What is an indicator of excessive cigarette use?

Brown discoloration of fingers serves as a clear indicator of excessive cigarette use due to the nicotine and tar in cigarette smoke. These substances can cause staining of the skin, particularly on the fingers of individuals who frequently handle cigarettes. Over time, this discoloration becomes more pronounced, signaling a long-term habit of smoking.

In contrast, the other options do not correlate with excessive cigarette use. For instance, increased appetite is typically not associated with smoking, as many smokers experience a decrease in appetite. Enhanced lung function would not occur with excessive smoking; instead, tobacco use generally leads to declining lung health. Lastly, excessive smoking tends to increase stress levels rather than reduce them, as many smokers use cigarettes as a coping mechanism for stress, but this often creates a cycle that may result in increased anxiety or stress over time. Thus, the discoloration of fingers is the most telling sign of a high level of cigarette consumption.