A new study finds that people smoking over 20 cigarettes in a day may get vision disorders. A study on the effect of tobacco on the vision of a smoker was published in the journal Psychiatry Research in January 2019.
The study, co-authored by Rutgers researcher, Steven Silverstein, shows that heavy smokers might have a high risk of vision loss. It was conducted on two groups of varied people. First, 71 healthy people who consumed less than 15 cigarettes in their entire life. The second group was of 63 smokers who consumed more than 20 cigarettes in a day.
The second group so selected, included people who were heavy smokers and made zero attempts to quit smoking in their life ever. Also, both groups included people from the age group of 25-45. As measured by standard visual acuity charts, the participants had normal or corrected-to-normal vision.
Researchers installed a 19-inch cathode-ray tube monitor and made the participants sit at least 59 inches away from it to conduct the study. The monitor displayed stimuli and researchers tried to understand how the participant discriminated between contrast levels while studying their both eyes.
The results so obtained, signaled major changes in the smokers' red-green and blue-yellow color vision. This leads the researchers to deduce that neurotoxic chemicals, such as those in cigarettes, can cause vision loss or vision disorders. Another finding showed that the ability to discriminate between the contrast and colors was less in the second group of people as compared to the first group.
Co-author of the study, Steven Silverstein, said, "Cigarette smoke consists of numerous compounds that are harmful to health, 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 added, "Previous studies have pointed to long-term smoking as doubling the risk for age-related macular degeneration and as a factor causing lens yellowing and inflammation.”
According to Fact Sheet 2018 India published by the World Health Organization, tobacco killed about 1 million (10 lakh) people in the year 2018 in India. This was about 9.5% of the total number of deaths in the country in that year. Also, the mean age when people start smoking in India is 18.7 years.
Silverstein suggested that the further studies in this regard would include people with schizophrenia or other visual disorders. Under this category, both smokers (along with their smoking rate) and non-smokers should be assessed.
Though the study did not land readers to a physiological explanation for the findings, Silverstein said that nicotine and smoking would surely affect blood vessels and neurons in the retina of the eye because of their effects on one’s vascular system.