When you're taking on what medical journal The Lancet has branded "the biggest global health threat of the 21st century", it's a good idea to get some of the big hitters of the health world on your side.

Which is why we at 10:10 are overjoyed to announce that four key medical bodies had signed up to the campaign.

The Royal College of General Practitioners (RCGP), the Royal College of Nursing (RCN), the Royal College of Psychiatrists (RCPsych) and Great Ormond Street Hospital (GOSH), have all joined 10:10. As a result, tens of thousands of GPs and thousands of psychiatrists nationwide, GOSH’s 3,200 staff, and the RCN – the staff of which act for hundreds of thousands of nurses – will be encouraged to increase energy efficiency to reduce carbon emissions.

Dr Jane Collins, chief executive of Great Ormond Street Hospital, said: "I passionately believe that climate change is a serious threat to children's health, particularly in the poorer parts of the world.”

Talking about the current redevelopment at the world-famous children’s hospital, she added: “We hope GOSH's redevelopment will be as green as is practical for a city centre hospital. We have already started to audit and reduce our impact on the climate, but our commitment to 10:10 shows our determination to do more."

This is too big an issue to ignore.

Speaking on behalf of the RCGP – a network of more than 40,000 family doctors – Dr Tim Ballard said: "Climate change has rightly been identified as posing a significant risk to human health, and the RCGP is committed to promoting sustainable practice throughout primary care."

"We recently hosted our first-ever sustainability-themed annual conference, where the challenges facing not only GPs, but all healthcare professionals, and the public at large were discussed at length. This is too big an issue to ignore."

Professor Dinesh Bhugra

Meanwhile, Professor Dinesh Bhugra, president of the Royal College of Psychiatrists which represents 13,000 psychiatrists in the UK, highlighted the indisputable benefits of a low-carbon lifestyle. “Research shows a low-carbon lifestyle can improve mental health – which is why the RCPsych is proud to be playing its part in the 10:10 campaign,” he said. “People who engage in active, low-carbon activities, such as walking or cycling more often, are not only cutting emissions but keeping their bodies and minds healthy. For mild depression, physical activity can be as good as antidepressants or psychological treatments such as cognitive behavioural therapy."

He added: “Over the coming months, staff at the RCPsych will be working hard to cut our air and taxi travel, reduce our fuel consumption and make our eight offices across the UK more energy-efficient.

“Working together to tackle climate change could even help prevent harm to people’s mental health at an international level. Climate change as a result of global warming is likely to trigger increased flooding and greater risk of natural disasters across the world. As we have seen with the recent floods in Pakistan, these sorts of disasters can lead to destitution and poverty, which are associated with mental illness”

Dr Peter Carter, chief executive and general secretary of the RCN, which has 400,000 members nationwide, said his organisation had a duty to “lead the way” when it comes to energy efficiency. He said: “Better health is at the heart of the RCN’s work and it’s a natural fit for us to sign up to committing to reduce emissions. With temperature extremes, storms and flooding threatening health, organisations like ours need to do all they can to lead the way. We’ve already made a significant start in looking at our building management functions and in waste disposal, but in signing up to 10:10 we are now committing to go much further.”

With 10:10 sign-ups around the country discovering that cutting carbon can also lead to financial savings, the commitment of these health bodies has the potential to make all of us healthier and happier, and make our money go a little bit further.