Smoking is widely recognized as unhealthy due to graphic warnings on cigarette packets and media reports linking it to cancer. However, less known is the connection between smoking and mental illness. Recent research has shown a strong link, though it remains debated whether smoking causes mental disorders or if it alleviates existing symptoms. Nonetheless, Canadian researchers have demonstrated greater clarity on this issue.
Center for Quantitative Genetics and Genomic at Aarhus University’s Doug Speed and colleagues demonstrated that smoking can lead to bipolar disorder and depression. Speed said that statistics indicate that smoking causes mental illness. He added that although smoking might not the only cause of mental illness it dos increase the risk of hospitalization by 250%.
Smoking linked to mental disorders
To investigate the link between smoking and mental disorders, Doug Speed and his team required substantial data. Mental disorders have multiple potential causes, so it was crucial to account for other influencing factors. They obtained access to the UK Biobank, a massive repository with genetic information from over 500,000 individuals. This genetic data was combined with extensive health records and lifestyle information provided by participants.
The researchers utilized computer analysis to identify patterns in data related to the correlation between smoking and mental disorders. Their approach introduces a novel perspective by considering the temporal aspect of the issue. Past studies overlooked the fact that people usually start smoking before the age of 20, while hospital admissions for mental disorders occur between the ages of 30 and 60 on average.
Nicotine causes imbalance in serotonin production
Smoking is statistically linked to mental disorders like depression, bipolar disorder, and schizophrenia, but researchers lack a definitive explanation and rely on several theories to understand this connection.
Doug said that researchers are still looking for a biological connection between smoking and mental disorders. According to one theory, nicotine may hinder absorption of serotonin which is a neurotransmitter that when in low levels can lead to depression. When one smokes, the nicotine triggers serotonin production which makes someone feel relaxed but continued use can inhibit production of the neurotransmitter leaving one upset, unstable and anxious.
