What do we really mean by ‘processed food’?

And how we’ve been taught to worry about the wrong things

Part One of a two-part series

When people hear the phrase ‘processed food’, they often picture fast food, plastic-wrapped snacks, or sugary drinks. But the reality is more complicated — and much more confusing than it needs to be.

In recent years, the clean-eating movement and wellness culture – with the help of corporate marketing departments trying to optimise perceptions of products that are not necessarily healthy – have shaped a widespread belief that anything processed is automatically bad for you. Buzzwords like ‘natural’, ‘clean label’, and ‘free from’ have flooded packaging and social media, reinforcing the idea that the healthiness of a product can be judged by how few ingredients a food contains or how many stages of processing it’s been through. This mindset has led many people to lump all processed foods together — leading to the idea that oat milk, chicken nuggets, tinned lentils, and gummy bears all fall into the same category, and that they’re all equally bad for us.

But processing isn’t new, and it isn’t inherently harmful. From cooking and drying to freezing, fermenting, and canning, we’ve been using processing techniques for thousands of years in order to make food safer, more nutritious, and longer-lasting. Everyday staples such as bread, hummus, and oat milk are all processed — there’s no way around that – but they’re not necessarily ultraprocessed.

Yes, there are many products that are high in sugar, salt, and saturated fats that are best eaten sparingly. But that doesn’t mean that you should treat all processed foods the same. It’s time to look beyond the marketing – and rethink what ‘healthy’ really means.

Processed, ultra-processed…or just misunderstood?

In the last two decades, researchers have developed various systems to classify processed foods. These include the widely used NOVA system, along with several other models developed by researchers and health agencies around the world.¹ These systems tend to group foods by how much they’ve been altered from their original form, how many ingredients they contain, or how ‘industrial’ the process was. But, crucially, they do not directly evaluate nutritional value.

That leads to numerous contradictions. For example, whole-wheat bread – widely considered to be a healthy, fibre-rich staple – is classified as ‘processed’ or even ‘ultra-processed’ in several systems, while lard – a pure saturated animal fat – is considered a ‘processed culinary ingredient’.^{2 3} Neither category reflects the health impact of the food itself.

Nutrients matter more than process

The World Health Organization recommends that saturated fats make up less than 10% of our energy intake in order to reduce the risk of heart disease and other chronic conditions.⁴ Whole-wheat bread generally supports this goal, while lard is more likely to undermine it – regardless of which product has a shorter ingredient list.

Similarly, classifying foods based only on the extent of processing can mislead consumers. A sugary white-bread bun and a fibre-rich seed loaf might both fall into the ‘ultra-processed’ category but they differ significantly in terms of their health impact. In short, from the scientific evidence we have at the moment, we can say that it’s the nutritional content that matters – not how many steps it took to make a food product.^{5 6 7 8}

So, are all ultra-processed foods bad?

It depends. The evidence linking the consumption of ultra-processed food to poor health is inconsistent. Many studies fail to account for nutritional differences between products, relying instead on short-term data or self-reported food diaries that are prone to bias.^{9 10}

However, there is a clear consensus that foods that are high in added sugar, salt, and saturated fats, and that are also ultra-processed – including both animal- and plant-based packaged foods – should be limited. These include processed meats, sugary drinks, crisps, and sweets. ¹¹

A recent review by the UK’s Scientific Advisory Committee on Nutrition concluded that the health risks linked to ultra-processed foods are difficult to separate from confounding factors such as socioeconomic status and broader dietary patterns. Consequently, the committee recommended caution in drawing firm conclusions based on current classification models alone.¹²

Processing isn’t the enemy

Processing can improve food safety, increase shelf life, and preserve nutrients. Frozen vegetables, for example, often retain more nutrients than fresh ones stored for several days. Processing also helps to ensure microbial safety in foods such as dairy, grains, legumes, and meat alternatives^{13 14}.

A 2023 study showed that it’s possible to meet all nutritional recommendations on a diet consisting almost entirely of foods that are classified as ultra-processed.¹⁵ Of course, that doesn’t mean we should aim for this – but it does show that processing alone doesn’t determine whether a food is healthy.

Let’s stay focused on what’s in the food we eat

Not all processed foods are the same. It’s the type of processing, the nutritional content, and the broader context of someone’s diet that matter most.

However, while it’s difficult to make a general statement about the nutritional value of processed foods, one thing is clear: we need a whole lot more nuance in the public conversation around food processing. Demonising whole categories based on vague labels confuses even well-educated consumers, distracts from the very real health risks of many ultra-processed foods, and can steer people away from convenient, sustainable, and fortified foods that could benefit their health.

So, let’s focus less on whether a product is processed – and more on what’s actually in the food we eat.

1. de Araújo, T. P., de Moraes, M. M., Afonso, C., Santos, C., & Rodrigues, S. S. (2022). Food Processing: Comparison of Different Food Classification Systems. Nutrients, 14(4), 729. https://doi.org/10.3390/nu14040729 ↩︎
2. Bread, whole-wheat, and commercially prepared. 2019. USDA, Available at: https://fdc.nal.usda.gov/fdc-app.html#/food-details/335240/nutrients ↩︎
3. USDA (2019): Lard. Available at: https://fdc.nal.usda.gov/fdc-app.html#/food-details/171401/nutrients ↩︎
4. WHO (2020): Healthy diet. Available at: https://www.who.int/news-room/fact-sheets/detail/healthy-diet [10.01.2024] ↩︎
5. Visioli, F., Marangoni, F., Fogliano, V., Del Rio, D., Martinez, J., Kuhnle, G., . . . Poli, A. (2022). The ultra-processed foods hypothesis: A product processed well beyond the basic ingredients in the package. Nutrition Research Reviews, 1-11. doi:10.1017/S0954422422000117 ↩︎
6. Jones JM. (2019): Food processing: criteria for dietary guidance and public health? Proceedings of the Nutrition Society. 2019;78(1):4-18. doi:10.1017/S0029665118002513 ↩︎
7. Srour B, Kordahi MC, Bonazzi E, Deschasaux-Tanguy M, Touvier M, Chassaing B. Ultra-processed foods and human health: from epidemiological evidence to mechanistic insights. Lancet Gastroenterol Hepatol. 2022 Dec;7(12):1128-1140. doi: 10.1016/S2468-1253(22)00169-8. Epub 2022 Aug 8. PMID: 35952706. ↩︎
8. Poti, J. M., Braga, B., & Qin, B. (2017). Ultra-processed Food Intake and Obesity: What Really Matters for Health – Processing or Nutrient Content? Current obesity reports, 6(4), 420. https://doi.org/10.1007/s13679-017-0285-4 ↩︎
9. Poti, J. M., Braga, B., & Qin, B. (2017). Ultra-processed Food Intake and Obesity: What Really Matters for Health – Processing or Nutrient Content? Current obesity reports, 6(4), 420. https://doi.org/10.1007/s13679-017-0285-4 ↩︎
10. Cordova R, Kliemann N, Huybrechts I, Rauber F, Vamos EP, Levy RB, et al. (2021): Consumption of ultra-processed foods associated with weight gain and obesity in adults: a multi-national cohort study. Clin Nutr. https://doi.org/10.1016/j.clnu.2021.08.00 ↩︎
11. WHO (2020): Healthy diet. Available at https://www.who.int/news-room/fact-sheets/detail/healthy-diet [04.01.2024] ↩︎
12. Independent report. SACN statement on processed foods and health – summary report. Published:11 July 2023. Available at: https://www.gov.uk/government/publications/sacn-statement-on-processed-foods-and-health/sacn-statement-on-processed-foods-and-health-summary-report ↩︎
13. WHO (n.d.): Why improving food safety is important. Available at: https://www.un.org/en/observances/food-safety-day [10.01.2024] ↩︎
14. Onyeaka, Helen et al. (2023): Global nutritional challenges of reformulated food: A review. Food science & nutrition vol. 11,6 2483-2499. 6 Mar. 2023, doi:10.1002/fsn3.3286 ↩︎
15. Hess, J. M., Comeau, M. E., Casperson, S., Slavin, J. L., Johnson, G. H., Messina, M., Raatz, S., Scheett, A. J., Bodensteiner, A., & Palmer, D. G. (2023). Dietary Guidelines Meet NOVA: Developing a Menu for A Healthy Dietary Pattern Using Ultra-Processed Foods. The Journal of Nutrition, 153(8), 2472-2481. https://doi.org/10.1016/j.tjnut.2023.06.028 ↩︎