The eyes have it - what your eyes say about your health

October 10th is World Sight Day. Their theme this year is universal eye health, and their aim is to move towards preventing avoidable blindness by making eye checks available to all. In the UK, it's easy to pop into a high street opticians and book a full assessment, ideally every two years, or more often if you're advised to. But all too many of us don't. Maybe we're put off by the cost - but what price your eyesight?

Your ophthalmic practitioner is trained to pick up a host of problems. These can be problems affecting the eye itself like glaucoma or cataract. But they can be a warning sign of more widespread problems. Flat, yellowish plaques on your eyelid can be a sign of seriously high cholesterol. A yellow tinge to the whites of your eye can signify the liver or blood problem jaundice. Examining the back of your eyes (retinal examination) can also pick up signs of complications from other conditions, like diabetes (type 1 or type 2) or high blood pressure.

Glaucoma can damage the nerve at the back of your eye because of raised pressure in the eyeball. It gets more common with age, affecting about one in 50 over-40s and one in 10 over-75s. There is a less common form called acute glaucoma, which causes severe pain, a red eye and sometimes blurred vision. This is a medical emergency. But chronic glaucoma often doesn't cause symptoms until it has already damaged your eyesight irreversibly - another good reason for regular eye checks. If you're over 40 and have a 'first-degree family history' (parent, sibling or child) of glaucoma, you're eligible for a free NHS eye test - tell your optician when you book your appointment.

Cataracts - clouding of the lens at the front of your eye which focuses images on the back of the eye - get more common with age. Occasionally they're present from birth, but are always looked for at routine baby checks with the doctor. Smoking, a poor diet, diabetes, certain tablets (including steroids and statins) and a family history all increase your risks. They're easily treated with surgery, but NHS funding restrictions mean that these days, you may not be eligible for referral until your vision is significantly affected.

Floaters (specks floating across your field of vision) may be nothing to worry about. However, occasionally they're a sign of detachment of the retina. If they're persistent or numerous - and especially if they're accompanied by bright flashing lights, blurred or distorted vision - get them checked out. Sore pink eyes with no acute pain and no problems with your eyesight are usually caused by harmless conjunctivitis (speak to your pharmacist about topical treatment). But an acutely painful or red eye; any sudden change in your eyesight; blisters or a rash on the skin around the eye; or pain that's increased by bright light should all be checked out by a doctor.

Your eyes perform incredibly complex tasks, translating light rays into meaningful messages sent to your brain. They complicated, they're fragile, and they can't be replaced. You wouldn't dream of driving the same car for life without a regular service - do your eyes deserve anything less?

Disclaimer: This article is for information only and should not be used for the diagnosis or treatment of medical conditions. Patient Platform Limited has used all reasonable care in compiling the information but make no warranty as to its accuracy. Consult a doctor or other health care professional for diagnosis and treatment of medical conditions. For details see our conditions.