The eyes are the windows of the soul, it is said. They are also windows to your health, as are your nails, hair, tongue and gums.

Their condition can be a warning sign of ailments from diabetes to cardiovascular and thyroid diseases.

Still, that eye discomfort or swollen gum, for instance, is only an indicator of the state of your health. It is best to let a doctor examine it for a proper diagnosis.

Dr A. B. John of A B John Ear, Nose and Throat Clinic and Surgery said that people should never self-diagnose based on such signs.

Referring to symptoms from the tongue, he said: 'Self examination may be confusing as the ordinary person, unless medically trained, does not know what a normal tongue looks like.'

Here are some symptoms to help you understand your body and perhaps prompt you to see a doctor.

Eyes

The blood vessels in the eye can indicate cardiovascular risk and stroke, said Associate Professor Leonard Ang, the medical director of The Eye and Cornea Transplant Centre and Premium Lasik Surgery Clinic.

Any abnormalities in the small blood vessels of the eye may be a reflection of the other small vessels elsewhere in the body, he said.

Prof Ang added that as the eye is the only organ in the body through which doctors can view these vessels non-invasively, any irregularities can be easily identified through an eye screening.

Stroke, for example, usually involves the small blood vessels.

It is thus prudent for people above 45 years old to have an annual eye screening so that these conditions can be detected and treated early, he said.

Tongue

In traditional Chinese medicine (TCM) practice, the tongue is one of the four essential methods of health examination, said Ms Miao Meng, a TCM physician at Raffles Chinese Medicine.

'In Western medicine, it is not emphasised as much but it is nevertheless important in a doctor's examination,' said Dr John.

If your tongue is red and painful, your body may lack iron or vitamin B12, said Dr Goh Yau Hong, a consultant ENT surgeon at YH Goh Ear Nose Throat, Head and Neck Surgery.

Dr John said that if you see sore spots on your tongue, it could indicate a zinc or an iron deficiency.

Both doctors said these conditions are easily treatable, provided you address the deficiencies.

Gums

Healthy gums are pink. Any deviation from this colour may be cause for concern. Pale gums, for instance, could indicate anaemia.

'A reduced blood flow or reduction in blood haemoglobin could cause the gums to be pale,' said Dr Ansgar Cheng, a prosthodontist with Specialist Dental Group.

Meanwhile, red and swollen gums could be a sign of diabetes as diabetics are about four times more susceptible to infections, he said.

However, these are also indicative of a dental condition, Dr Cheng said, so a proper examination is advised.

Dr Helena Lee, a periodontist at Specialist Dental Group, said that if underlying systemic diseases are suspected, she would refer patients to other medical specialists.

Nails

While slight nail imperfections could mean nothing, there are some nail appearances to look out for.

If your nails are pale, anaemia could be the cause.

Dr Joyce Lee, a consultant dermatologist at the National Skin Centre, explained that anaemia can cause a drop in red blood cells going to the blood vessels of the nail bed.

If your nails chip easily, this could point to a circulatory dysfunction, an iron deficiency or thyroid disease, said Dr Lee.

'Not all medical conditions are associated with nail changes and the signs should be taken in the context of the patient's other signs and symptoms,' cautioned Dr Lee.

Hair

Increased hair fall, known medically as telogen effluviumm, is a common manifestation of health problems, said Dr Tey Hong Liang, an associate consultant dermatologist at the National Skin Centre.Make a Mark in Your Career with a Top UK Hons Degree at Kaplan 

Long-term deficiency of iron and thyroid hormones can lead to generalised hair loss, he said.

Is your hair beginning to grey although you are still young? This could be due to a deficiency of selenium or copper, but it rarely happens unless you suffer from anorexia or serious gut problems, said Dr Tey.

A proper diagnosis is important and one should see a doctor to make sure that there are no serious underlying problems, he said.

staceyc@sph.com.sg

This article was first published in Mind Your Body, The Straits Times.