Ultra processed foods and their inputs increasingly dominate New Zealand’s food and beverage imports: a retrospective analysis

International trade and investment liberalization impact national food environments via changes to the availability and affordability of foods, and may encourage the trade of ultra-processed foods (UPF). This study describes New Zealand (NZ) food and beverage imports over time, in terms of their level of food processing. United Nations Comtrade data was gathered for years 1990–2023. All Harmonized System (HS) codes related to food or non-alcoholic beverages (N = 898) were categorized according to the Nova classification system into unprocessed and minimally processed foods (G1), processed culinary ingredients (G2), processed foods (G3) and UPF (G4). The food-derivatives/additives (e.g. industrial sugars and modified oils, flavourings, texture enhancers) that are UPF inputs were classified as a subgroup of G4. Total and per capita (p.c.) imports (by volume) were calculated for all years by Nova group and subgroup. Annual tariff rates from 1996 to 2023 were obtained from the World Trade Organisation Tariff & Trade Data platform. The share of G4 in total food and beverage imports increased over the study period, from 15.7 kg p.c. (8.7% of food imports) in 1990 to 103.8 kg p.c. (21.8%) in 2023. Of all G4 subgroups, the p.c. import volume of food-derivatives/additives (UPF inputs) increased dramatically since 1990, surpassing all other UPF subgroups since 2011. Other Nova subgroups with notable import growth included wheat cereals and flours (G1), plant oils (G2), processed vegetables and fruit (G3), and sweetened/flavoured drinks (G4). Tariff rates were reduced to zero or low levels for all food products between 1990 and 2023, with notable reductions around 1996-98, and 2007/08. Tariffs were generally higher on G3 and G4 product subgroups than G1 throughout the study period, though the difference was minimal. The 34 years of progressive trade liberalization in NZ were characterised by an increasing proportion of imported products being ultra-processed foods/beverages and their inputs, underscoring the need for policy interventions to counteract the impact of these trends on food environments and population nutrition.