and fatigue, causing the person to want
another cigarette.
Nicotine is one of the most addictive substances. Some teens show
early signs of addiction within days to weeks after starting to smoke. Repeated
tobacco use causes a need for increasingly large amounts of nicotine to feel
the same effect (tolerance) and
withdrawal symptoms if the person tries to quit.
Smoking affects a person's appearance by causing bad breath, yellow
teeth and fingernails, and wrinkles. Tobacco also leads to serious health
problems, including:
- Long-term (chronic) cough, shortness of breath,
and wheezing.
- Increased risk for heart disease, lung and other
cancers, stroke, and
emphysema.
- Increased risk among women for
having babies with a low birth weight, which may result in the death of the
baby. Women who smoke are also at risk for menstrual problems, early menopause,
and
osteoporosis.
- Increased risk among men for
erection problems.
Signs of use
- Cigarette odour on
clothing
- Cigarette or other tobacco product packages or wrappers in
wastebaskets
- Sudden need for a teen to go outside or to the
bathroom after meals
- Decrease in appetite
Strawberry-, cinnamon-, orange-, or chocolate-scented cigarettes
called bidis, beedies, or beadies have become popular with teens in some areas. These cigarettes are made in India and are shaped like
marijuana joints. They are unfiltered and have a 28% higher nicotine
concentration than regular cigarettes.