The Maori Party's attempt to have GST removed from healthy foods was defeated in Parliament on Wednesday night.
A member's bill in the name of Rahui Katene was rejected by 64 votes to 56, being opposed by the National, ACT and United Future parties.
Ms Katene told Parliament GST hits lower-income earners disproportionately because they spend a higher proportion of their income on food.
She says food prices have risen more than 20% in the past three years but real incomes have risen only slightly.
The Labour Party supported the bill, but says that if the Maori Party were serious about removing GST on healthy food, it would not have supported the Government's Budget, which raised GST to 15%.
National says defining what is healthy is too difficult.
Ms Katene and the other Maori Party MPs say the bill's defeat is not the end of the issue.