If you smoke cigarettes, your sense of smell may not be as good as it should be. Smokers have more trouble identifying odors than nonsmokers do, and about twice as many smokers as nonsmokers have a reduced sense of smell. Smoking affects the sense of smell in both young people and older ones.
The sense of smell is more important than you may realize. Much of the flavor of food actually comes from its smell, rather than its taste. People who can't smell don't enjoy their food as much as other people do. The sense of smell is also important for safety. For example, people with an impaired sense of smell would be less able to detect the odor that is added to natural gas (the kind of gas used in gas stoves) to alert people to gas leaks.
Fortunately, though, the sense of smell may improve after a person quits smoking.