Diabetes describes a chronic condition whereby blood sugar levels rise to dangerous levels if steps are not taken to curtail them. Worryingly, untreated diabetes can lay the groundwork for a whole host of health problems, ranging from heart disease to nerve damage, making symptom awareness front and centre. When you leave your blood sugar levels to roam freely for a long time, you can put your eyes at risk too, according to Dr Chien Wong, director and consultant ophthalmic surgeon at OCL Vision . While eye problems caused by diabetes are ‘remarkably common’, they are unlikely to be one of the first symptoms you will experience. Dr Wong said: ‘In the UK, nearly all people with type 1, and almost two-thirds of those with type 2 diabetes, will suffer some degree of diabetic eye disease within 20 years of being diagnosed.’ The sudden sign in your vision that could signal diabetes – doctor. (Image: GETTY) Usually, the first sign to ring alarm bells is blurred vision , which can come ‘gradually or suddenly’, according to the doctor. High blood glucose levels can alter your ability to see by causing the lens inside your eye to swell, which can result in temporary blurring of eyesight. On the other hand, very low blood sugar levels can also spur on this symptom. However, your vision should return to normal once your blood glucose levels are back in the normal range, Diabetes.co.uk explains. Usually, the first sign to ring alarm bells is blurred vision, which can come gradually or suddenly. (Image: GETTY) ‘If your blood sugar levels are fluctuating over time, you may notice that your vision improves and worsens for periods of time,’ the health portal adds. Dr Wong added it’s ‘important’ for changes in the eyes caused by diabetes to be treated ‘early’. The doctor said: ‘Diabetes causes normal blood vessels in the retina – the sensitive nerve layer at the back of the eye – to become damaged over time. ‘When the blood vessels are damaged, they can leak fluid and cause swelling of the retina. Diabetes symptoms include increased need to urinate. (Image: Express.co.uk) ‘They could also stop working completely in areas, which can lead to growth of abnormal new blood vessels that bleed, and in advanced cases retinal detachment or glaucoma. ‘The key to preventing this from happening is identifying it early, before irreversible damage to vision occurs.’ One warning sign which could signal bleeding inside of your eye is sudden onset of floaters , which refer to small dots or squiggles in your vision. This symptom should be investigated ‘as soon as possible’ by an experienced optical professional, according to the doctor. Unfortunately, many people have diabetes without realising because the tell-tale signs do not necessarily make you feel unwell. According to the NHS , the main symptoms include: Peeing more than usual, particularly at night Feeling thirsty all the time Feeling very tired Losing weight without trying to Itching around your penis or vagina, or repeatedly getting thrush Cuts or wounds taking longer to heal . “A GP can diagnose diabetes. You’ll need a blood test, which you may have to go to your local health centre for if it cannot be done at your GP surgery,’ the health service explains.