New holistic approach to classify foods and guide policies : example of the Australian Nutrition Classification Scheme

Whereas non-communicable diseases are increasing all over the world, public policy initiatives propose actions to address dietary risk factors to the consumers, such as front-of-pack labelling mostly based on nutrient-based , food-based and dietary-based nutrition classification schemes (NCSs). However, those schemes do not align with nutrition science principles as they only assess a handful of isolated nutrients or components.

In the present article (Dickie, 2023), a team of Australian experts shares a new holistic approach mixing the nutrition classification and the level of process transformation, such as NOVA classification. The result of this new model encourages to propose holistic, precise, synthetic and innovative label to public policies to guarantee consumers a scientific and exhaustive front-of-pack labelling.

The existing methods of NCS are not fully satisfactory showing the need of a holistic approach to guide policies

Worldwide, policy makers are increasingly using nutrition classification schemes (NCSs) to assess a food’s health potential for informing nutrition policy actions. However, there is wide variability among the NCSs implemented (Dickie S, 2022),classified into three main categories : 1) nutrient-based NCSs; 2) food-based NCS, and 3) dietary-based NCS. Those methods use different algorithms based on the nutrient content or the purpose of industrial processing (additive, degree of transformation) and give only a partial overview of health quality of food items with differences explained by their calculations and scales.

In addition, the existing models have a binary and strict interpretation of what is “unhealthy”, missing often an exhaustive evaluation, as including the degree of processing (Monteiro C, 2008). Improving the existing models to give the best information for food-supplies choices of the consumer is therefore necessary.

Such NCS can be improved by applying a top-down holistic approach with assessment of degree of processing as the first step and application of upper thresholds for risk nutrients as the second step.

A new innovative NCS model involving a pairwise assesement with other classifications

A team of Australian experts suggest a novel food processing-based NCS for guiding policy actions, with an easy binary approach classifying foods as “healthy” or “unhealthy”, but more complex than reductionist ones based only on the content of nutrients without considering synergies and antagonisms or based only on the degree of processing.

The model combines level of processing (based on NOVA model) and nutrient thresholds. The validity of this scheme was evaluated by classifying food and beverage items in the Australian food supply (face validity ) and comparing them to the classifications of existing NCSs (convergent validity ), using the scientist validation of NCs models (Cooper S, 2016 ; Mozaffarian D, 2021). For example, the model classified most of the food items in closest alignment to NOVA, with an agreement around 90%.

A higher proportion of food categories consistent with dietary patterns that are associated with positive health outcomes (fruit, vegetables and eggs) were classified as healthy while most of food categories associated with adverse health outcomes were classified as unhealthy, which is consistent with most of national dietary guidelines (Herforth A, 2019).

Those results confirm that NCSs should be led by a holistic approach with all the dimensions of nutrition: nutrients and their thresholds, and markers of ultra-processing (MUPs) as proxies to identify ultra-processed foods. The knowledge of the MUPs is necessary and may be updated to guarantee the stability of the model, which requires transparency and partnership with food industries.

The novel food processing-based nutrition classification presents a valid alternative to existing methods

This novel model built to guide public policies considers some limitations identified in existing NCS methods such as ambiguous food category classification and the assessment of certain nutrients such as total fat, and thus penalising whole foods. Most of food and beverage items were scanned with this new model.

Thus, results confirm that, although the model can be improved, it should be helpful for the consumers with an easily understood front-of-pack label. Indeed, a top-down holistic approach with the degree of processing as a first step, provides a NCS that may prevent ultra-processed foods from being promoted or evading regulation.

The novel NCS represents an improvement over existing models as it avoids overly strict interpretation of what is considered “unhealthy” and indicates strong face and convergent validity against existing NCSs.

Thus, a NCS model combining processing level and nutrient criteria could be a valid alternative to classify the health potential of individual foods for policy purposes.

Based on: Dickie S, & al. A novel food-processing-based nutrition classification scheme for guiding policy actions applied to the Australian Food Supply. Frontiers in Nutrition, 20 january 2023.