A device, similar in size to a TV remote, is pointed at the upper arm, where a tiny implant is placed under the skin. This implant contains a reservoir of insulin that can last for ten days, Daily Mail reports.

As the sound waves hit the implant, they trigger it to allow small amounts of insulin to seep into the bloodstream. When the remote is switched off, the particles of the implant's surface close again, sealing the remaining insulin inside.

The technique, which has been tested on mice, could eventually mean thousands of diabetes patients no longer have to inject the hormone up to four times a day.

Type 1 diabetes tends to affect young people, who often need daily insulin jabs for the rest of their lives.

Type 2, which normally comes later in life, is often linked with sedentary  lifestyles. These sufferers are treated  with pills, though some end up needing jabs, too.

Karen Addington, chief executive of the charity Juvenile Diabetes Research Foundation, said a child diagnosed with type 1 diabetes at the age of five faces up to 19,000 insulin injections and 50,000 finger-prick blood tests by the time they are 18.

Scientists have been searching for ways to get insulin into the bloodstream without using needles. Some are developing insulin pills, while an inhaler was available in Britain between 2006 and 2008 before being withdrawn due to poor sales.

The latest approach could be an alternative solution. First, the small, round implant - the size of a mobile phone SIM card - is slipped beneath the  skin using a local anaesthetic. Inside each of its thousands of nanoparticles is a tiny amount of insulin.

When patients need an insulin boost, they hold the remote directly over the implant and press a button for 30 seconds. The sound waves make the particles vibrate and separate, releasing insulin. The treatment is being tested by scientists at North Carolina  State University.

Meanwhile, pistachio nuts may help with some symptoms of metabolic syndrome - an umbrella term for having diabetes, high blood pressure and obesity at the same time.