Smoking
Smoking is as bad for the eyes as it is for the rest of the body. [5] If you smoke, you can develop serious eye conditions that can cause vision loss or blindness. Smoking causes changes in the eyes that can lead to vision loss. Smokers significantly increase their risk of developing a cataract compared with non-smokers. Studies show that people who smoke double their chances of developing cataracts, and the risk continues to increase with the degree of smoking.
Obesity
Obesity can cause the formation of cortical cataracts, a condition where light is scattered by a defective lens. The adipose tissue present in excess weight releases a chemical called leptin, which triggers oxidative stress that can damage the eye.