Benjamin Franklin famously wrote “in this world nothing can be said to be certain, except death and taxes.”

Franklin was a legendary intellect, and it’s hard to overstate the impact he had. But I’d suggest an addition to that particular quote, one with which I suspect he’d agree.

Most of us know him as one of the Founding Fathers, as the author of Poor Richard’s Almanack, as the guy who flew kites during lightening storms. Perhaps less famously, Franklin was also an inventor. He is credited with the creation of the bifocal lens, reportedly inspired by his frustration with switching between pairs of glasses.

As a woman of a certain age, who has needed corrective lenses since childhood, I can well appreciate that frustration, and in turn, that invention! Our eyes are complex organs. In the very front, there is the clear dome of the cornea. Then we have the iris, the colored part of the eye. This is a muscle, and it controls the size of the pupil, the black central hole through which light is allowed entry. From there, light strikes the lens, which is pulled into different shapes by small muscles around its edge, and focused onto the retina in the very back of the eye. Specialized cells in the retina convert light to electricity, and the optic nerve transmits these messages to the brain.

When I talk to my middle aged patients about symptoms they may be having, they frequently volunteer that they now need glasses for the first time, or that they have “upgraded” to those bifocals. They are usually surprised when I reassure them that this is not only normal, but frankly expected! The cells that create the lens loose the ability to repair or replace themselves over time. The lens becomes less flexible. It doesn’t change shape as easily, and as that happens the eye has a harder time focusing up close. Eventually, a person develops presbyopia: age related far-sightedness.

This same process leads to a condition quite familiar to most people: cataracts. As those cells in the lens deteriorate, they become increasingly cloudy. Light has a harder time penetrating, and it may be scattered on the way through, instead of sharply focused. People may notice blurry vision, muted colors, glare around lights. They may need brighter light to read, and find it very difficult see at night. By 80, approximately 50% of people either have cataracts, or have had cataract surgery.

Presbyopia and cataracts may be a normal, readily treated part of aging, but you shouldn’t neglect those eye exams. As we get older, other eye conditions become more common. Diseases like macular degeneration and glaucoma can be detected by the eye doctor well before they cause symptoms. Since those symptoms include irreversible vision loss, we should all be motivated to make that appointment!

Medicine is ever changing. Research avenues that seem promising turn into dead ends. Dead ends become detours to unexpected and exciting places. Maybe in the future, we will have drops or supplements or some other way to keep our eyes young. But for now, nothing can be said to be certain, except death, taxes. . . and presbyopia.

Richard P. Holm, MD passed away in March 2020 after a battle with pancreatic cancer. He is founder of The Prairie Doc®. For free and easy access to the entire Prairie Doc® ® library, visit www.prairiedoc.org and follow Prairie Doc® on Facebook. Dr. Debra Johnston is a Family Medicine Physician at Avera Medical Group Brookings in Brookings, SD.