Smoking cigarettes, cigars, pipes or any type of tobacco causes physical changes in the body. While some of the effects of smoking can't be seen for years, other signs of cigarette smoking can be observed within days, if not minutes, of the last cigarette. Some of the signs are overt while others may be less obvious.
Finding tobacco or paraphernalia in the person's possession or on his property may appear to be an obvious clue that the person is smoking. However, while finding actual cigarettes, lighters, matches or pipes can mean that a person is smoking, it is not definitive. Other reasons may exist for having possession of tobacco or accessories.
Finding evidence of cigarette smoking may be a more clear sign. Ashes in a car or ashtray, cigarette butts or burn marks may be a stronger indication that the person is smoking.
Smokers experience the effects of tobacco in their appearance and presence. According to MayoClinic.com, smoke immediately gets in a person's hair and clothing, causing the person to smell like tobacco. Cigarette smoke quickly causes the breath to smell bad. After a period of time, teeth and fingernails begin to turn yellow or brown. Cigarette smoking narrows the arteries that lead to the head, causing pallor and an unhealthy appearance. Eventually, cigarette smoking causes wrinkles, a raspy voice and often a hacking cough.
According to a 2010 study in the journal "Addictive Behaviors," while some people smoke to self-medicate or improve mood, some teenage smokers may actually experience an increase in depression. According to Jennifer O'Loughlin, a professor at the University of Montreal Department of Social and Preventive Medicine, people who used cigarettes to enhance mood had a higher risk of experiencing depression than people who never smoked.
Nicotine and other tobacco constituents also have an effect on brain circuitry, according to a 2007 study published in "Nicotine & Tobacco Research," the official journal for the Society for Research on Nicotine and Tobacco. People may exhibit fewer attention-deficit symptoms after smoking cigarettes.
Smokers who don't want to be found out may act suspicious and become easily startled or angered. According to TeenDrugAbuse.us, teen smokers may act more aggressive or abrasive. They may become more willing to partake in other addictions. Smokers who become addicted may plan their day around when they can smoke and may become irritable if they can't have a cigarette. According to MayoClinic.com, smoking can decrease energy levels and may reduce the desire for previously enjoyable activities.