Living with diabetes means you’re at risk of developing problems with your eyes. The most common vision problem for those with diabetes is a condition called diabetic retinopathy. If you don’t treat this in time, you could end up losing part or all of your vision. Thankfully, however, controlling your diabetes can help prevent diabetic retinopathy and other eye problems developing.
According to the most up-to-date figures from the health charity Diabetes UK, more than 1,700 people in the UK have their sight seriously affected by diabetes every year (i). Indeed, diabetes is responsible for five per cent of all sight loss in the country, with seven per cent of people newly registering as blind in England and Wales having lost their sight because of diabetes (i).
Perhaps even more alarming is the fact that almost half of people with type 1 diabetes and a quarter of those with type 2 diabetes have some degree of diabetic retinopathy. This increases to almost everyone with type 1 diabetes and two thirds of those with type 2 diabetes after living with the disease for 20 years.
What is diabetic retinopathy?
If you have diabetic retinopathy it means your diabetes is affecting your retina, the light-sensitive layer of cells at the back of your eye. Your retina is important because it converts light into electrical signals. These signals are sent to your brain, which in turn converts them into the images you see. So if your retina isn’t working properly, you won’t be able to see very well.
Your retina needs a constant supply of blood, which it gets via the blood vessels in your eyes. But over time, having a high level of sugar in your blood can damage and weaken these blood vessels, causing a range of problems such as blockages, bulging, bleeding and leaking fluids. In time new abnormal blood vessels can grow that are very weak and particularly prone to bleeding. All of these problems can damage the cells of your retina. And if any damaged blood vessels bleed into the centre of your eye it can also affect your vision by blocking the light going into the retina.
Different parts of the retina can be damaged by diabetic retinopathy, including the macula – the small central part of the retina that’s responsible for your central vision and your ability to see fine details. Called diabetic maculopathy, this is when the blood vessels in your macula become blocked, causing a build-up of leaked fluids. When this happens it can affect your central vision, and eventually you may not be able to read or drive. Meanwhile the outer part of the retina, which is used for peripheral vision, can also become damaged.
What are the symptoms of diabetic retinopathy?
Many people with diabetic retinopathy don’t notice any symptoms during the early stages of the condition. If it goes undiagnosed and progresses, however, it can lead to partial or total loss of vision. Some people, on the other hand, may notice one or more of the following:
Blurred or patchy vision
Seeing floaters (spots or dark strings in your vision)
Seeing flashes of ligh
Sudden vision loss or dark areas in your vision
Difficulty seeing in the dark
Frequently changing vision (this can change from one day to the next
Poor recognition of colours
Eye pain or redness
However the fact that there aren’t always any noticeable symptoms during the early stages – when treatment is much more simple and effective than during the later stages – means it’s really important to go for regular eye checks.
Everyone living with any type of diabetes who is aged 12 years or older is invited to regular eye screening at least once a year. This includes testing your vision and also taking digital photographs of your retinas to check for potential problems that might be developing. You may be given eye drops to make your pupils as wide as possible just before the photographs are taken – this doesn’t hurt but your eyesight may be quite blurry for a few hours afterwards, so it’s a good idea to take someone to your appointment who can make sure you get home safely.
The results of your eye screening should be sent to you within six weeks.
What are the stages of diabetic retinopathy?
The results of your eye screening will tell you whether or not you have any potential problems with your eyes. If there aren’t any problems, you’ll be asked back again for another screening in a year or so. If a problem has been detected, you may be asked back for another eye check-up sooner or for more frequent eye check-ups, or you may be referred to an eye specialist. All of these factors depend on the stage of diabetic retinopathy that’s been detected:
Stage 1: background diabetic retinopathy
If your test reveals you’re at the first stage of diabetic retinopathy it means the blood vessels in your retina have developed tiny bulges called microaneurysms that leak small amounts of blood (this may appear on your test results letter as R1).
You don’t need any treatment at this stage, and your sight shouldn’t be affected. However you’ll be identified as having a higher risk of developing problems with your eyesight in the future (if both of your eyes are affected your risk will be even greater). While you don’t need any treatment, you’ll usually be advised about ways to prevent the problem from progressing (see Ways to help yourself, below), such as keeping an eye on your blood sugar levels as well as your blood pressure and cholesterol, and making healthy lifestyle choices.
Stage 2: non-proliferative (or pre-proliferative) diabetic retinopathy
If your test results mention R2, you’re at the second stage of diabetic retinopathy. This means your eye screening has picked up more severe and widespread changes in your retina, including more bleeding.
Again you won’t need any treatment, but there’s a high risk that your vision will be affected in time, so you’ll usually be offered more regular eye screening appointments to keep a better eye on how these changes in your retina are progressing.
Stage 3: proliferative diabetic retinopathy
The third stage – R3 – carries the highest risk of sight loss. If your results show you’ve reached this stage it means your retina has been affected by new blood vessels and scar tissue, which can cause more significant bleeding. It can also put you at risk of retinal detachment, where your retina pulls away from the back of your eye.
At stage three you’ll be referred to a specialist so that you can have treatment to keep your vision as stable as possible (read on for details), though if you have already lost some vision it may not be possible to restore it. If you don’t have any treatment, however, you have a 50 per cent chance of losing your sight within two years and a 90 per cent chance of losing any useful vision after 10 years (ii).
Your test results may also indicate whether or not any diabetic maculopathy – where the macula in the centre of the retina is affected – has been detected (this is usually referred to as M0 if no problem has been found or M1 if fluid is starting to build up in your eye).
No treatment is usually needed if you’re in the early stages of diabetic maculopathy. But if the condition has progressed you may need to see a specialist about having treatment to stop it getting any worse.
Are you at risk of developing diabetic retinopathy?
Diabetic retinopathy is more common in people with type 1 diabetes. However there are several other things that may increase your risk whatever type of diabetes you have, including:
How long you’ve had diabetes (the longer you’ve had it, the higher your risk of developing diabetic retinopathy)
How well you control your blood sugar (studies suggest people with poor blood sugar control are more likely to develop complications including diabetic retinopathy – though some experts have found even some people with well-controlled blood sugar develop diabetic retinopathy at some stage (iii))
Having high blood pressure
Having kidney disease
Being pregnant (though having gestational diabetes – where diabetes develops during pregnancy then relapses – isn’t usually thought to cause eye problems)
Having high cholesterol
Living with obesity
Coming from an Asian or Afro-Caribbean background
Diabetic retinopathy: treatment and prevention
If you’ve been diagnosed with proliferative retinopathy or diabetic maculopathy, you may be offered the following treatments:
Laser treatment This aims to treat the growth of new blood vessels in the retina in cases of proliferative diabetic retinopathy and also in some cases of diabetic maculopathy. The laser aims to seal any leaking blood vessels and stop new blood vessels growing any further. But while this treatment can help stop your vision getting any worse, it doesn’t usually improve existing vision problems. The procedure is usually carried out in hospital but you’ll probably be treated as an outpatient, which means you won’t have to stay in hospital overnight.
Eye injections These are often used to treat severe diabetic maculopathy. Again the procedure is offered on an outpatients’ basis, and unlike laser treatment they don’t just help stop your vision getting any worse but can also make your existing vision better.
You’ll usually be given injections once a month to start with, then you’ll have them less frequently – or stop having them altogether – once your vision start to stabilise.
Injected medicines are called anti-VEGF medicines, but if these aren’t effective you may be offered injections of steroid medicines.
Eye surgery If your diabetic retinopathy is very advanced or you have advanced diabetic maculopathy, you may be advised to have vitroretinal surgery to remove some of the jelly-like substance called vitreous humour from your eye. This is usually offered to people who have extensive scar tissue that’s likely to cause, or has caused, retinal detachment, or when there’s a large amount of blood in the eye.
Vitroretinal surgery is usually carried out under local anaesthetic and sedation, and you should normally be able to go home the same day, or sometimes the day afterwards.
Ways to help yourself
Whether you have any signs of diabetic eye problems or not, there are things you can do that may help prevent them developing, or to stop them getting worse if they’ve already started to develop:
Keep your blood sugar under control: according to the NHS, controlling your diabetes can help prevent vision problems developing even if you’re already in the early stages of diabetic retinopathy (iv). This means eating healthily (include plenty of green leafy veg and other colourful fruits and veg in your diet as these may help keep your macula healthy), staying active, taking any medication you’ve been prescribed for your diabetes as your doctor has instructed and going for check-ups whenever you’re invited. There’s more about managing your diabetes in our guide to diabetes causes and treatments.
Avoid smoking, since there’s evidence smoking may make retinopathy worse (iii) (if you’re a smoker, find out about stop smoking aids that can help you cope with nicotine cravings in our guide to stop smoking)
Try not to exceed the recommended limit for drinking alcohol, which is 14 units of alcohol a week for adult men and women (find more tips on cutting down by reading our guide to alcohol misuse)
Always keep your appointments for eye screening
Look out for any changes in your vision, such as floaters, your vision getting dimmer and difficulty seeing in the dark
Other diabetes-related eye problems
Diabetic retinopathy isn’t the only eye problem that can be caused by having diabetes. Other conditions include:
Cataracts (people with diabetes have double the risk of developing cataracts (i), which is when the lenses in your eyes become cloudy – find out more by reading our guide to cataract signs, symptoms and treatment)
Glaucoma (if you have diabetes your risk of developing glaucoma is one and a half times that of someone who doesn’t have diabetes (i): glaucoma is when your optic nerve becomes damaged – our guide to living with glaucoma has lots more details)
Meanwhile, other eye conditions that are more common in people with diabetes include dry eyes, corneal abrasions and uveitis (inflammation of the middle layer of the eye). If you have diabetes you may also lose your ability to focus on nearby objects prematurely (called presbyopia, this usually only affects people aged 40 and older), as the lens in your eye may become less pliable sooner than usual.
Natural support for blood sugar management
Keeping your blood sugar levels well managed is one of the most important things you can do to maintain good vision if you’re living with diabetes. But as well as eating a nutritious diet and exercising regularly, taking certain supplements may be helpful, as some are believed to help with blood sugar control.
However if you have diabetes always check with your GP before taking these or any other supplements, as there’s a risk your blood sugar could dip too low and put you at risk of a serious complication called hypoglycaemia (hypo).
Find out more about hypos in our guide to diabetes.
Please also note that no supplement should ever be used as an alternative to conventional diabetes medicines or medical care.
It may be a good idea to start with a good-quality multivitamin and mineral product. This can help make sure you have all the nutrients your body needs for your general health, particularly if you don’t always eat as healthily as you should.
Find out more about multivitamin supplements, including the variety of products on offer and which one may be suitable for you, by reading our guide to multivitamins and daily requirements.
Other supplements that may be helpful include the following:
A natural remedy used for centuries in traditional Chinese medicine, cinnamon is a spice that’s also often recommended by natural therapists for people with type 2 diabetes, as there is some evidence it may help support blood sugar levels (v).
Alpha lipoic acid
Some studies suggest this fatty acid and powerful antioxidant may help support blood sugar levels (vi) as well as improve insulin sensitivity in people with type 2 diabetes (vii). However, if you have diabetes always consult your GP before taking alpha lipoic acid as it may support insulin activity.
There is some evidence that people who have diabetes also have low magnesium levels (viii), possibly because diabetes or the medicines used to treat it may cause magnesium deficiency. Researchers have also discovered magnesium may even help with blood sugar control (ix).
Curcumin – a compound found in the curry spice turmeric – is believed to have several potential health benefits, including the ability to support healthy blood sugar levels (though to date most studies have been carried out in animals rather than humans, meaning the available evidence isn’t as convincing as it could be). Some researchers, however, have found that curcumin may help support healthy blood sugar level control in a study that looked at its effects in people with diabetic foot ulcers (x).
High-strength fish oils
Omega-3 fatty acids – particularly EPA and DHA, two omega-3s found in oily fish such as salmon, trout, sardines and mackerel, as well as fish oil supplements – are widely considered helpful for general health and wellbeing. Studies also suggest having low levels of omega-3s may be linked with diabetic retinopathy (xi). Fish oil supplements are widely available, but vegetarians and vegans can get these beneficial omega-3 fats too by taking supplements that contain omega-3 oils derived from marine algae.
Fenugreek seeds have a long tradition of use in some parts of the world, including in Ayurvedic medicine. These days, herbal practitioners recommend fenugreek seeds to people with diabetes, as they may help the body to produce insulin. There’s also some evidence fenugreek seeds may be helpful in controlling type 2 diabetes and reducing insulin resistance, though supporting studies to date are small in scale (xii). However, don’t take fenugreek if you’re pregnant or breastfeeding.
Best known for helping the body to absorb calcium, vitamin D is also thought to play an important part in regulating the immune system. Studies have also suggested that people with proliferative diabetic retinopathy may have lower vitamin D levels than people who don’t have diabetes (xiii).
Vitamin D deficiency is believed to be common in some countries including the UK, which explains why Public Health England advises adults and children over the age of one year old to consider taking a daily supplement containing 10mcg of vitamin D, particularly during autumn and winter (xiv). However if your skin is rarely exposed to the sun – if you spend most of your time indoors, for instance, or if your skin is always covered when you’re out and about – you may need to take vitamin D throughout the year. People with dark skin from African, Afro-Caribbean and South Asian backgrounds should consider taking vitamin D all year round too, PHE advises.
The recommended form of vitamin D is vitamin D3 or cholecalciferol, as it’s the natural form of vitamin D that the body makes when it’s exposed to sunlight. Vitamin D3 supplements are available in tablet form, and now you can get them in veggie-friendly drops too. However most vitamin D3 supplements are made from the fat of lamb’s wool, which means they’re unsuitable for vegans. The good news is that vegan vitamin D3 supplements sourced from lichen are now more widely available.
Found in dark-skinned fruits such as blueberries, cranberries, raspberries, blackberries and red grapes – as well as vegetables such as red cabbage, red onions and aubergines – anthocyanidins and their derivatives anthocyanins are potent antioxidant compounds. These substances are thought to help strengthen and repair the walls of blood vessels by protecting collagen in the body (collagen being the structural protein that gives blood vessels their strength).
Anthocyanidins are also available in supplement form (choose a product that combines anthocyanidins with vitamin C, as vitamin C supports the body’s ability to produce collagen).
If you’re living with type 1 or type 2 diabetes, your risk of developing problems with your eyes is higher than that of the general population. But there are things you can do to reduce that risk, including making healthy lifestyle choices that can help you manage your condition more effectively. To discover a wide range of general health conditions, take a tour around our pharmacy health library.
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(ii) Available online: https://patient.info/doctor/diabetic-retinopathy-and-diabetic-eye-problems
(iii) Available online: https://patient.info/diabetes/diabetes-mellitus-leaflet/diabetic-retinopathy
(iv) Available online: https://www.nhs.uk/conditions/diabetic-retinopathy/treatment/
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(x) Mokhtari M., Razzaghi R, Momen-Heravi M. The effects of curcumin intake on wound healing and metabolic status in patients with diabetic foot ulcer: A randomized, double-blind, placebo-controlled trial. Phytother Research: PTR (2020) 35(4):2099–107. Available online: https://onlinelibrary.wiley.com/doi/10.1002/ptr.6957
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(xiv) Available online: https://www.gov.uk/government/news/phe-publishes-new-advice-on-vitamin-d
Disclaimer: The information presented by Nature's Best is for informational purposes only. It is based on scientific studies (human, animal, or in vitro), clinical experience, or traditional usage as cited in each article. The results reported may not necessarily occur in all individuals. Self-treatment is not recommended for life-threatening conditions that require medical treatment under a doctor's care. For many of the conditions discussed, treatment with prescription or over the counter medication is also available. Consult your doctor, practitioner, and/or pharmacist for any health problem and before using any supplements or before making any changes in prescribed medications.
Christine Morgan has been a freelance health and wellbeing journalist for almost 20 years, having written for numerous publications including the Daily Mirror, S Magazine, Top Sante, Healthy, Woman & Home, Zest, Allergy, Healthy Times and Pregnancy & Birth; she has also edited several titles such as Women’ Health, Shine’s Real Health & Beauty and All About Health.