It has been called the most dangerous consumer product in the world -- causing the deaths of 5 million people a year. The World Health Organisation has warned that by 2020, it will become the biggest killer of people in the developing world. In the United States, it's already been classified as addictive as heroin.
But over a billion of us continue to smoke tobacco. Why? Is it through ignorance of the possible dangers or peer pressure? Is it because it's enjoyable or because big tobacco companies encourage people to do it? The Big Question: Why do people smoke?
What answers does the tobacco industry have? Emma Joseph visits the second largest licensed tobacco company in the world - British American Tobacco . Last year, it produced 800 billion cigarettes in 180 countries. BAT's chief scientist, Chris Proctor, says his business is not unhappy that people choose to start smoking and acknowledges that it is very hard to quit. But he says there is no one reason why people start. He says for many, it is all down to peer pressure, for some, it is a matter of rebellion. For him, smoking is a small pleasure.
The anti-tobacco lobby blames glossy adverts for the growing number of smokers reported by various studies into cigarette use. BAT's Chris Proctor says it is not that simple. He says BAT has very strict marketing standards and points out that Scandinavian countries banned cigarette advertising in the 1970s, but the number of smokers, especially among the young, is no different to places where advertising is allowed.
How big is the tobacco industry?
The global tobacco market is worth fifteen billion US dollars a year and the World Health Authority (WHO) - who have made tobacco a global health priority - estimates that by the year 2030 there will be 2 billion smokers worldwide - many of them in the developing world. In Kenya, for instance, nearly half the adult population smokes tobacco.
So why do people in Kenya smoke? The Big Question went to find out.
Abdullahi Ali Isaq is a 22 year-old student who lives in Korogocho slum on the outskirts of the Kenyan capital, Nairobi. He is so worried about the effects of tobacco consumption there he carried out his own research into smoking in Kenya and posted it on the net.
What impact does smoking have in the developing world?
Many people in Korogocho earn less than a dollar a day, but they can end up spending most of that on a single packet of cigarettes. The WHO estimates that over three quarters of the world's smokers live in the developing world. In some households, tobacco consumption accounts for 10% of expenditure. In poor communities, this can have a serious impact on their ability to buy basics like food and clothing - creating a firm link between poverty and tobacco .
How harmful are cigarettes?
Smoking is one of the most dangerous habits in the world. Every day, more than 13,000 people die from smoking related diseases. At the Aga Khan hospital in Nairobi, Dr Paul Wangai has seen an alarming rise in tobacco-related diseases - diseases that are new to Kenya, like gum disease, cancer of the larynx, emphysema, lung cancer and heart attacks. But for many Kenyans, treatment for these conditions is prohibitively expensive.
Why do people continue to smoke?
Professor Peter Odhiambo is the Chairman of Kenya's National Tobacco Free Initiative Committee (NTFIC). According to him, tobacco companies don't do enough to warn people about the dangers of smoking. He says too many people become addicted to cigarettes at an early age. A recent survey by the NTFIC found that 70 percent of smokers said that they could not kick the habit.
This edition of The Big Question was first broadcast on 3rd July 2004
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