The Irish Heart Foundation has called on the Government to match new regulations in the UK banning daytime TV and online adverts for junk foods, in what the British government called a "world-leading action" to tackle childhood obesity.
The ban - targeting ads for products high in fat, salt or sugar - is expected to remove up to 7.2 billion calories from children's diets each year, according to the UK health ministry.
Impacting ads airing before the 9pm watershed and anytime online, it will reduce the number of children living with obesity by 20,000 and deliver around £2 billion (€2.2bn) in health benefits, the ministry added.
The Irish Heart Foundation's director of advocacy, Chris Macey, said implementing similar restrictions here would be "a crucial measure for children's future health".
He said the current "lax rules" do not offer enough protection to children in Ireland.
"Children in Northern Ireland will now have greater protection than their counterparts here from unscrupulous online targeting tactics by junk brands that we know are rampant," Mr Macey said.
"They result in overconsumption, which in turn causes high rates of overweight and obesity that are damaging children's long-term health."
He said there have been a number of policy recommendations, most notably from the Oireachtas Committee on Children and Youth Affairs, that had the potential to curb the impact of marketing on children's food choices, but they have not been implemented.
"The implementation paralysis of successive governments, which have been well aware of the need for tough restrictions on junk food marketing, has to end. The futures of tens of thousands of today's children depend on it," Mr Macey said.
"The UK regulations still allow brand ads and we know that infants as young as 18 months can recognise brands. They also don't address influencer marketing which is playing a rapidly increasing role in junk food promotion.
"However, the new law is very much a step in the right direction and an essential part of action urgently need here to protect the long-term health of our children."
Tooth decay leading cause of UK hospital admissions for young children
The implementation of the measure in the UK - first announced in December 2024 - follows other recent steps, including an extended sugar tax on pre-packaged items like milkshakes, ready-to-go coffees and sweetened yoghurt drinks.
Local authorities have also been given the power to stop fast food shops setting up outside schools.
The government argues evidence shows advertising influences what and when children eat, shaping preferences from a young age and increasing the risk of obesity and related illnesses.
It notes 22% of children starting primary schooling in England - typically aged around five - are overweight or obese, rising to more than a third by the time they progress to secondary schools aged 11.
Tooth decay is the leading cause of UK hospital admissions for young children, typically aged five to nine, according to officials.
"By restricting adverts for junk food before 9pm and banning paid adverts online, we can remove excessive exposure to unhealthy foods," Britain's health minister Ashley Dalton said in a statement.
He added the move was part of a strategy to make the state-funded National Health Service (NHS) focus on preventing as well as treating sickness, "so people can lead healthier lives".
Executive Director of the Obesity Health Alliance Katharine Jenner said it was "a welcome and long-awaited step towards better protecting children from unhealthy food and drink advertising that can harm their health and wellbeing".
The charity Diabetes UK also welcomed the ads ban, with its chief executive, Colette Marshall, noting that type 2 diabetes is on the rise in young people.
"Obesity is a major risk factor for type 2 diabetes, and the condition can lead to more severe consequences in young people - leaving them at risk of serious complications like kidney failure and heart disease," she added.
