The RCN has called on 'proper community services' to support the soaring number of unpaid carers in the UK.
The number of unpaid carers has increased by 600,000 since 2001 to 5.8million, according to figures from the Office for National Statistics.
The findings reveal a 'growing army' of nearly 4,500 people spend more than 50 hours a week providing free care for family or loved ones.
Peter Carter, chief executive and general secretary of the RCN said: 'These figures will come as no surprise to anyone working in health care, as the increasing demands of an ageing population are all too apparent.
'We need to ensure the support is in place for the millions of people caring for family or friends. Carers make an invaluable contribution but they can experience physical health problems and stress related illnesses as a result of their responsibilities. They need independent advice, access to support and respite which can be offered through community health care services.
'Unpaid carers make huge sacrifices and there must be proper community services in place to support them and the people relying on their care.'