One minute we’re reading the small print on the back of the cereal packet, the next, even the generously sized font on a Kindle is a struggle. At least that’s how it can feel when we reach mid-life and the eyesight we’ve long taken for granted starts to fail.
With age, the eye’s lens becomes less flexible, meaning it can’t change shape as easily to bend light rays passing through the pupil towards the retina at the back of the eye. As a result, it becomes more difficult to focus on objects up close – part of the natural ageing process known as presbyopia so prevalent that, by our mid-40s, most of us wear reading glasses.
“Presbyopia is inevitable for most of us – there aren’t any lifestyle changes we can make to avoid it – although it’s less common in people who are short-sighted as their eyes are used to focusing up close,” says Professor Andrew Lotery, an ophthalmologist at Southampton University.
“Your vision won’t worsen if your presbyopia isn’t picked up immediately, but without reading glasses it will obviously be harder to see up close.”
In one respect, presbyopia can be genetic, like many sight conditions, but, says ophthalmologist Dr Jorn Jørgensen, founder of the EuroEyes Laser Eye Clinic London, increased time spent staring at screens is straining our eyes to the extent that what was once a problem almost exclusively for the over 40s is developing at an ever younger age: “When you are working at short focus, the lens needs to bend the whole day, which means the lens gets stiffer more quickly, and people who spend a lot of time on the computer may get presbyopia earlier. We are seeing more pre-presbyopia in people aged 38 or 39 now,” he says.
With increasingly sophisticated laser surgery available, however, reading glasses need not be the only solution. “The procedure costs about £5000 [NZ$10,621] and is our main surgery. We do 60,000 patients a year,” says Jørgensen.
There are other conditions that also play a part in age-related vision issues, and while not all have cures, there is plenty we can do to optimise our eyesight. Here’s what we’re most at risk of developing – and how to reduce our chances of being affected.
Cataracts
A third of people aged 65 or over have cataracts, caused by a build-up of proteins in the lens at the front of the eye, making vision hazy and eyes sensitive to light.
“As you get older your crystalline lens, as it’s called, becomes more cloudy,” says Lotery. Although 8-25 per cent of cataract cases are genetic, there are steps we can all take to reduce our chances of getting them.
“There’s definitely evidence that UV radiation is a risk factor for cataracts,” says Professor Daniel Ezra, oculoplastic consultant at London’s Moorfields eye hospital. “Good sunglasses should screen out those UV wavelengths that are responsible.”
Reducing your salt intake is also advisable, according to a 2000 study published by the American Journal of Epidemiology.
As is ensuring you are getting enough zinc, a mineral found in red meat, poultry and nuts. Zinc helps bring Vitamin A from the liver to the retina in order to produce melanin, a protective pigment in the eyes.
Vitamin E protects the retina, the light-sensitive layer of tissue at the back of the eyeball. One analysis found consuming over 7mg of vitamin E daily could reduce the risk of cataracts by 6 per cent (the NHS recommended daily allowance is 4mg for men and 3mg for women).
“I recommend seeds and nuts, which have lots of vitamin E,” says Dr Hawkes, a consultant ophthalmic and oculoplastic surgeon at the Cadogan Clinic in Chelsea, while Jørgensen believes the most important nutrients for our eyes are Omega-3 fatty acids, found in oily fish such as salmon: “We believe they protect against cataracts.”
According to an analysis of six studies of more than 170,000 patients published in 2020 in the International Journal of Ophthalmology Press, exercise can help increase antioxidant enzymes in the eye. It found increased physical activity was associated with a 10 per cent reduced risk of cataracts.
However, the biggest lifestyle problem causing cataracts in our society is smoking. “Smoking causes oxidative stress in the body which increases the ageing of the eye,” Lotery says.
Although cataracts can form from 50, most sufferers don’t require surgery to replace the faulty lens with a synthetic version until their late 60s. Cataract surgery is one of the most common operations on the NHS, with almost half a million procedures performed a year. “It’s mostly done using anaesthetic eye drops, with surgery taking under 20 minutes,” says Lotery. “There is a small risk of infection – about one in 1000 – but you can be reading very well as soon as the day after surgery.”
Glaucoma
This condition is caused by fluid building up in the front of the eye, which increases pressure in the eye – intraocular pressure (IOP) – and gradually damages the optic nerve that transfers visual information from the eyes to the brain. “Glaucoma affects about two per cent of people over 40,” says Lotery, although symptoms – rainbow-coloured circles around bright lights, loss of vision and blindness – peak in people in their 70s and 80s.
“Sometimes it’s called the ‘thief of sight’ because you may not be aware you have it for a long time. It affects your peripheral vision first, which is why it’s not always obvious,” Lotery says. “There are some early-onset genetic forms and it can develop in your 20s and 30s. So if you have a family history of it you should have your eyes tested regularly.”
Aerobic exercise can help reduce symptoms. A 2021 study published in the Indian Journal of Ophthalmology found 30 minutes on a treadmill reduced participants’ IOP, and research has found those with active lifestyles are less likely to develop glaucoma in the first place.
Quitting cigarettes can also lower your chances of developing glaucoma because smoking limits blood supply to the optic nerve.
“If you smoke, give up,” Hawkes says. “Not smoking will benefit your blood vessels and ease inflammation.” Lotery, on the other hand, warns that steroid creams available on prescription can be a risk factor for increasing eye pressure if applied near the eyelids.
The NHS advises everyone to have an eye test every two years, which, given the silent progress of glaucoma, is particularly important in spotting the condition. “While it’s not possible to reverse damage already done to eyesight, if it’s detected early eye drops applied once a day to change the eye pressure to normal range can prevent it worsening,” Lotery says.
Ezra adds: “There are laser procedures that help the drainage mechanism in the angle of the eye between the iris and the cornea. One of the most common operations is day surgery to insert microscopic stents that form a communication between the inside and outside of the eye so if pressure gets too high it will work its way out through the stent.”
Age-related macular degeneration
The most common cause of vision loss in the elderly in the developed world is age-related macular degeneration (AMD). This happens when the macula, the part of the retina responsible for our central vision, is damaged, either when retinal cells die (which is called dry AMD and is more common) or when unhealthy blood vessels grow into the macula (known as wet AMD).
“By age 75, one in three people will have it; by 85 one in two,” Lotery says. “As the elderly population increases, we’re seeing a year-on-year increase of 10 per cent of people needing help.”
Progression varies, but sufferers, usually aged over 50, often find the first symptom is blurred vision. Dark spots can sometimes appear and colours seem faded. “AMD can cause hallucinations but, because it affects central vision, sufferers should always maintain some peripheral sight,” Lotery says.
Although up to 70 per cent of cases have a genetic factor, even if your genes do make you susceptible, there are measures you can take to lower your risk of developing AMD. “Research has shown that following a Mediterranean diet, with lots of green vegetables, salads, chicken and fish, can slow progression by reducing inflammation in the body,” Lotery says.
Zinc, which maintains the health of cells and decreases with age, and is found in meat, shellfish and dairy foods, has been found to slow the development of macular degeneration.
Research published in the Journal of the American Medical Association found people with the highest intake of carotenoids called lutein and zeaxanthin (present in spinach, kale and egg yolks), which have antioxidant qualities that protect the retina, had a 43 per cent lower risk of macular degeneration than those with the lowest intake.
“You can buy lutein and zeaxanthin supplements in the chemist,” says Lotery, who advises stopping smoking and cutting down on alcohol to reduce inflammation: moderate and heavy drinking were shown to increase the risk of developing AMD in a recent study in the journal Eye Care.
Keeping fit, again, is important, with 2006 research in the journal Ophthalmology finding exercise three times a week lowers your risk by reducing blood pressure.
AMD is incurable, but treatment is available for wet AMD with injections of anti-VGEF (vascular endothelial growth factor) drugs into the eyeball, which will inhibit the growth of abnormal blood vessels. “The injections have to be given regularly, sometimes monthly, but can help maintain vision to driving level standards,” Lotery says. “Some of my patients have been having injections for 10 years.”
There is, at present, no treatment for dry AMD in the UK, although, he says, “a treatment has just gone on the market in the US which is an injection that inhibits inflammation, by targeting a protein called complement, which sufferers make too much of, and will hopefully be approved in the UK soon”.
Diabetic retinopathy
Affecting around one-third of diabetes sufferers, and more prevalent in the over 50s, diabetic retinopathy develops gradually as high blood sugar levels damage blood vessels in the retina. This is the part of the eye that converts light into signals sent to the brain, which turns them into images. “It’s becoming much more common because of increasing rates of obesity, which can lead to type 2 diabetes (which accounts for up to 95 per cent of all cases),” Lotery says.
Symptoms include pain, shapes floating in your field of vision and, if it’s not picked up early, loss of vision. “The problem is that by the time you get symptoms, you’re 20 to 30 years down the line and it’s too late,” says Ezra. “All of the important groundwork for minimising risk will happen in those asymptomatic years. If you’re diabetic, you have to control your blood-sugar levels from the outset, which is not easy, and it’s essential not to smoke.
“Smoking also damages and narrows the blood vessels, preventing enough blood getting to the peripheral tissues, which is essentially what causes diabetic retinopathy, so together they increase the risk exponentially.”
Lotery adds: “Risk factors for diabetic eye disease progressing include high blood pressure, high cholesterol and high blood sugar. So keeping all of these under control is very important. Aerobic exercise such as running, cycling and walking to keep as fit as possible will help.”
Indeed, last year research in the journal Cureus found that the “protective and anti-inflammatory effects on the retina” physical exercise prompted were linked to the delayed onset of diabetic retinopathy.
If you have diabetes, NHS advice is to get your eyes tested at least once a year, where an optometrist may take pictures at the back of your eyes to check for any changes to retinal blood vessels or perform a dilated eye exam using eye drops to stop your pupils becoming smaller when lights are shone into your eyes to examine the optic nerve and retina. “Leaky blood vessels and new blood vessel growth are also seen in diabetes and these respond very well to eye injections, although laser treatment can also effectively address these problems,” Ezra says.
Dry eye
Dry eye affects as many as 30 per cent of older people, the majority of whom are women.
The condition occurs when the eyes don’t produce enough tear fluid. Tear fluid is made up of water, oil produced in the eyelids’ meibomian glands (the ones along the edge of the eyelids) and mucous. “Blinking has a windscreen wiper effect to spread fluid over the eye and keep it moist,” Ezra says. “A decreased frequency of blinking with age in combination with decreased quality of the tear film as you get older causes the sensation of dry eye.”
Some studies suggest that the condition is more prevalent in postmenopausal women because of declining oestrogen levels, which affect oil production. “A link has been demonstrated, but it’s not conclusive,” says Ezra. “Staring at a screen definitely makes dry eye worse, because people blink dramatically less frequently. We’re not biologically designed to do one task for hours on end. It’s almost an epidemic in offices now. We advise people to take regular screen breaks.”
For this, Hawkes recommends the 20-20-20 rule: ie, that every 20 minutes you look out of the window at something 20 yards away for 20 seconds.
A deficiency in beta-carotene (an antioxidant carotenoid found in foods such as carrots and kale), which maintains light-sensing cells also known as photoreceptors located at the back of the retina, has been linked to dry eye, and Jørgensen believes Omega-3 fatty acids are helpful: “Ninety per cent of dry eye is caused by meibomian gland dysfunction. Omega acids are known to stimulate the glands to produce more oil.”
In some types of dry eye, the meibomian glands get inflamed and the oils they produce become solidified. “A warm compress – a flannel, for example – placed over the eye will help melt the oils and improve tear quality,” Ezra says.
Alcohol, meanwhile, is a “significant risk factor”, according to a meta-analysis of studies published in the International Journal of Ophthalmology in 2016 and is, in general, detrimental to eyesight, says Hawkes: “Reducing your alcohol intake can help to improve blood flow, oxygen and nutrients to your organs, including the eyes.”
Fortunately, treatment is available. “Over-the-counter drops contain a tear substitute called hypromellose,” says Lotery, while in more severe cases, surgery can stop your tears draining away from your eyes. “Plugs are inserted into the lacrimal puncta – the openings in the eyelids where tears drain into the side of the nose. It’s a minor operation available on the NHS.”
