More than 12 million adults age 40 and older suffer from vision impairment, according to the Centers for Disease Control and Prevention. That number is expected to double by 2050 as baby boomers get older. “Visual acuity deteriorates for many of us as we age,” says Gregg Ratkovic, president of Medicare at eHealth, an online insurance marketplace. “That’s normal, and that’s what vision insurance is [for].”