Ultra-processed foods and IBD

Ultra-processed foods have been linked to poor overall health, increased risk of disease, IBD onset and potentially higher risk of flares in IBD (1,2,3). Despite this, research in both the UK and US suggests that over half of the energy we consume each day comes from ultra-processed foods (1,4). They are often high fat, sugar and salt, and low in fibre and important micronutrients.


What is processed food?

Food processing involves physical, biological and chemical processes that occur after foods are separated from nature, and before they are consumed or used in the preparation of dishes and meals. There are varying amounts of processing from unprocessed or minimally processed to ultra-processed. The term ‘processed food’ has accumulated negative connotations but not all processed foods have a negative impact on our health. Far from it, there are some processed foods that have health benefits (e.g. live yoghurt) and make cooking easier for us (e.g. ready cooked grains or legumes). It’s the amount a food is processed and added ingredients that we wouldn’t use in home cooking that we need to be aware of.


How do we know how processed a food is?

Luckily, to make it easier for us consumers and for researchers, there is an internationally recognised classification system called NOVA. The NOVA classification groups foods according to the extent and purpose of the processing they undergo. (5). This can help us identify foods we should be aiming to consume less of and helpful alternatives that are less processed.

NOVA classifies foods into 4 groups: unprocessed or minimally processed foods, processed culinary ingredients, processed foods and ultra-processed foods.

Lets take a look at these groups in more detail:

Group 1: unprocessed or minimally processed foods

What are they?

Unprocessed (or natural) foods are edible parts of plants (seeds, fruits, leaves, stems, roots) or of animals (muscle, offal, eggs, milk), and also fungi, algae and water, after separation from nature.

Minimally processed foods are natural foods altered by processes such as removal of inedible or unwanted parts, drying, crushing, grinding, fractioning, filtering, roasting, boiling, pasteurisation, refrigeration, freezing, placing in containers, vacuum packaging, or non-alcoholic fermentation. None of these processes adds substances such as salt, sugar, oils or fats to the original food.

Examples of unprocessed or minimally processed foods

Fresh, squeezed, chilled, frozen, or dried fruits and leafy and root vegetables, grains, legumes, meat, poultry, fish and seafood, eggs, milk, fresh or pasteurised fruit or vegetable juices without added sugar, sweeteners or flavours, grits, flakes or flour made from corn, wheat, oats, or cassava, pasta, couscous and polenta made with flours, flakes or grits and water, tree and ground nuts and other oil seeds without added salt or sugar, herbs and spices, plain yoghurt with no added sugar or artificial sweeteners added; tea, coffee, drinking water.

This group also includes foods made up from two or more items in this group, such as dried mixed fruits, granola made from cereals, nuts and dried fruits with no added sugar, honey or oil; and foods with vitamins and minerals added generally to replace nutrients lost during processing, such as wheat or corn flour fortified with iron or folic acid.



Group 2: Processed Culinary Ingredients

What are they?

Ingredients such as oils, butter, sugar and salt, are substances derived from Group 1 foods or from nature by processes that include pressing, refining, grinding, milling and drying. The purpose of such processes is to make durable products that are suitable for use in home and restaurant kitchens to prepare, season and cook Group 1 foods and to make with them varied and enjoyable hand-made dishes and meals, such as stews, soups and broths, salads, breads, preserves, drinks and desserts.

Examples of Processed Culinary Ingredients

Salt mined or from seawater; sugar and molasses obtained from cane or beet; honey extracted from combs and syrup from maple trees; vegetable oils crushed from olives or seeds; butter and lard obtained from milk and pork; and starches extracted from corn and other plants.

 

Group 3: Processed Foods

What are they?

Processed foods are made by adding salt, oil, sugar or other substances from Group 2 to Group 1 foods. Processes include various preservation or cooking methods, and, in the case of breads and cheese, non-alcoholic fermentation. Most processed foods have two or three ingredients, and are recognizable as modified versions of Group 1 foods. They are edible by themselves or, more usually, in combination with other foods. The purpose of processing here is to increase the durability of Group 1 foods, or to modify or enhance their sensory qualities.

Examples of Processed Foods

Bottled or canned vegetables, canned fish, fruits in syrup, cheeses and freshly made breads.

 

Group 4: Ultra-processed food and drink products

What are they?

Ultra-processed foods usually contain ingredients that you wouldn’t add when cooking homemade food. We may not recognise the names of these ingredients as many will be chemicals, colourings, sweeteners and preservatives. Ingredients of these formulations usually include those also used in processed foods, such as sugars, oils, fats or salt. But ultra-processed products also include other sources of energy and nutrients not normally used in culinary preparations. Some of these are directly extracted from foods, such as casein, lactose, whey and gluten. Many are derived from further processing of food constituents, such as hydrogenated or interesterified oils, hydrolysed proteins, soya protein isolate, maltodextrin, invert sugar and high-fructose corn syrup. Additives in ultra-processed foods include some also used in processed foods, such as preservatives, antioxidants and stabilizers. Classes of additives found only in ultra-processed products include those used to imitate or enhance the sensory qualities of foods or to disguise unpalatable aspects of the final product. These additives include dyes and other colours, colour stabilizers; flavours, flavour enhancers, non-sugar sweeteners; and processing aids such as carbonating, firming, bulking and anti-bulking, de-foaming, anti-caking and glazing agents, emulsifiers, sequestrants and humectants. A multitude of sequences of processes is used to combine the usually many ingredients and to create the final product (hence ‘ultra-processed’).

The overall purpose of ultra-processing is to create branded, convenient (durable, ready to consume), attractive (hyper-palatable) and highly profitable (low-cost ingredients) food products designed to displace all other food groups. Ultra-processed food products are usually packaged attractively and marketed intensively.

Examples of typical ultra-processed products

Carbonated drinks; sweet or savoury packaged snacks; ice-cream, chocolate, candies (confectionery); mass-produced packaged breads and buns; margarines and spreads; cookies (biscuits), pastries, cakes, and cake mixes; breakfast ‘cereals’, ‘cereal’ and ‘energy’ bars; ‘energy’ drinks; milk drinks, ‘fruit’ yoghurts and ‘fruit’ drinks; cocoa drinks; meat and chicken extracts and ‘instant’ sauces; infant formulas, follow-on milks, other baby products; ‘health’ and ‘slimming’ products such as powdered or ‘fortified’ meal and dish substitutes; and many ready to heat products including pre-prepared pies and pasta and pizza dishes; poultry and fish ‘nuggets’ and ‘sticks’, sausages, burgers, hot dogs, and other reconstituted meat products, and powdered and packaged ‘instant’ soups, noodles and desserts.



How can we identify ultra-processed foods?

Sometimes it can be tricky to identify food that has been ultra-processed because the same type of food could be minimally processed, processed or ultra-processed, depending on how it’s been made.

For example:

1.       Bread made from wheat flour, water, salt and yeast is processed, but add emulsifiers or colourings and it becomes ultra-processed.

2.       Plain oats, corn flakes and shredded wheat are minimally processed, but when the manufacturer adds sugar, flavourings or colourings, they become ultra-processed breakfast cereals.

3.       Plain yoghurt is minimally processed, but add sweeteners, preservatives, stabilisers or colourings and it becomes ultra-processed.



3 things to look out for

  1. A long list of ingredients, especially if it includes ingredients you don’t recognise the names of or wouldn’t use in cooking at home, may indicate that a food is ultra-processed.

  2. High fat, sugar and salt content – look out for the traffic light label on foods for levels of these.

  3. Aggressive marketing and branding.



Take Away Points

  • Food processing involves physical, biological and chemical processes that occur after foods are separated from nature, and before they are consumed or used in the preparation of dishes and meals.

  • Many foods we buy are processed in some way and not all food processing is not bad for our health. Some processing increases safety of foods (e.g. pasteurising milk), makes new food products (e.g. yoghurt and bread), and helps us save time in the kitchen (e.g. ready cooked canned legumes)

  • However, a high intake of ultra processed foods has been linked to poor health, increased risk of disease, IBD onset and possibly more frequent flares so these are the foods we should aim to reduce reliance on.

  • Some ultra-processed foods contain ingredients like carrageenan and carboymethylcellulose that recent research has shown may have a negative impact on gut health and IBD.

  • It is difficult to exclude all ultra-processed foods and there is no need to exclude them completely as some can be tasty, convenient and still form part of a balanced diet but we can make simple swaps to help reduce our intake of these foods to help improve our health on a daily basis. For example, opting for freshly made bread rather than industrially produced, plain yoghurt rather than sweetened and just add our own fruit, whole fruit and nuts (or nut butter) rather than highly processed cereal or snack bars.


If you would like help and support with your IBD and what dietary and lifestyle changes would be appropriate for you, please get in touch. You can book a free call, where I can get to know you, your journey, your struggles, your life, and we can chat about the best route forward for you. You can also ask any questions you have about working with me.

I have also written a free e-book to help you find a way forward for your everyday life with Inflammatory Bowel Disease. Whether you are right at the beginning of your journey with IBD or have been living with your condition for years and feel like you have tried almost everything, there are things you can do everyday, beyond the medication you are taking, to help you take back control.

References

  1. Rauber, F., da Costa Louzada, M. L., Steele, E. M., Millett, C., Monteiro, C. A., & Levy, R. B. (2018). Ultra-Processed Food Consumption and Chronic Non-Communicable Diseases-Related Dietary Nutrient Profile in the UK (2008⁻2014). Nutrients, 10(5), 587. https://doi.org/10.3390/nu10050587

  2. Narula N, Wong E C L, Dehghan M, Mente A, Rangarajan S, Lanas F et al. Association of ultra-processed food intake with risk of inflammatory bowel disease: prospective cohort study BMJ 2021; 374 :n1554 doi:10.1136/bmj.n1554

  3. Levine, A., Rhodes, J. M., Lindsay, J. O., Abreu, M. T., Kamm, M. A., Gibson, P. R., … Lewis, J. D. (2020). Dietary Guidance for Patients with Inflammatory Bowel Disease from the International Organization for the Study of Inflammatory Bowel Disease. Clinical Gastroenterology and Hepatology. doi:10.1016/j.cgh.2020.01.046 

  4. Juul F, Parekh N, Martinez-Steele E, Monteiro CA, Chang VW. Ultra-processed food consumption among US adults from 2001 to 2018. Am J Clin Nutr. 2022 Jan 11;115(1):211-221. doi: 10.1093/ajcn/nqab305. PMID: 34647997.

  5. Monteiro, C., Cannon, G., Moubarac, J., Levy, R., Louzada, M., & Jaime, P. (2018). The UN Decade of Nutrition, the NOVA food classification and the trouble with ultra-processing. Public Health Nutrition, 21(1), 5-17. doi:10.1017/S1368980017000234

Clemmie Macpherson