Your eyes can reveal a lot about your health, not just your emotions. A quick glance or a subtle look can speak volumes, but to those with medical training, your eyes can disclose everything from cholesterol levels to thyroid issues.

If you notice a new bulge in your eye or an unusual coloured ring around your iris, it could indicate a serious health problem. While these symptoms may seem unrelated to your heart, liver, or thyroid, they can provide significant insights into your overall physical health.

Like any other organ, your eyes can exhibit changes when something is amiss elsewhere in your body. For instance, jaundice can turn the whites of your eyes yellow due to problems with the function of your liver, while also turning your skin a sallow yellow colour, reports Gloucestershire Live.

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However, there are many other severe health symptoms that can be detected by simply looking into someone's eyes. While many of these conditions are rare and unlikely to affect you, if you do spot any of them, it would be wise to consult your GP for further medical examinations.

Exophthalmos

Exophthalmos, or proptosis, is when your eyes bulge outwards
Exophthalmos, or proptosis, is when your eyes bulge outwards

Approximately 80 per cent of individuals with an overactive thyroid (hyperthyroidism) suffer from a condition known as Grave's disease. Despite the availability of surgical and medicinal treatments, some patients may experience their eyes beginning to protrude from their sockets.

Exophthalmos, or proptosis, is a condition where swelling around the eye, triggered by Grave's disease, causes the eye to protrude from its socket. Although it doesn't typically lead to vision loss and often resolves itself, many individuals may experience this for up to two years.

Grave's disease is an autoimmune disorder where the immune system attacks the thyroid gland, which regulates certain hormones, causing it to overproduce thyroid hormones. It usually affects both eyes, but some people may notice it more in one eye than the other.

The National Eye Institute explains: "Sometimes Graves' disease makes the immune system attack the muscles and other tissues around the eyes. This causes swelling behind the eye sockets, which makes the eyes bulge out.

"Researchers aren't sure what causes Graves' disease. They think people with certain genes may be more likely to get it. Viruses or something else in the environment may act as a "trigger" that makes the disease develop in people who have these genes.

"Graves' disease isn't contagious - you can't get it from or give it to other people."

Corneal arcus

A corneal arcus
A corneal arcus ring can be a red flag for high cholesterol

More common in middle aged and older people, if you notice a blue ring develop around someone's iris, it could be a sign that they have a genetic problem with cholesterol. The condition, known as a corneal arcus, is actually a tell-tale sign of a genetic disorder called familial hypercholesterolaemia.

Some people will get tested for this condition, affecting one in every 250 people, if a family member has a heart attack at a young age, as their liver might not be processing cholesterol properly. This can cause a variety of symptoms, including the arcus senilis, which presents as a white or blue ring.

This is not the only symptom of high cholesterol that you can spot just by looking into someone's eyes. For some people with this familial genetic condition can also cause them to develop xanthelasmas.

These are yellowy lumps near the inner corner of the eye that are actually small deposits of cholesterol. Elsewhere on your body, this can also cause xanthomata to form around your tendons - which can cause your knuckle to swell and become stiff due to the build-up of cholesterol deposits.

People with this disorder should seek medical advice as they will need to take steps to lower their cholesterol intake, or these symptoms can become worse.

The NHS says: "Nearly everybody with FH can be treated effectively with statins and other lipid lowering drugs. A small number of people with FH may require lipoprotein apheresis, or sometimes may be offered a new medication as part of a clinical trial."

Kayser-Fleischer rings

A Kayser-Fleischer ring

If you can see a rusty yellow-brown ring around your iris, your body could be storing up dangerous amounts of metal through a recessive genetic disorder known as Wilson's disease (WD).

WD is a rare disorder that causes copper to build up in several organs in your body, including your eye. This is called a Kayser-Fleischer ring, which begins as a yellow to green coloured line at the top of your iris, before developing into a ring.

The disease mainly affects the brain and liver, also causing swelling in the abdomen, yellow skin, and sometimes personality changes. The onset of WD can occur at any time, though mostly affecting those aged 3 to 50, and is tested for through a series of liver examinations and a visit to an ophthalmologist.

The British Liver Trust explains: "A characteristic clinical sign of Wilson’s disease is a rusty or coppery brown ring around your eye known as the Kayser-Fleischer ring (sometimes called the K-F ring). In most cases you can’t see the ring with the naked eye. Around half of people with Wilson’s disease have them.

"As part of testing for Wilson’s disease you will have a slit-lamp eye examination to check for Kayser-Fleischer rings. A doctor who specialises in the diagnosis and treatment of eye conditions (ophthalmologist) will do the test. The slit-lamp is a type of specialised microscope with a high-intensity light beam attached that gives the doctor a very close-up view of your cornea."

If you have any concerns regarding your health, please contact your GP or NHS' 111.