More than a third of young people in Ireland are drinking sugary soft drinks most days of the week, research shows.
Men and people from poorer backgrounds are also more likely to regularly consume colas and lemonades blamed for feeding the country's growing obesity problem, the study reveals.
The findings will be a key focus at a cross-border conference in Belfast on Tuesday to mark World Obesity Day.
Dr Joanna Purdy, of the Institute of Public Health in Ireland, will tell the conference that figures from the Revenue Commissioners show more than 400 million litres of soft drinks are downed across the country every year.
"World Health Organisation guidelines state that free sugars should comprise less than 10% of our daily energy intake while reductions below 5% - around six teaspoons a day - would provide additional health benefits," she said.
"Consuming one 330 millilitre can of a sugar-sweetened drink could take a child over their recommended daily sugar intake."
The conference will hear that:
:: More than a third of 15 to 24-year-olds and more than one quarter of 25 to 44-year-olds drink sugary soft drinks every day or most days.
:: Some 58% of all those aged 15 and over consume soft drinks.
:: Almost half of 13-year-olds surveyed said they had a soft drink in the previous 24 hours - 53% of boys and 42% of girls.