The New York Times
Cataracts are the leading cause of blindness in the world, and are often related to aging. In a common form of cataracts, proteins in the lens change over time, developing chromophores — molecular add-ons that absorb color in the blue part of the spectrum. Chromophores reduce the amount of light reaching the retina (and give the lens a yellow-brown appearance), but they also disrupt the structure of the lens proteins, causing light to scatter.