More than two-thirds of young carers began looking after a family member before the age of nine, it has been revealed.
New research showed that about six out of 10 young carers are even responsible for the intimate care of a parent or sibling, including bathing.
Enda Egan of The Carers Association said there was a serious lack of awareness around the issue.
"With no support currently in place for young carers, we are asking the Government to implement cost-effective measures to help them in their caring role such as a dedicated young carers' website with information and forums," said Mr Egan.
Young carer Conor Hughes told a conference in Croke Park how he missed days in school and suffers from a lack of sleep.
The 18-year-old from Balbriggan, north Co Dublin, helps his mother, Angela, mind his two siblings -- sister Christina (15) who had a stroke in 2005 leaving her partially paralysed and his four-year-old brother Odhran who is autistic and has Asperger's Syndrome.
The teenager revealed his social life also suffered to the point where he had to give up playing sports as it clashed with hospital appointments.
Dr Allyn Fives, from National University Ireland, Galway, said teenagers who care for family members are forced into premature adult roles which has developmental implications.
But he added caring for a family member can also have positive impacts for young people.
"It can lead to greater maturity and compassion as well as closeness to the person cared for by the young person," he added.
"However, for some young people there can be negative impacts, including absence from or distraction while at school, feeling socially isolated, becoming ill, and experiencing feelings of boredom, worry and resentment."
Children's Minister Barry Andrews said the report gave an insight into the lives of young carers.
"While the report is preliminary and exploratory, it does mark an important milestone in improving our understanding of the positive and negative impacts for children who are involved in caring and makes a positive contribution to policy development and debate on this issue," he firstname.lastname@example.org