(Image source from: www.healthline.com)

While excessive smoking can lead to various health issues, including cancer and heart disease, a new study has found that smoking more than 20 cigarettes a day can cause blindness.

The study, carried out by Rutgers University, noted that chronic tobacco smoking can have harmful effects on “spatial and color vision”.

The findings, published in the journal Psychiatry Research, stated significant changes in the smokers’ blue-yellow and red-green color vision. This proposes that consuming substances with neurotoxic chemicals, such as those in cigarettes, may lead to total loss color vision.

Heavy smokers as well have reduced the ability to discriminate contrasts and colors compared with non-smokers.

The study was conducted on who were in the 25-45 year age group.

“Our results indicate excessive use of cigarettes, or chronic exposure to their compounds, affects visual discrimination, supporting the existence of overall deficits in visual processing with tobacco addiction,” said Steven Silverstein from the Rutgers’s Behavioral Health Care.

“Cigarette smoke consists of numerous compounds that are harmful, and it has been linked to a reduction in the thickness of layers in the brain, and to brain lesions, involving areas such as the frontal lobe, which plays a role in voluntary movement and control of thinking, and a decrease in activity in the area of the brain that processes vision,” he said.

For the study, the team examined 71 healthy people, who smoked less than 15 cigarettes in their whole lives and 63 people, who smoked more than 20 cigarettes in a day.

The study’s findings showed noticeable changes in the red-green and blue-yellow color vision of heavy smokers.

Former studies had also pointed to long-term smoking as doubling the risk for age-related macular deterioration and as a factor causing lens yellowing and inflammation.

-Sowmya Sangam