Acting Prime Minister Winston Peters says he does not agree New Zealand should have a sugar tax, as suggested by the chair of two New Zealand DHBs, saying "people are capable of looking after their own lives".

The chair of both Capital & Coast and Hutt Valley DHB Andrew Blair wrote to Health Minister David Clark strongly calling for more efforts to be made to fight obesity-related disease and tooth decay, including introducing a sugar tax.

"We understand the difficulties with various lobby groups in this highly contentious space and would encourage you to be as proactive as possible, particularly in relation to sugar-sweetened beverages, including consideration of the introduction of a tax," Mr Blair wrote.

"Your commitment to school-based clinics and ensuring the strength of our health services will also assist us to support healthy communities and families ... this would be more effective when the environment supports fewer unnecessary sugar-sweetened beverages and energy drinks."

Speaking this morning to TVNZ 1's Breakfast today, Mr Peters said he does not support the introduction of a sugar tax, because "people are capable of looking after their own lives".

"It's a matter of education, it's not just sugar - it's a whole range of other things," Mr Peters said.

"If we want to turn back the potential tsunami of obesity that's coming, let's be frank and open and look at a whole lot of products that are not good for people and try to turn people around by education.

"To have some namby-pamby state say 'you can't have this, you can't have that' - it's not what we should be doing as a country ... we should be ensuring that people understand what's good for them and what's bad.

"If you want to go on an Evangelistic mission to turn people around without their consent, then you go right ahead."

After some gentle joking from Breakfast host Jack Tame about the issue, Mr Peters reasserted: "This is a serious matter".

"We should be out there trying to ensure that we give people the right information early in life and make good food cheap enough ... fruit and things like that," Mr Peters said.