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What Are UPFs?

UPF stands for Ultra-Processed Foods.  These are foods that you probably eat on a daily basis without thinking about it – in some cases the packaging and media may even have convinced you that they are a “healthy” option!

Ultra-Processed Foods are foods (or edible formulations) that contain ingredients produced via extraction or chemical modification – ingredients that you would not find in a home kitchen.  They include “plant based” products, bread, pizza, ice-cream, fizzy drinks and many other packaged foods.

My post How to Reduce Ultra-Processed Foods (UPFs) in Your Diet, explains more about the different food processing classifications with examples of each.

Why Do We Have UPFs?

Some of the main reasons why these foods were produced and have become ‘normal’ to us include:

  • Convenience – quick to prepare, or readily available when out of the house
  • Low cost
  • Quick to eat
  • Can be easily mass produced
  • Appealing taste (see later)

Why Do UPFs Have A Bad Reputation?

Associations with poor health in scientific studies

The foods are produced by scientists, and their effects on health are being studied by scientists. The first group of scientists will be looking to persuade us to buy more of those foods, while the second group appear to be finding out why we shouldn’t.  Who funded a study and the researchers’ conflicts of interest are always worth checking.

It has been stated that UPFs are linked to many, many health conditions.  But, this is a relatively new area of study meaning that the number of reliable and long-term studies available is limited.  Many of the studies have been small or include unreliable and/or non-specific data collection methods.  The results between some studies are also conflicting.  When we see reports about “the latest study” it is important to look beyond the headlines.

The term “associated with” should be used with caution.  It does not necessarily indicate cause and effect.   For example, “there is a high association between UPF consumption and poor mental health” could mean that people with mental health problems are more likely to choose UPFs; or that people have mental health problems because they choose UPFs.  Knowing more about which came first; the health of participants who did not eat UPFs, and the participants’ health and lifestyles would help to give a better understanding.

However, this does not mean that all studies are bad.  Nor can we dismiss all of the outcomes.  Observational studies (those looking at changes in a population over time) can highlight issues that need further research.  For example, a 19 year study in France (Schnabel, et al) included 44,551 participants and found that UPFs were associated with a higher risk of all-cause mortality (602 participants died during the course of the study and were analysed).  Two large studies in Spain, also found that there was an increased risk of all-cause mortality amongst those consuming the largest amounts of UPFs.  Combined, these studies appear to have significant outcomes.

There are also some large studies showing increased risks of IBS and depression amongst individuals with higher UPF consumption.

The term UPF is of course very wide ranging.  Could problems with UPFs be down to the type of UPF?  Could it be particular formulations that present the issue?

What is missing from UPFs?

We have long known that a diet rich in whole foods, such as the Mediterranean Diet, is best for our health.  Eating in this way gives us high levels of nutrients that support our body, with less of the things that don’t.  When we eat a UPF, we are not eating a whole food and, therefore, we are missing those nutrients.

When a food is highly processed, much of those beneficial nutrients are removed or destroyed.  This means that there is little, if anything, naturally supportive to the body.  Without those nutrients the body cannot function effectively.

Some of the UPFs, such as breakfast cereals, are fortified.  This means they have nutrients added into them.  These then become the marketing tool – “buy this food because it has added vitamins!”  One big difference here is that the food is only fortified with selected nutrients – does that make up for all the nutrients that would be contained in a whole food?  It is unlikely.

In many cases, the fortification of food is a legal requirement.  In the UK and other countries, all white flour must have calcium, iron, vitamin B1 and vitamin B3 added to it.  Folic acid (the synthetic form of folate) will also be added over the next couple of years following changes to the law.  This fortification is to make up for the nutrients lost as a result of the removal of the bran and wheat germ.  Therefore, if you look at the ingredients list you will notice that a product made from white flour has these nutrients added but not a product made from wholewheat (unless the producer has chosen to add them voluntarily).  This applies to organic flour as well as non-organic.

What is added?

One notable issue with UPFs is the inclusion of ingredients that we know contribute to poor health outcomes.  For example, they may contain large amounts of salt or sugar, or they may include sources of trans fats.  The study in France that I referred to above, highlighted that “higher ultraprocessed [sic] foods consumption was associated with a lower adherence rate to nutritional recommendations”.  The results showed higher intakes of saturated fat and sugar, as well as lower intakes of fibre and protein, in those with greater UPF intake.

There is also a large amount of uncertainly around the safety of artificial ingredients, including sweeteners and emulsifiers.  I don’t want to detail specifics here because it is a highly controversial area.  Officials state that the ingredients have been shown to be safe.  However, it is worth bearing in mind that:

  • The safety tests for these items tend to be completed on single chemicals. These means that there is no testing for items where they are used in combination.  We do not therefore know if they remain safe when used together.
  • The amount of the item tested varies. There is a popular statement that gets reported in relation to such testing that the item was deemed safe at the quantities people are expected to consume the item in.  How many people exceed those amounts as they consume the artificial ingredient in multiple foods and drinks throughout each day?

There are some studies that suggest that the addition of artificial sweeteners increases the absorption of glucose within the gut.  They are also thought to disturb the balance of the microbiome, which can have a negative impact on the general heath of affected individuals.

Emulsifiers are also believed to have a negative impact on the gut microbiome with two types being associated with cardiovascular disease (Sellem, et al. 2023).

But They Taste So Good!

That is entirely down to the R&D departments.  Research tells the food developers what balance of fat, salt and sugar works well for different products in order for customers to ‘enjoy’ the food and to manipulate them into buying more.  Studies have shown the effects different tastes have on the brain – even to the extent that they trigger a dopamine effect.  The foods become associated with pleasure.  There is even evidence to suggest that the formulations used in UPFs “have a supra-addictive effect on brain reward systems” (Gearhardt, et al.  2023)!  It is suggested that it isn’t just the balance of carbs and fats however, but how quickly they pass through the gut to produce the feelings of reward that adds to the effect.  In balance, this could also be said of many home recipes that include sugar and fat (butter) too.

Furthermore, additives are included in UPFs to influence the taste and texture of the product so that consumers can enjoy them.  Without these additives, the product may well be unappealing!

References/Further Reading