If eyesight fades over time because of aging or an eye disease, the Mayo Clinic Health Letter suggests:

-- Reducing differences in brightness. Equalize indoor and outdoor light sources by leaving some house lights on during bright sunny days.

-- Reducing glare by covering shiny surfaces, such as a polished table, with a cloth. Dark-colored place mats can help at mealtime. Use furnishings with a flat or matte finish.

-- Lighting up dark spots. Install lighting in dark areas, such as inside closets. Keep a pocket flashlight handy for dark areas.

-- Using bright, direct lighting. Position an adjustable lamp about 4 to 8 inches from reading material or a close-up task. Keep the lamp slightly to one side to reduce glare. If possible, position the light over the shoulder on the side of the better-seeing eye.

-- Taking advantage of natural light by positioning windows to the side or behind tasks.

-- Using a dark background when reading to reduce glare. A piece of dark construction paper can cover areas of text not being read.