Ultra processed food

Ultra processed food

Written by Dr Oliver Rabie

Ultra-processed foods (UPFs) have been receiving increased media attention due to the potential health risks associated with eating them. In the UK and USA, UPFs now account for 60% of the average diet, with many children relying on them for most of their daily calorie intake. The UK is the leading consumer of UPFs in Europe.

Health impacts of UPF consumption

UPFs have been linked to an increased risk of:

• Obesity
• Type-2 diabetes
• Cardiovascular diseases
• Irritable bowel syndrome
• Depression
• Frailty conditions
• Certain cancers, including breast, colorectal, gastrointestinal cancers 
• High mortality rates overall

Food processing can also create potentially harmful compounds, such as industrial trans fatty acids and acrylamide which are known to increase the risk of heart disease and some cancers.  Additives like sweeteners, preservatives, and emulsifiers can also negatively impact health; several studies have suggested harmful effects on up to 330 additives currently approved for use in Europe. These include microbiome dysbiosis (an imbalance of  the good and bad bacteria in your gut)  inflammation, and even damage to DNA.

What are Ultra-Processed Foods?

The scientific definition describes UPFs as “Formulations of ingredients, mostly of exclusive industrial use, made by a series of industrial processes, many requiring sophisticated equipment and technology’, which is hard to translate into everyday life! A simpler way of thinking about UPFs is products which are created by industrial processes using ingredients you wouldn’t usually find in your kitchen. Some examples of these ingredients are emulsifiers, stabilisers and flavourings.

Food Classification Systems

One of the most commonly used systems to classify different types of food is the NOVA classification system, although several countries are now developing their own tools as the NOVA classification is considered to have some limitations. 

The tool divides foods into four groups according to their level of processing, and was first developed as an epidemiological tool by the Brazilian physician Carlos Monteiro in Brazil. Foods are classified into the following categories:

• Unprocessed or minimally processed foods such as fruit, vegetables, milk, fish, pulses, eggs, nuts and seeds 
• Processed ingredients such as salt, sugar, butter, lard, oils, vinegar 
• Processed foods, such as  homemade jam, pickles, tinned fruit and vegetables, homemade breads and cheeses. 
• Ultra-processed foods: Ready meals, Processed meats (sausages, chorizo) Sweetened breakfast cereals Biscuits, cakes sweets, sugary 

Why are UPF’s so addictive? 

Another impact of food processing is its change to the food matrix. The components of UPFs are often broken down and reformed into a new product, this makes them more palatable and gives them a ‘melt in the mouth feeling’. This can impact:

• How full you feel after eating them
• How quickly the food transits through your digestive tract
• How easily you digest the food
• How quickly nutrients within the food are absorbed (this is often prior to the food reaching the large intestine and therefore little is available to support your gut microbiome).

Often, UPFs are calorie dense and high in added fat and refined carbohydrates. Evolutionary changes to our brain mean that these foods activate reward/motivation systems, including the endogenous opioid and mesolimbic dopamine pathways. Therefore, when you eat UPF’s your body sees it as a reward and you seek more of them. 

Are all UPF’s bad for us?

Research into ultra-processed foods (UPFs) is ongoing, and we’re still learning about their effects. Some UPFs can have benefits—for example, certain products are fortified with important nutrients like Vitamin D or B12. Others, like baked beans, can be part of a balanced diet.

A recent study on UPFs and Type 2 Diabetes found that while ready meals and processed animal-based products increased the risk, some ultra-processed breads and cereals were actually linked to a lower risk.

Conclusion:

While UPFs are not universally harmful, their high consumption is associated with several health risks, including obesity and chronic diseases. The focus should be on moderating UPF intake and improving overall diet quality by incorporating more whole and minimally processed foods.
 Please see our other helpful blog posts on general tips for healthy eating, the importance of fibre and how to choose healthy protein options. 

References:

1. Rauber, F. et al. (2018) Ultra-Processed Food Consumption and Chronic Non-Communicable DiseasesRelated Dietary Nutrient Profile in the UK (2008–2014), Nutrients, 10(5), pp. 587. doi:10.3390/nu10050587.
2. https://www.bmj.com/content/383/bmj-2023-075294
3. Elizabeth, L., Machado, P., Zinöcker, M., Baker, P., & Lawrence, M. (2020). Ultra-Processed Foods and Health Outcomes: A Narrative Review. Nutrients, 12. https://doi.org/10.3390/nu12071955.
4. https://www.bmj.com/content/384/bmj-2023-077310
5. https://www.researchgate.net/publication/355481122_Ultra-processed_Foods_Weight_Gain_and_Co-morbidity_Risk
6. Fardet A. Minimally processed foods are more satiating and less hyperglycemic than ultra-processed foods: a preliminary study with 98 ready-to-eat foods. Food Funct2016;7:2338-46. doi:10.1039/C6FO00107F. pmid:27125637
7. https://diabetesjournals.org/care/article/46/7/1335/148548/Ultra-Processed-Food-Consumption-and-Risk-of-Type