"Stop that before you go blind," my mother would warn, having once again busted me, awake after bedtime. At age 10, my sins typically involved reading a Judy Blume novel by flashlight, under the covers to avoid detection.
I'd consider my mother's threat briefly, then return to my vice as soon as she left. "Tiger Eyes" always trumped tired eyes -- until, decades later, I needed glasses.
Now a large study published recently in the Archives of Ophthalmology shows that nearsightedness, or trouble seeing objects at a distance, rose by 66 percent over a 30-year period -- an increase that seems to dovetail with our growing engagement in "near work," like reading and using computers, smartphones, e-book readers, and other electronic devices. I have to wonder: Was Mom right all along?
Nearsightedness on the Rise
She may indeed have been onto something. Nearsightedness is one of several types of refractive errors, which are changes in the shape of the eye that commonly cause blurry vision. While the recent study didn't look at the reasons nearsightedness is on the rise, near work may be partly responsible.
"Although nearsightedness, or myopia, is not completely understood, it may be related to changes in the focusing process as the gaze moves between near and distant objects," explains lead researcher Susan Vitale, Ph.D.
Imperfect focus leads to blurred images, she says, which trigger the release of chemicals that may lengthen the eyeball. Recent studies suggest that the result of doing more near work -- spending less time outdoors focusing on objects in the distance -- may contribute to the problem.
What is clear: The risk factors for myopia are complex, and researchers are working to understand the causes, develop treatments, and identify the biological evolution of the condition. While worsening eyesight is frustrating, it's usually correctable. By midlife, most of us have already compensated for refractive errors with glasses, contact lenses, or LASIK surgery.
And even though we can't prevent refractive errors, we can help protect against the more serious sight-stealing conditions that become more common as we age, such as macular degeneration (loss of central vision), glaucoma (damage to the optic nerve), and cataracts (clouding of the lens), as well as uncomfortable problems like dry, tired, or itchy eyes.
Stay on top of your eye health and you should be able to see clearly for years. In fact, says Rachel Bishop, M.D., an ophthalmologist at the National Eye Institute in Bethesda, Maryland, "there's plenty you can do to retain good vision throughout your life."
"The same healthy diet that's good for your heart, brain, and the rest of your body is also good for your eyes," Bishop explains. Several studies have shown that people who eat foods rich in vitamins C and E, lutein, and zeaxanthin, all antioxidants, are less likely to develop macular degeneration (MD) and cataracts.
In particular, dark leafy greens, corn, tomatoes, and broccoli are great sources of these compounds. "In general, if it comes from the garden and is brightly colored, it's good for eye health," says Paul Dickinson, M.D., an assistant professor of ophthalmology at Wake Forest University in Winston-Salem, North Carolina.
(While Mom's advice to eat carrots for good vision isn't completely off base, the beta-carotene they contain hasn't been found to be as protective as these other antioxidants.)
Get eight servings of produce a day, and ask your doctor if you need to supplement with any daily vitamins. Although higher amounts of supplemental antioxidants have been found to slow the progression of MD in people who already have the disease, there's no need for the rest of us to take special antioxidant eye supplements.
Research also suggests that the heart-healthy omega-3 fatty acids found in fish like salmon, sardines, and mackerel may help protect against MD too. Eating two or more servings a week is associated with the lowest risk.
And there's sound evidence that cutting back on sugar may benefit vision, as well as blood sugar and weight. Studies show that people who eat fewer simple sugars and refined carbohydrates and more complex carbs have a reduced risk of developing MD. Simple switches like eating whole-grain instead of white bread can help cut your sugar intake and may protect vision.
Your risk for developing MD, cataracts, and glaucoma may increase with age and conditions like high blood pressure or cholesterol, diabetes, and obesity. Preventing these problems can also help keep your eyes healthy.
First, don't smoke. Not only does smoking harm the heart and lungs, but recent research also shows that people who smoke have triple the risk of MD and are also more likely to develop cataracts, possibly because of nicotine's effects on blood vessels in the eye.
And while there's no good evidence that so-called eye exercises can help benefit most vision problems, good old-fashioned, whole-body exercise does show promise. The same aerobic activities that strengthen your cardiovascular system (such as walking and running) have been shown to help protect against MD, in part because they help deliver oxygen to the eyes. Aim to move for at least an hour a day on most days.
Symptoms like blurry vision and headaches can alert you that it's time for a new eye prescription. But diseases like MD and glaucoma often aren't noticeable until they've already damaged vision. That's why it's crucial to have your eyes checked at age 40 and regularly thereafter based on your doctor's advice, especially if you have a family history of either condition.
A complete eye exam includes a variety of tests to assess the ability of your eyes to focus, detect signs of infection, and check for glaucoma. Ask your eye doctor for a comprehensive glaucoma evaluation too, including an eye pressure check and a dilated eye exam.
Contact lens safety is critical for good vision. "When patients come to me with eye infections or ulcers, 9 times out of 10 they're contact users," Dickinson says.
Contacts can slightly alter the surface of the eye and increase the risk for infection, which can lead to vision loss. Clean your contacts, wash your hands thoroughly before touching them, and never sleep in them.
You can also prevent infections by avoiding eye rubbing, not sharing eye makeup, and not using contaminated applicators. See your doctor immediately if you develop symptoms like redness, pain, watery eyes, or blurry vision.
Sun damage is cumulative, and sunlight can harm your eyes and raise the risk of MD and cataracts all year round.
"Shop for sunglasses the way you would sunscreen," Bishop says. "Look for glasses that block both UVA and UVB rays." Wear goggles or safety glasses when playing contact sports, working in the yard, or doing home repairs; protective eyewear can prevent 90 percent of eye injuries.
- Treatments for Tired, Itchy, or Dry Eyes
- Look-Younger Tricks for Tired Eyes
- Caring for Aging Eyes: The Latest in Contact Lenses