As we age, the lenses in our eyes become cloudy, obscuring our vision. That's what the folks in the lab coats call cataracts - and it's a common phenomenon. Cataracts affect more than 20.5 million Americans over 40. How can you tell if you have cataracts? It's a gradual process, so you may not notice any symptoms until the cataract is severe enough to distort light as it enters your eye. Early symptoms include blurriness and needing more and more light to read, even while wearing glasses. As they develop and worsen, cataracts may also interfere with the ability to perform basic activities like driving and reading.