A cheap supplement could help prevent potentially deadly heart failure among patients with type 2 diabetes, research suggests.

More than 5million people in the UK are thought to suffer from type 2 diabetes, which is often referred to as a 'silent killer', with rates having soared in recent years. 

But now scientists have found patients taking a substance called mitoquinone—sold as a health supplement for about 90p per tablet—had healthier hearts than those in a control group. 

Scientists behind the study said the results could save lives given how patients with type 2 diabetes have five times the risk of suffering heart failure compared to someone without the condition. 

In the trial, patients on mitoquinone even had signs that the damage their hearts had suffered from diabetes had been 'reversed'.

However, experts have said while their findings are promising they now need to be backed up by larger trials.

Mitoquinone is an artificial antioxidant—a substance that helps protect cells—which is a modified version of an antioxidant naturally found in the body called CoQ10.

Dr Henry Procter, an expert in heart health at University of Leeds and lead author of the four month study, said the results were 'encouraging'. 

'If the study had continued for longer, it is likely we would have started to see differences in more serious indicators of heart health between the group with mitoquinone and the group without,' he said. 

'We hope that a larger study will continue to demonstrate the benefits of this antioxidant, and that one day soon diabetic patients can be prescribed it to help prevent heart failure before it ever affects their lives.' 

In the trial, the results of which were presented at the British Cardiovascular Society conference in Manchester, involved 70 patients with type 2 diabetes without heart failure.

Half were given 40mg of mitoquinone per day in addition to their regular diabetes treatment, while the other half just received their usual medication.

Both groups had their heart health assessed at the start of the study and again four months later. 

At the end of the trial the group on mitoquinone were found to have hearts that performed 15 per cent more efficiently than at the start of the study.

The mitoquinone group were also found to have improvements in exercise tests, with their hearts also able to relax more quickly after exertion. 

Researchers said these were signs that the stress and stiffness the organ suffers from diabetes had been reversed.

Diabetes damages the heart by interfering with how the organ processes and uses energy.

Over time this interference causes stress and harms the cells of the heart muscle, leading to it becoming stiff and having to work harder to pump blood around the body, increasing the risk of heart failure. 

Mitoquinone is thought to help protect the cells from this damage. 

The substance is sold online as a health supplement for about £50 for a jar of 60 pills, which works out at about 86p per tablet. 

However, these are at doses far lower than those used in the study.

Critically, no adverse side effects were reported in the group taking mitoquinone.

The scientists are now hoping to run another similar trial with a larger group of patients to add more weight to their findings. 

If the results are supported by future studies the experts hope diabetes patients could one day be prescribed mitoquinone to help protect their hearts for longer. 

Heart failure is an incurable condition where the organ can’t pump blood around the body as well as it should.

The condition tends to get worse over time and is often eventually fatal. 

Once a diabetes patient is diagnosed with heart failure it triples their risk of dying within the next five years. 

Reacting to the study, Professor Bryan Willians, chief scientific and medical officer at the charity the British Heart Foundation, said it was a promising start.  

'It’s still early days for this research and the results will need to be confirmed in a larger scale trial,' he said.

'The study neatly demonstrates why it is so important to continue to support research and look for solutions in a wide variety of places, so that we can continue to offer hope to people living with, and at risk of, cardiovascular disease.'

Almost 6million Britons have diabetes, of which 90 per cent is type 2, but charities estimate 1.2million are living with the disease undiagnosed.

While nationally, an estimated 8 per cent of the population of England has the disease, this rises to over one in 10 people in some parts of the country. 

Type 2 diabetes occurs when the body doesn't make enough insulin or the insulin it makes doesn't work properly. Insulin is a hormone critical to controlling blood sugar levels.

Having high blood sugar levels over time can cause heart attacks and strokes, as well as problems with the eyes, kidneys and feet. 

Sufferers may need to overhaul their diet, take daily medication and have regular check-ups.

Symptoms of the condition, which is diagnosed with a blood test, include excessive thirst, tiredness and needing to urinate more often. But many people have no signs.