What's the truth about UPFs? 18 months on, a nutritionist evaluates

Headlines state that the risks associated with UPFs are stronger than ever. But after two decades in nutrition, I’ve learnt that food science is rarely clear cut. While many of us want to avoid UPFs, there remains a fair amount of confusion over what one actually is, and experts are urging for a clearer definition.

A number of countries advise reducing or avoid UPFs. However, a recent Scientific Report states that while UPFs may cause health issues, the evidence was ‘difficult to assess, largely because of the lack of clear definition of ultra-processed foods.’

What are UPFs?

Put simply, UPFs are foods that have been industrially processed and formulated using ingredients that aren’t available to us at home.

There is also NOVA which classifies foods into different groups. Although this has been criticised for being too broad and including other manufactured foods in the definition of UPFs.

The NOVA classifications are:

1. Unprocessed or minimally processed

These are natural foods which have been processed only to remove inedible parts (such as shelling or peeling), or perhaps freezing, cleaning or drying. For example, eggs and flour.

2. Processed culinary ingredients

These foods are used as an ingredient to prepare, season or cook other foods. Examples include vegetable oils, butter and lard, sugar and molasses.

3. Processed food

Foods that have added ingredients or use preserving methods like canning, curing and bottling. These may include tinned fruit and vegetables, cured or smoked meats and fish and some cheeses.

4. Ultra-processed food

These are made from substances that have been extracted from foods or synthesised in a laboratory; they include carbonated drinks, flavoured yogurt and mass-produced bread.

These groups do create some issues, for example powdered milk (group 1) is considered less processed than olive oil (group 2). What’s more, examples of ultra processed foods have varied over time. One example is both wholemeal sliced packaged bread and a white sliced packaged bread are classed as UPFs but the first has significantly more nutrients and fibre.

These anomalies occur because NOVA doesn’t take account of the nutrients in a food including fibre. It also does not advise on portion sizes or frequency of consumption.

What was the early advice around UPFs?

UPFs make up a significant part of our diets but with mounting evidence suggesting they cause health issues, advice was to cut back. However, UPFs can be convenient and often cost less. Although well-intentioned, this advice didn’t take into account that for some people, UPFs offer an affordable, accessible option and for those with time restrictions they serve as a convenient alternative.

What do we currently know?

Processing changes the structure of food. This determines how healthy a food is (along with other aspects such as added sugar and salt). However, it’s not a simple equation. For example, the packaged wholemeal loaf bought from your local shop may be considered group four – but can still represent an important source of fibre and B vitamins and consequently carry less risk to health than a group three or even group two food.

While studies have linked high consumption of UPFs with health issues such as obesity, type 2 diabetes, heart disease, certain cancers and increased mortality rates, these are largely observational. Which means they involve researchers asking people about their diets and assessing their health for a period of time. Although insightful, these studies make it difficult to understand the impact of overall diet and lifestyle.

So where does this leave us?

Currently, we don’t know if it’s the lack of nutrients in UPFs or high levels of fat, sugar and salt that causes health issues. Perhaps it’s the change in the food’s structure, or the impact on our appetite or gut microbiome? Or maybe it’s the use of additives such as emulsifiers, colours and flavourings? Or is dependent on whether someone smokes, drinks alcohol or leads a sedentary lifestyle?

Some studies have even suggested that the type of UPF may be relevant, with ready-meals containing meat, poultry and seafood showing higher associations with mortality risk. All this shows is that more quality research is needed.

Which UPFs are definitely bad for our health?

There is plenty of evidence that shows eating too much fat, sugar and salt leads to poor health, so UPFs that are high in these can be expected to have the same effect. A recent study in the UK confirmed that many, but not all, UPFs carry red traffic light coding and fewer green lights on front of pack labelling.

Other UPFs that are best avoided or minimised are those that undergo extensive formulation. These typically include additives and ingredients you wouldn’t find in your own kitchen (such as emulsifiers, preservatives, synthetic colours and flavours). These foods are designed to be convenient, have a long shelf life, are hyper-palatable and affordable. They tend to be high in calories, lack protein, fibre, vitamins and minerals and tend to displace healthier whole foods in our diets. Examples include energy drinks and fizzy drinks, reformulated potato snacks, powdered soups and instant foods, like noodles.

Of course, the overall balance of your diet is the most important factor, and – even if there’s the odd UPF – a focus on healthy foods should outweigh the risk.

Which UPFs, when eaten in moderation, can form part of a balanced diet?

Although categorised as UPFs, there are some foods that may have some health benefit, justifying their place as part of a balanced diet. Jars of pasta sauce and certain breakfast cereals, provided they’re high fibre and low sugar, are worth checking out – see if you can find brands with minimal additives. Foods like baked beans, hummus and wholegrain breads are often victimised as being UPF, yet these staples play an important role in a balanced diet.

For some people, certain UPFs make it easier and more convenient to eat healthily because they are time-saving and you can still include fresh ingredients, like fruit and vegetables. One study suggests that a diet high in UPFs could still provide most macro- and micronutrients.

Are any UPFs beneficial to health?

It’s important to remember that processing foods is not detrimental. Some processes (such as pasteurisation and fermentation) can improve the safety of food and enhance its nutritional quality.

Some processed foods, including fortified plant-based milks and low-sugar breakfast cereals, as well as gluten-free products make a valid contribution to a balanced, varied diet, and especially so for those on a restricted diet.

In a cost-of-living crisis, these foods may also help manage food costs as illustrated by a 2019 study, this study reported a 43% higher cost for meals composed of unprocessed components.

How can I navigate the food aisles?

The science around food isn’t black and white. This is certainly the case when it comes to UPFs, where it’s tricky for experts to even agree on what defines them.

Potential benefits of UPFs are ease and speed of preparing meals and a reduction in food waste due to longer shelf life. That said, the foods most beneficial to health are those that are whole and minimally processed including fruit and vegetables. While these should make up the majority of our diet, processed foods and some UPFs can be of value, too. Infant and baby formula, products that meet a medical need (such as gluten-free), and fortified foods that give a nutritional boost to those following restricted diets are all UPFs but clearly provide health benefits.

Without question, many UPFs are problematic. They are high in ingredients we should limit, and low in those that provide valuable nutrition. But it is important to remember that, just because a food is industrially produced, this alone does not class it as a UPF, or even make it an unhealthy option. For now, the evidence is still coming in (and there’s little consensus on what constitutes a UPF), so we need to consider the “healthiness” of a food not by the number of ingredients it contains, the number of processes it has been subjected to or whether it has been made in a domestic kitchen, but on its overall merits to us, particularly its nutritional contribution to our diet as a whole.

The best way to do this is by understanding food labels, cooking from scratch when possible, and focusing on a balanced and varied diet.

What's the truth about UPFs? A nutritionist evaluates

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