On a visit to my ophthalmologist for what I thought would be a routine eye examination, he took the pressure in my eyes, sat back and said, “The pressure is 22 in both your eyes. Last year at this time it was 11. We’ll have to watch this. You may be developing glaucoma.” I had just become what the medical profession calls a “glaucoma suspect.” Glaucoma refers to a group of diseases that can produce blindness. It damages the optic nerve, leading to progressive, irreversible vision loss. Glaucoma affects one in 200 persons aged 50 and older, and one in ten over the age of 80. People with glaucoma may or may not have an elevated intraocular pressure (IOP), that is, too much pressure inside their eyeballs, which is what my doctor had just discovered in me. Glaucoma usually, but not always, begins with increased IOP. Many things can...