A hot topic that's been buzzing in the nutrition world is Ultra-Processed Foods (UPFs). No doubt, you’ve probably heard of it, but what does it really mean? How do they impact our health and how do we know if a food is ultra-processed?
The NOVA Classification for Ultra-Processed Foods
The NOVA classification is a groundbreaking system that categorises foods based on their processing levels. Here's a quick rundown with a list of ultra-processed food examples:
Unprocessed or Minimally Processed Foods:
These are foods in their natural state or those that have undergone minimal processing that doesn't substantially alter their nutritional properties. The processing is mainly to preserve the food's natural characteristics. E.g. Fresh fruits (like apples, which are picked from trees and consumed in their natural state) and vegetables (like carrots, which might be washed and peeled), grains (like rice, which is hulled), meat (which might be simply cut and refrigerated), milk (which could be pasteurised to eliminate bacteria), and eggs.
Processed Culinary Ingredients:
These are ingredients derived from the first group (unprocessed or minimally processed foods) and are used to season and cook. They help in making diverse and palatable homemade dishes from the first group. E.g. Sugar (obtained by refining sugarcane), oils (like olive oil, extracted from olives), butter (churned from cream), and salt (mined or extracted from seawater).
Processed Foods: These are made by adding salt, sugar, or other substances from the second group (processed culinary ingredients) to foods from the first group. They are still recognisable as their original plant or animal source but have been preserved or enhanced in flavour. E.g. Canned vegetables with added salt (like green beans preserved in brine), fruits in syrup (like peaches sweetened and preserved in a sugary liquid), cheeses (where milk is fermented and sometimes salted), and freshly made bread (combining grains with ingredients like salt and yeast).
Ultra-Processed Foods: These are industrial formulations made predominantly or entirely from substances derived from foods and additives. They are typically created to be durable, palatable, and convenient, but often at the expense of nutrition. They often mimic the appearance and sensory qualities of natural foods. E.g. Soft drinks (which combine water, sugar, flavourings, and possibly colourants), packaged snacks (like crisps, which might use potato flakes instead of whole potatoes and contain various flavour enhancers and preservatives), reconstituted meat products (like chicken nuggets, which are often a mix of meat, fillers, and additives), and pre-prepared frozen dishes (like a microwaveable meal, which might contain preservatives, colourants, and flavour enhancers).
One way of distinguishing a UPF is if it contains ingredients that you wouldn’t have in your own kitchen, then it’s probably a UPF. We’d normally cook with food and ingredients in groups one to three.
Once You Pop You Can't Stop
Ultra-processed foods are typically highly palatable, energy-dense and come with a long shelf life. Ever wondered why that pack of crisps tastes so good and lasts so long? Well, it's not magic, it's science and a lot of engineering. These foods are tested and optimised to increase sales and profit margins for companies year over year!
The Health Impact of Ultra-Processed Foods
While UPFs might be convenient and tasty, there's a flip side. Here are some concerns raised by various studies on the health impact of ultra-processed foods:
Colourants: Linked to hyperactivity in children. The exact mechanism isn't fully understood, but it's believed that these additives might affect neurotransmitter function, leading to increased activity levels.
Emulsifiers: Can disrupt our gut health by altering the composition of our gut microbiota, potentially leading to inflammation and digestive issues.
Endocrine and metabolic issues: UPFs can interfere with our hormones, leading to problems like insulin resistance, weight gain and obesity.
Cardiovascular problems: Beyond the high salt and high fat content, the highly degraded physical structure, gut and metabolic changing nature of UPFs may contribute to high blood pressure and heart disease.
Mental health issues: Higher UPF consumption is linked with higher chances of adverse mental health, such as depression and anxiety.
Cognitive health: UPFs may reduce the size of the hippocampus, a critical region for memory and learning. Given the established gut-brain axis, poor gut health from UPFs can also impact brain health and, by extension, overall well-being.
It’s important to note, that the research is coming in fast, but is still young. Some randomised controlled trials are based on very small samples, or larger studies are observational and conclude associations, not causations. Like most studies, they isolate, so for example studies have found a handful of emulsifiers to be linked to gut issues, but there are hundreds of different emulsifiers that are currently used in our food system. So does that mean all emulsifiers are bad? Well, we don’t know, but based on these findings, caution is wise. Furthermore, we know that a diet high in UPFs is associated with all-cause mortality.
The Paradox of "Healthy" Ultra-Processed Foods
Many UPFs, even those marketed as "health foods", boast about their isolated nutrients. "Rich in Omega-3!" or "Packed with Vitamin C!" sounds beneficial, right? But let's pause and reflect. A whole food, like an orange or a walnut, comes with thousands of phytochemicals working in harmony. When we focus solely on the presence of certain nutrients in UPFs, we might overlook the absence of countless others. If whole foods came with a food nutrition label, it would have hundreds or thousands of ingredients!
A common sentiment I've heard is that if you can't understand the ingredients on a UPF label, it's best avoided. While this can be a helpful guideline for some, I believe it's an oversimplification. For instance, "ascorbic acid" might sound unfamiliar to many, but it's just vitamin C. Similarly, "tocopherol" is vitamin E. Let's be cautious not to fall into the trap of scaremongering and instead educate ourselves about what these terms truly mean.
It's worth noting that UPFs aren't just the obvious junk foods. Many of us consume them unknowingly. Take supermarket bread, for instance. They're often full of preservatives and emulsifiers, engineered for that soft, fluffy texture and extended shelf life. True bread, in its simplest form, contains just flour, yeast, and water, with maybe a pinch of salt and oil. Even the fresh bakery sections in some supermarkets, like Morrisons, can be a minefield of emulsifiers.
Flavoured yoghurt is another culprit. Often packed with colourants, emulsifiers, and flavourings. Instead, opt for plain, Greek, or natural yoghurts and jazz them up with fresh fruit and a drizzle of honey.
And let's talk about plant milks. Many mass-produced versions (like Alpro and Oatly) are brimming with additives like seed oils, emulsifiers, flavourings, and stabilisers. Those "barista" versions? They often contain even more oils to enhance their coffee compatibility. A high-quality soya milk for example should be simple: spring water, soya bean, and perhaps a touch of salt. Always check the label and aim for those with minimal ingredients.
Let's Be Real
It’s really important that we acknowledge that not everyone has easy access to fresh produce. In many areas, UPFs might be more accessible and affordable than fresh fruits and veggies. So, how do we navigate this? It's about balance and making the best choices within our means. Opt for UPFs with fewer additives and more whole ingredients. And remember, not all UPFs are void of nutrition. Some can be part of a balanced diet when consumed in moderation.
While UPFs have a place in our modern world, it's crucial to approach them with knowledge and mindfulness. Let's celebrate whole foods, appreciate the convenience of UPFs when needed, and always strive for balance.
UPFs and health status
UPFs on the microbiota-gut-brain axis
Additives & emulsifiers
UPFs and cognitive decline
UPFs and disease