Experts reveal the one subtle warning sign of diabetes that can strike YEARS before other symptoms

Feeling dizzy or faint when you stand? You could be at risk of developing diabetes in the future, a study suggests.

Hungarian researchers claim they've found that patients at risk of Type 2 diabetes are up to six times likelier to have nerve damage that affects the heart, linked to condition.

Signs of this damage, called neuropathy, include feelings of faintness and dizziness, and can be picked up 'several years' before diabetes is diagnosed, the experts claim. 

Neuropathy is a medical term meaning damage to the nerves and is already a known complication of diabetes.

However, the researchers, from Semmelweis University, say patients are showing subtle signs of this damage even before their diabetes becomes fully developed.

Feeling dizzy or faint when you stand? You could be at risk of getting diabetes a study suggests (stock image)

They claim their findings could be used to track signs of neuropathy in patients at risk of diabetes and then either slow or prevent the nerve damage from occurring.

Neuropathy is a common complication of diabetes due to the way high blood sugar levels damage the small blood vessels that feed the nerves.

Over the long term this can lead nerve damage and can lead to different symptoms depending what nerves are affected.

It commonly results in what is called peripheral neuropathy which causes numbness, tingling, burning sensations, aching, cramps, and weakness in the feet and hands which can eventually spread to the entire limb. 

Other types of neuropathy that diabetics can suffer from include problems with their senses, the signal their organs receive and the ability to control their hands. 

In their study, published in the journal Frontiers in Endocrinology, researchers found people at increased risk of diabetes had 5.9 higher odds of having a type called parasympathetic neuropathy when compared to healthy people.

Parasympathetic neuropathy is type of damage to the nerves that govern how our body rests, for example sending signals to lower our heartbeat.

Cardiac autonomic neuropathy (CAN), a type of nerve damage relating to the heart, was specifically highlighted in the study as being more common in the at risk of diabetes group, again 5.9 times. 

CAN symptoms include an inability to exercise for more than a very short period of time and low blood pressure that can make you feel dizzy or faint when you stand up, according to the NHS. 

Researchers said they also found higher incidence of sensory neuropathy in the at risk group, but added this was observed in found in patients in the study. 

Study author Anna Körei, an assistant professor of medicine and oncology at Semmelweis, said: 'We were looking for signs of neuropathy in patients with normal blood glucose levels but with a higher risk of developing diabetes.

'We took a step back in time and looked at an earlier stage, where risk factors might be present but there's no clear indication of (pre-)diabetes.'

They study compared health test results of 44 people assessed as being at high risk of developing diabetes and 28 healthy controls.

Participants had their heartbeat measured, as well as tests on how their bodes reacted to sensations such as aching and burning pain, numbness.

Concluding their study the authors said their findings warrant further research.

The authors acknowledge their study had several limitations the most important being the small number of overall participants.

Another factor was that while participants were asked to stop taking medications that could influence the results, the authors couldn't guarantee they had followed this instruction. 

Approximately five million people in the UK are living with diabetes, of which an estimated 850,000 are unaware they have the condition. 

A recent report from Diabetes UK suggests there has been a staggering 39 per cent rise in type 2 diabetes in people under 40 in a trend that's been blamed on rising obesity levels. 

There is no cure for neuropathy linked to diabetes, however drugs are available to combat the symptoms it causes.

Problems with nerves that help detect pain in the feet is one reason that diabetics are advised to check their feet frequently as they may not feel wounds that can become dangerously infected.