The broader health benefits of optimised dietary thresholds proposed for type 2 diabetes prevention in Aotearoa New Zealand: simulation modelling.

Aim: Optimised dietary thresholds for type 2 diabetes prevention exist; however, they likely have additional benefits beyond diabetes prevention. We have modelled the effects of the proposed dietary thresholds on Health-Adjusted Life Years (HALY), health inequities and health system cost in Aotearoa New Zealand.

Methods: We created a national diet scenario using the optimised thresholds and compared it with current intakes using an established multistate life table. The primary model considered change in outcome from increasing intakes of fruits, vegetables, nuts and seeds while decreasing red meat and sugar-sweetened beverages. A separate secondary nutrient-based model considered change due to increasing whole grains and yoghurt while decreasing refined grains, potatoes and fruit juice. Both models considered the direct non-weight mediated associations between diet and disease.

Results: In the primary model, adopting the dietary thresholds produced clear benefit to Aotearoa New Zealand in terms of HALY (1.2 million years [95%UI 1.0-1.5]), and a health system cost saving of $17.9 billion (95%UI 13.6-23.2) over the population life course. HALY gain was at least 1.8 times higher for Māori than non-Māori. The secondary model indicated further gains in HALY for all population groups and health systems costs.

Conclusion: These striking benefits of altering current dietary intakes provide strong evidence of the need for change. Such change requires government commitment to an overarching food strategy in Aotearoa New Zealand to build supportive food environments that enable healthy choices at affordable prices.