A recent review published in Public Health Nutrition has found that many tools used to measure the sustainability of diets fail to consider the impact of industrial food processing, particularly ultra-processed foods. The review analyzed 57 peer-reviewed studies and found that about 65% did not include food processing in their assessment methodologies.
Researchers noted that while most existing tools account for agricultural production and final consumption, they often neglect other important aspects such as social equity and economic accessibility. Environmental and health metrics are typically prioritized instead. The study suggests that current methods may overlook the energy use and waste generated by ultra-processed foods, which have become increasingly prevalent in modern diets.
The review highlighted a lack of consensus on what constitutes a “sustainable diet,” with much of the debate focusing on plant-based versus animal-based eating patterns. This has influenced dietary recommendations like those from the EAT-Lancet Commission, which primarily address farming practices and human health outcomes.
Critics argue that these approaches do not reflect the full complexity of today’s food systems, where industrial manufacturing plays a significant role. Ultra-processed foods have been linked to rising rates of chronic diseases and are known for their resource-intensive production processes.
To investigate whether sustainability measurement tools adequately capture these issues, researchers followed PRISMA-SCR guidelines to select relevant publications from major scientific databases. Each included study was evaluated for how it addressed food production, storage, processing, retail distribution, and waste generation. The analysis also looked at which dimensions of sustainability were considered: environmental impact, nutritional quality, affordability, tradition, and acceptability.
Studies were grouped based on whether they directly or indirectly assessed food processing. Additionally, the review checked if studies used the NOVA classification system—a widely recognized method for categorizing foods by level of industrial processing.
Findings revealed that while nearly all studies provided detailed assessments of farming and dietary intake stages, over half (64.9%) omitted considerations related to industrial processing. Only 19.3% specifically developed or analyzed tools to include processing metrics or classify foods by degree of processing; just 8.8% used terms like “ultra-processed” or incorporated NOVA into their analyses.
There was also a notable difference in how various types of foods were tracked: almost all studies monitored fruit consumption (98.2%), but only 17.5% applied similar tracking to discretionary or ultra-processed foods.
The review pointed out imbalances in coverage across different aspects of sustainability—while health and environmental effects were always examined, fewer than one-quarter addressed economic or social factors (24.6% each), and less than half looked at cultural dimensions (42.1%).
Geographic representation was another concern: nearly three-quarters (73.7%) of reviewed studies focused on high-income countries with little attention paid to low-income regions where dynamics around food processing may differ significantly.
According to the authors: "Moving forward, the researchers call for integrating the NOVA classification into sustainability indices and Life Cycle Assessments (LCAs), without which future sustainability assessments risk promoting diets that may look green on paper but support an industrial system that is anything but."
The findings suggest there is a need for more comprehensive frameworks capable of evaluating not just what people eat but also how their food is produced—including its journey through complex industrial processes—so as to provide more accurate measures of dietary sustainability.
