The NHS must take the lead in becoming a 'good corporate citizen', adopting policies and personal habits such as encouraging cycling and reducing waste to help beat global warming.
A new guide published last week by the Faculty of Public Health, backed by 19 organisations including the NHS Confederation, sets out how organisations and individuals can create a "virtuous circle whereby public health would be improved and the burden on the health service eased".
Co-author Jenny Griffiths, a former NHS chief executive and a fellow of the faculty, said that as one of the largest employers in the world the NHS is in a "unique position to take the lead" on climate change.
"People can feel helpless in the face of such a huge and overwhelming issue, but there is plenty that they can do - both as individuals and [as] part of their organisations."
Dr Griffiths said examples range from walking or cycling instead of using a car and taking care not to leave electrical appliances on standby, right up to carrying out a carbon audit, making sure environmental impact assessments become a routine part of all activities and developing a robust action plan.
She added: "We in the health service are in a unique position to use the NHS's immense influence and purchasing power to lead by example. If we do not act now, the consequences are unthinkable."
Sustaining a Healthy Future: taking action on climate change contains checklists for action by individuals, organisations and communities as well as a sustainability and health-check tool for all policies and strategies, examples of good practice and a list of useful organisations.