Dr Rachael McLean made the point during her public talk on campus yesterday, titled "Pure, white and deadly''.
This reduction has been identified by the WHO as one of nine key voluntary global targets for the prevention and control of non-communicable disease.
The Dunedin talk reflected on New Zealand's efforts to achieve the WHO target of reducing the country's overall population salt intake by 30% by 2025.
Excessive salt intake contributes to higher blood pressure, and increases the risk of heart disease, stroke and some other diseases.
Dr McLean discussed recent research examining salt levels in takeaway and fast food, and food labelling, and said salt content in fast food remained too high.
A "comprehensive salt reduction strategy'' needed to be implemented.
"We're not going to reach it, doing what we're currently doing,'' she said.
A wider range of specific salt reduction targets for various food products was needed, and the Crown could also do more, including by establishing a unit at the Ministry of Health to, among other things, provide more support to the Heart Foundation over this issue.
Dr McLean said food manufacturers had a moral obligation to reduce the amount of salt in processed food products, given the risk of premature death and reduced quality of life among their customers.
Some New Zealand firms had already reduced their salt content, and several multi-national firms, including Nestle, had also pledged to further reduce salt content.
