New Zealand's Dental Association are calling for tighter regulation on advertising sugary drinks on Facebook.
They say young people are being targeted by the adverts, causing challenges for those in public health advocacy and policy to reduce obesity.
The association are responding to an Australian and New Zealand Journal of Public Health study released this week which looked at engagement of people aged 13-25 with six of the top soft, sports and energy drinks Facebook pages.
The results showed there were almost 1.9 million engagements across the six pages over the six‐month period.
Around 70 per cent of the posts included encouragement for followers to respond with action.
Researchers reported that content by sports and energy drink brands were dominated by "sporting prowess" and "masculinity" themes. While content by Coca‐Cola shared the message of "having fun with friends" and "happiness".
NZDA sugary drinks spokesperson Dr Donna Kennedy said traditional advertising, such as TV, print and billboards can be seen by the public, health advocates, and regulators.
"Social media advertising can be more targeted to individuals, and it becomes difficult to monitor," Kennedy said.
The New Zealand Beverage Council responded by saying all its members had undertaken to abide by the Children's and Young People's Advertising Code, the Code for Advertising Food and the Advertising Code of Ethics.
"This means that our members do not advertise any beverage in media that directly targets children under-14, or where 25 per cent or more of the expected audience will be children under-14," NZBC spokesperson Stephen Jones said.
Jones said the study did not analyse the age of those engaging in the Facebook posts.
"The reality is that Facebook is used by people of all ages and we would expect people of all ages to be engaging with the Facebook posts of our member companies.
"In fact, in New Zealand more people over-65 have Facebook accounts than under-17, and the age-group with the highest Facebook usage is 25-34 year-olds.
He said there is nothing in the study that suggested further marketing regulation is required.
"New Zealand already has some of the most stringent marketing regulations in the world and we are confident that our members are abiding by these regulations."
This study comes at a time when DHBs are pushing to have a tax on sugary drinks - warning the obesity epidemic could result in Kiwi kids living shorter lives than their parents.
Letters sent to Health Minister David Clark were the strongest call for change so far from within a health system treating more obesity-related disease and tooth decay.
"For the first time in history, NZ children could live shorter lives than their parents as a result of excess weight and obesity," Andrew Blair, chair of both Capital & Coast and Hutt Valley DHBs, told Clark.
A NZDA spokesperson said from an oral health perspective, sugar was a big concern and the high acidity in sugary drinks that erodes teeth.