This one is pretty straightforward. As well as increasing the risk of lung cancer, heart disease, stroke, diabetes, obesity, and hypertension, studies have shown that smoking cigarettes more than doubles your chance of developing cataracts and AMD later on in life. The odds of developing these and other age-related eye conditions decrease significantly once you quit smoking, but don't use this as an excuse to procrastinate. There's no better day than today to start living a healthier life.