A new device can detect blood sugar levels in tears, meaning that diabetics could be saved from having to test their blood several times a day.

Currently, diabetics have to test their blood sugar levels anything from two to 10 times a day by drawing a droplet of blood with a finger-prick test.

This is the only way to safely monitor blood glucose and let diabetics know if they need an insulin injection.

However some people find this sore and uncomfortable so don’t test their blood as often as they should.

But researchers at the University of Michigan found that glucose levels in tears correlated to glucose levels in the blood – and they have now developed a sensor that can measure blood glucose in tears instead.

The researchers said in the journal Analytical Chemistry: “It may be possible to measure tear glucose levels multiple times per day to monitor blood glucose changes without the potential pain from the repeated invasive blood drawing method.”

Doctors say that there is a great demand for an alternative to using needles to test blood as fingers can become sensitive over time and there is always a small risk of infection.

Diabetes currently affects 2.8 million people in the UK and 26 million people in the US.