Ultra-processed foods (UPFs) are everywhere—from breakfast cereals, frozen meals and sugary snacks, to less obvious food items such as plant-based milk and sliced bread.
They’re convenient and often delicious, but they’re also a leading contributor to poor dietary quality in many Western diets. Research has suggested that a poor diet has overtaken smoking as the leading cause of early death globally. Could this shift in dietary patterns raise concerns about future life expectancy trends?
Given their negative connotations, is it possible to strike a balance and choose these items wisely? Let’s look at what makes these foods ultra-processed, why they’re potentially harmful and the practical implications.
What are ultra-processed foods?
“Processed food” is a term that is thrown around a lot in everyday life – in the media, by the government, by friends and family. Pretty much anyone you speak with will have a perception of processed foods.
Technically speaking, the majority of what we eat is processed. Most food undergoes some form of processing for us to consume it. For example, removing a pistachio shell is a ‘process’ the pistachio undergoes so that we can eat the nut inside. Therefore, some processed foods could be considered more nutritious than others.
The difficulty lies in the meaning – what is normally meant by ‘processed’ is ‘ultra-processed’, which has a different meaning and different connotations. There are different levels to how processed a food is, as classified by NOVA.
How are they classified and defined?
NOVA classifies food into four primary categories;
- Unprocessed or minimally processed
This includes products such as fruit, vegetables, animal products (meat, fish, milk, eggs), nuts, and seeds. These have no added ingredients and have undergone very little alteration from the state in which they are procured.
- Processed culinary ingredients
As the name implies, this group includes ingredients that are added to other foods, rather than consumed by themselves – for example, things like sugar, oil, or salt.
- Processed
This is where the confusion can sometimes lie.
‘Processed’ foods are typically those that are made from ingredients found in group one and group two, ‘processed’ easily within their own kitchens. For example, making jam or homemade bread, or pickling items to preserve them.
- Ultra-processed foods
UPFs are what people typically mean when they refer to ‘processed’ foods but are also commonly referred to as junk food. However, some more surprising items such as some plant-based milks technically fall into this category.
UFPs tend to contain five or more ingredients, some of which are typically used for preservation or to extend the shelf life of the product. E.g. preservatives, emulsifiers, stabilisers, artificial colours or flavourings, sweeteners, and so on. These are typically the ingredients that seem a bit more foreign to us.
Why are UPFs considered ‘bad’?
UPFs are said to harm health due to their high levels of added sugars, unhealthy fats, and artificial additives, which disrupt the body’s natural processes. UPFs are engineered for taste, leading to overconsumption and often containing fewer essential nutrients than whole foods.
This combination can increase calorie intake without providing satiety, leading to weight gain, obesity, and metabolic issues. Additionally, certain additives in UPFs, like emulsifiers, may impact gut health, promoting inflammation. Over time, a diet high in UPFs has been linked to a greater risk of chronic diseases, including heart disease, diabetes, and some cancers.
What does the research say about UPFs?
Research on UPFs reveals significant health concerns, particularly when these foods dominate a diet. However, looking at the research on a more granular level starts to put things into perspective and raises some questions.
First of all, research by Wang et al., (2024), showed that increased UPFs consumption was associated with multiple health outcomes. However, when you look into the research more closely, only two systematic reviews were rated moderate in terms of the quality of their methodology, with the rest being low or critically low. This suggests well-conducted systematic reviews with high-quality cohorts are needed to verify these findings. The same could be said based on the review by Lane et al., (2024).
Generally speaking though, extensive research on the effects UPFs on people is still in relatively early stages, though it has accelerated in recent years.
Some limitations include:
- Population Studies: Large-scale observational studies, such as those published in The BMJ and JAMA, have linked UPF consumption with higher risks of health conditions like obesity, cardiovascular disease, and cancer. These studies often involve thousands of participants, such as the French NutriNet-Santé cohort, which tracked dietary intake and health outcomes in over 100,000 adults.
While these studies show strong correlations, they cannot definitively prove causation due to confounding factors like lifestyle and socioeconomic status.
- Controlled Human Trials: More controlled trials on UPFs are emerging, but they are fewer in number and typically shorter in duration due to logistical constraints. A notable example is the National Institutes of Health (NIH) study led by Dr. Kevin Hall, where participants were randomly assigned to a UPF-heavy diet or a whole-food diet for two weeks. The study found that those on the UPF diet consumed more calories and gained weight. However, such short-term studies are limited in assessing long-term health impacts.
- Diet Quality and Behaviour: Some research focuses on dietary behaviours linked to UPFs rather than their isolated effects. Studies often note that diets high in UPFs tend to be lower in fibre, protein, and essential vitamins. However, individual responses to UPFs can vary, and long-term human studies that track outcomes over decades are rare. This makes it hard to form a complete picture of UPFs’ effects on health over a lifetime.
- Emerging Studies on Mechanisms: Some studies are beginning to explore the mechanisms of how UPFs impact health, such as their influence on satiety, gut microbiota, and metabolic responses. However, studies investigating these effects in humans are limited and sometimes inconclusive. This is often due to the complexities of human metabolism and diverse gut microbiota compositions.
In summary, while there is extensive observational research on UPFs and some short-term controlled trials, long-term, large-scale clinical studies on UPFs in human diets remain limited. The research we do have points toward risks with UPF-heavy diets, but more robust, long-term studies are needed to fully understand their impacts on human health across diverse populations.
What are the practical implications?
As emerging research highlights links between intake of UPFs and negative health outcomes, intake should be considered. However, it isn’t as black and white as it seems.
Author and dietician Nicola Ludlow-Raine has raised an interesting classification for UPFs in her book How not to eat ultra-processed:
- Minimally processed foods e.g frozen fruits and vegetables
- Ultra-processed and more nutritious foods e.g. fortified bread/cereals
- Ultra-processed and less nutritious or more calorie-dense foods e.g. pre-packaged confectionary items.
Therefore, if and when we include UPFs in our diet, try to choose those considered more nutritious. For example with bread – although sliced bread is considered processed, going for sliced wholemeal, over white bread is a beneficial choice due to the increased fibre intake in the wholemeal option.
In general:
- Base your diet on whole foods and minimally processed items as much as possible.
- Try to prep more at home (or let us help you with this).
- Try to check the ingredient lists on processed foods before buying them to help make more informed decisions. Opt for items with shorter ingredient lists where possible.
- If eating out, is there a more nutrient-dense UPF available or can you balance it out with a non-UPF drink or side? For example, swapping a ready-made salad dressing for something simple like a squeeze of lemon or some extra-virgin olive oil.
While high intake of some processed foods certainly raises health concerns, they shouldn’t necessarily be demonised entirely. It’s key to recognise the nuances in nutrition; seeing processed foods as simply “good” or “bad” can foster an unhealthy relationship with food. Ultimately, while whole foods are undoubtedly more nutritious, certain processed options can still fit into a balanced, flexible, and realistic diet.
Consider your diet as a whole – as long as UPFs aren’t forming the basis of your diet, having the odd item here and there is unlikely to have a negative impact on your overall health!
Fresh Fitness Food provides personalised meal plans delivered straight to your door, ensuring not only that you have the nutrients you need to keep you energised, but also that you have the time usually spent shopping, cooking and washing up, to engage in your favourite activities. Order today and start smashing your goals with personalised nutrition! To discuss which nutrition plan is right for you, book a call with our in-house nutrition team here.
Order today and start smashing your goals with personalised nutrition!
Get £50 off a 5-day trial with code: BLOG50. Start your trial here!
Save as PDF
