Sundborn said sugary drinks were the single biggest contributor of sugar to people's diets, making up about 26 per cent of the sugar intake of children and about 20 per cent for adults.
Because of that, he believed a tax on sugary drinks was needed in New Zealand.
"By targeting that one product you're targeting the biggest contributor of sugar."
Auckland University's Dr Simon Thornley, a member of the New Zealand Beverage Guidance Council set up by FIZZ, said the group had looked at the research and concluded a tax on sugary drinks would help reduce the purchase of them.
The panel believed a tax of between 50 cents and $1 per litre would have a big enough impact to make a difference, he said.
Thornley too compared sugar's harmful effects to tobacco saying it was hard to convince people it was a killer.
"I firmly believe that sugar is addictive, that people get used to a higher level of intake then they get withdrawal symptoms and it's difficult for them to come off it and that's what you see with tobacco."
University of Colorado Professor Richard Johnson, a keynote speaker, agreed.
Not only was sugar an addictive substance which had serious health effects when consumed in large quantities, but he believed the sugar industry had tried to create doubt about its health effects in the same way the tobacco industry did.
Despite some assertions, sugar was not an empty calorie but had biological actions, he said. When sugar was metabolised it caused an organism to eat more and exercise less.
He agreed a sugar tax was an effective way of reducing people's intake.
University of California Berkley Associate Professor Kristine Madsen, who will speak at the symposium via video link, was senior study author for a project which monitored the impact of a sugary drinks tax introduced in Berkeley in March 2015.
The study showed a 21 per cent drop in the drinking of sugary beverages in the city's low-income neighbourhoods after the penny-per-ounce tax was imposed.
Coca-Cola Oceania general manager Sandhya Pillay said sugar and tobacco were entirely different because tobacco was harmful when consumed at any level but sugar was fine in moderation.
She said the company opposed a "discriminatory sugary drink tax" because current analysis indicated it had "no measurable impact on reducing obesity".
Coca-Cola had been actively promoting the new Coca-Cola No Sugar and a third of sales in New Zealand were now low or no sugar, she said.
Health Minister Dr Jonathan Coleman said the party's position on sugar tax hadn't changed and was not something being considered.
"We are continuing to keep a watching brief on the emerging evidence and practice. There's no single solution that will fix obesity. That's why we've implemented a Childhood Obesity Plan."
Taxing Sugary Drinks: An Election Issue
When: Monday June 26 from 8.50am to 4.15pm
Where: Auckland University Medical School, Grafton
Topics: Is sugar the new tobacco by Professor Richard Johnson; Are artificially sweetened drinks safe by Dr Lisa Te Morenga; Sugar coated kids by Dr Caryn Zinn; Just say ShFat that by Kate Sawyer and team; Political Panel Discussion on sugary drinks tax.
