Encouraging people to self-diagnose via the NHS Choices website saves the health service millions of pounds every year, according to a newly published study.

There were more than 100 million visits last year to the site, which offers patients a quick reference guide to illnesses, symptoms, diagnosis and treatment.

Overall, there was a 10% increase in the number of visits to the website in 2010 compared with 2009.

Some 19 million people logged on to NHS Choices for information on swine flu.

A study from Imperial College London found 70% of patients use the internet to search for health information, with a third deciding there is no need to visit their GP afterwards.

Reductions in avoidable and unnecessary consultations among young people could amount to savings of about £44m per year, it said.

The NHS Choices site has space for patients to write comments about hospitals and GP surgeries, and more than 40,000 comments have been posted so far.

Health minister Simon Burns said: “Every day we use the internet and technology to organise our lives, and increasingly when it comes to our health.

“For example, more and more people are taking the information they have found online with them when they consult their GP.

“It is important they can find accurate, trusted information from sources such as NHS Choices.

“It is vital that every penny spent on the NHS counts, and the Imperial College research shows that tools like NHS Choices can help deliver savings.”