The number of children under the age of 16 who were hospitalised with anorexia almost doubled last year.
Freedom of Information figures, obtained by Newstalk, show 237 had inpatient admissions in public hospitals in 2021 - compared to only 121 the previous year.
Eating disorders, especially anorexia, have the highest death rate of all mental illnesses.
Professor of psychiatry at Trinity College Dublin, Brendan Kelly, says the spike in hospitalisations is probably linked to the COVID-19 pandemic.
"We saw an increase in certain kinds of mental illness and mental disorders during the pandemic, but particularly eating disorders and anorexia nervosa among young people.
"So it's disappointing to see this, but it might reflect more young people seeking help for what has been an under-recognised condition".
Prof Kelly says anorexia can have very serious consequences.
"Anorexia involves a series of behaviours, centred on not eating to a normal degree - and sometimes that can be quite extreme.
"So the reasons for hospitalisation can be owing to the mental health side of anorexia, but also physical health.
"If weight drops to a very sifincgant level, there can cardiac complications and other problems in the physical body".
Anyone affected by issues raised in this article can contact Bodywhys on 01-210-7906