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The use of the word "channel" can mean two things in the context of an anti-smoking campaign: Television channels, or route through which to convey the message (in effect, television or radio ads, billboards on busy streets, etc.). Consequently, the following will provide recommendations utilizing both meanings.
Because smokers in their 30s and up are more likely to be addicted to nicotene and other chemicals used in the manufacture of cigarettes, and because they are more likely to be resistant to changing a habit that is addictive, the goal is usually to stop people from smoking before they start. Hence, the emphasis is on the young.
As far as the optimal "channel" for an anti-smoking campaign, demographic studies by marketers would indicate that television geared toward teens and young adults would be the most effective use of resources. Television networks like MTV, Spike TV, WB, UPN and others that target these age groups, and which enjoy high visibility among those groups, would be the highest priority for allocation of marketing resources, along with radio stations known to be popular with teens and young adults.
Similarly, advertising in magazines enjoyed by these age groups is another effective means of conveying the message that smoking is dangerous. Finally, given the enormous role that social networking and Facebook play in the life of the average teenager, advertising on such "pages" would reach millions of the target audience.
Given the factors the lead young people to take up smoking, including peer pressure and symbolic rejection of societal values, any marketing campaign has to be well-thought-out. As the goal is to persuade impressionable individuals from making decisions that could harm them many years down the road, and given the countervailing pressures to conform, visible images of the effects of smoking are more effective than nonvisual messages. The success of tobacco companies in appealing to new generations, however, is illustrative of the scale of the challenge any such marketing campaign would face.