Presbyopia: Why Near Vision Changes After 40 and What Helps

Sooner or later it happens to everyone. You find yourself holding your phone at arm's length, turning up the brightness to read a menu, or taking off your glasses to see small print. This is presbyopia, the gradual, age-related loss of the eye's ability to focus on close objects. It usually becomes noticeable in the early to mid-40s and continues to progress until around the age of 60 to 65.

Presbyopia is not a disease, and it is not caused by doing too much close work or by wearing glasses. It is a normal part of ageing that affects people regardless of whether they have had perfect vision all their lives. The good news is that there are more ways to manage it than ever before, from simple reading glasses to progressive lenses, multifocal contact lenses, eye drops and surgical options. This guide explains why presbyopia happens and helps you compare the choices.

Why presbyopia happens

To see clearly up close, the eye must increase its focusing power, a process called accommodation. A ring of muscle inside the eye, the ciliary muscle, contracts and relaxes the tension on fine fibres (zonules) attached to the lens. In a young eye, the elastic lens then becomes rounder and more powerful, bringing near objects into focus. Our guide to how vision works describes this process.

The lens keeps growing throughout life, adding new layers of fibres. Over the decades it becomes larger, denser and much less flexible. Although the ciliary muscle continues to work, the hardened lens can no longer change shape enough. As a result, the range of accommodation falls steadily with age:

Changes in the ciliary muscle and the geometry of the eye may also contribute, but the stiffening of the lens is considered the main cause. The same lens later in life may develop cloudiness, which is a cataract.

Symptoms

• Difficulty reading small print, labels, menus or phone screens
• Holding reading material at arm's length to see it clearly
• Needing brighter light to read
• Eye strain, tiredness or headaches after close work
• Blurring when switching focus from distance to near
• Difficulty with fine tasks such as threading a needle or reading a map in the car
• Short-sighted people taking off their glasses to read

Symptoms tend to be worse at the end of the day, when tired or in dim light, because the pupils are larger, which reduces depth of focus.

How presbyopia interacts with other refractive errors

• Hyperopia (long-sightedness): people with hyperopia often notice presbyopia earlier, sometimes in their late 30s, because they have used part of their focusing reserve all along.
• Myopia (short-sightedness): people with low to moderate myopia may find they can read well simply by taking off their distance glasses. However, they will usually need bifocals or progressives if they want one pair of glasses for everything.
• Astigmatism: uncorrected astigmatism can make presbyopic symptoms more noticeable.

Our overview of refractive errors explains how all these focusing problems differ.

Diagnosis

Presbyopia is diagnosed during a routine eye examination. The optometrist or ophthalmologist measures your distance prescription, then determines how much extra power you need for close tasks, known as the addition or ADD. The addition depends on your age, the distances at which you read and work, and your personal needs. It typically starts at around +0.75 to +1.00 dioptres in the early 40s and increases gradually to around +2.00 to +2.50 by the 60s.

Because many eye diseases, including glaucoma, diabetic retinopathy and macular degeneration, become more common after 40, an eye examination when presbyopia starts is a valuable opportunity to check the overall health of your eyes, not just your prescription. Our article on your eyes after 40 covers what else changes.

Spectacle options

Reading glasses

Reading glasses are single-vision lenses with plus power, designed for close work only. They are simple, affordable and effective, especially for people who have good distance vision without glasses. Ready-made readers from pharmacies can be a reasonable stopgap if both eyes need the same power and you have no significant astigmatism. However, they cannot correct differences between the eyes or astigmatism, and they do not replace an eye examination. The main drawback of readers is that distance vision is blurred through them, so they need to be put on and taken off. Our guide to reading glasses has tips on choosing them.

Bifocals

Bifocals have two distinct zones: the upper part for distance and a visible segment in the lower part for reading. They give wide, clear zones for both distances, but there is a visible line and no clear zone for intermediate distances such as a computer screen.

Progressive lenses

Progressive addition lenses (varifocals) provide a smooth transition from distance at the top, through intermediate in the middle, to near at the bottom, with no visible line. They allow clear vision at all distances with one pair of glasses. The trade-off is that the zones are narrower than in single-vision lenses, and there are areas of distortion at the sides. Most people adapt within one to two weeks, but some find it difficult. Correct fitting and frame height are essential. Our article on getting used to progressive lenses has practical advice.

Office and computer lenses

Occupational or office lenses are designed for intermediate and near distances, for example from the computer screen to a document on the desk. They offer wider zones than standard progressives at these distances and can be especially helpful for people who spend many hours at a desk, though they are not suitable for driving.

Contact lens options

Multifocal contact lenses

Multifocal soft and rigid contact lenses have zones of different power, usually in concentric rings or a gradual blend. Both eyes see near and far simultaneously, and the brain learns to select the clearer image. Many people find they can manage most daily tasks without glasses. Possible downsides are slightly reduced contrast and sharpness, haloes around lights at night, and the occasional need for reading glasses for very fine print or in dim light. Daily disposable multifocals are widely available. For more on lens types and hygiene, see our contact lenses guide.

Monovision

In monovision, one eye (usually the dominant eye) is corrected for distance and the other for near. The brain learns to use whichever eye gives the clearer image for each task. Monovision can be achieved with contact lenses or surgery. It works well for many people, but it reduces depth perception and can make night driving harder. A trial with contact lenses is strongly recommended before any permanent surgical monovision. A modified approach, sometimes called mini-monovision or blended vision, uses a smaller difference between the eyes to reduce these drawbacks.

Eye drops for presbyopia

In recent years, eye drops have been approved in some countries to temporarily improve near vision in presbyopia. The best-known contain a low concentration of pilocarpine, a drug long used for glaucoma. These drops make the pupil smaller, which increases depth of focus, much like the pinhole effect of a camera aperture. Other drops with a similar pupil-narrowing (miotic) action have also been developed.

• The effect lasts several hours and wears off, so drops must be used regularly.
• They work best for people with early to moderate presbyopia and are not a replacement for glasses in advanced presbyopia.
• Possible side effects include headache, brow ache, eye redness and dimmer vision in low light. Night driving may be harder.
• Rarely, miotic drops have been associated with retinal tears or detachment, so people with risk factors such as high myopia or previous retinal problems need careful assessment.
• They are prescription medicines, and availability varies by country. Your eye doctor decides whether they are appropriate for you.

Surgical options

Surgery can reduce dependence on reading glasses, but every option involves compromises, and results vary. A thorough consultation with an ophthalmologist is essential. See our guide to eye surgery options for a broader overview.

• Refractive lens exchange or cataract surgery with premium intraocular lenses: the natural lens is replaced with an artificial one. Multifocal, trifocal and extended depth of focus (EDOF) lenses can provide a range of vision from distance to near. Possible drawbacks include haloes and glare at night and somewhat reduced contrast. Because the natural lens is removed, a cataract cannot develop later. This option is more common from the 50s onwards.
• Laser monovision or blended vision: LASIK, PRK or SMILE are used to set one eye for distance and the other for near or intermediate vision. A contact lens trial beforehand is recommended.
• Presbyopia-correcting laser profiles: some laser treatments create a multifocal cornea; these are used in selected patients.
• Corneal inlays: small devices implanted in the cornea of one eye were introduced but have been largely withdrawn or used rarely because of complications and limited benefit.

Can exercises or supplements prevent presbyopia?

No. Presbyopia is caused by structural changes in the lens, and there is no good evidence that eye exercises, eye yoga, special diets or supplements prevent or reverse it. Exercises that move the eyes or focus at different distances may relieve strain and make the eyes feel more comfortable during long reading or screen sessions, but they do not restore the lens's flexibility. Delaying reading glasses does not make the eyes stronger either; it simply causes unnecessary strain.

Practical everyday tips can make life easier: use good, direct lighting for reading; increase font sizes on phones and computers; keep a pair of readers in key places; and use the 20-20-20 rule to rest the eyes during screen work.

When to see a doctor

Book an eye examination when you first notice difficulty with near vision, and then as recommended by your optometrist, often every one to two years. This allows your prescription to be updated and, importantly, your eyes to be checked for conditions such as glaucoma, macular degeneration, diabetic retinopathy and cataract, which become more common with age and may not cause symptoms early on.