Around 12,000 adults in Ireland have been recorded as problem gamblers, with tens of thousands more recorded as being at risk from problem gambling, according to new ESRI Research.
The ESRI's Behavioural Research Unit said problem gambling has probably been underestimated.
However, the researchers said that the methods used to measure problem gambling are likely to underestimate it, perhaps substantially.
The study found that problem gambling is more prevalent among young men, people in disadvantaged communities and those with addiction issues and mental health problems.
It said many have difficulty perceiving their own gambling problems and recalling how much they have spent gambling.
The review found "reasonably strong" evidence that gambling advertising increases gambling.
It said evidence also shows that gamblers can be lulled into spending money on complex bets based on unlikely combinations of outcomes.
The ESRI said messages that encourage people to "gamble responsibly" are unlikely to be effective, based on current evidence.
Online social casino games and "loot boxes" in video games, which mimic online gambling and are "largely unregulated" could be correlated with layer gambling problems, the ESRI said.
It said there are "blurred lines" between social media and online gambling which are becoming more and more difficult to manage.
The review was commissioned through the Department of Justice and the Implementation Team supporting the establishment of the new Gambling Regulatory Authority of Ireland.
