Fast and furious: what does 'processed food' mean for our gut?

5 Minute Read
down view of Blueberry covered white chocolate and Vanilla cheesecake laid on a marble effect kitchen counter.

Most of us are aware that eating lots of junk food can be detrimental to our health but what does this actually mean for our gut health?

Firstly it is important to differentiate between the terms ‘processed’ and ‘ultra-processed’. The term ‘processed’ in relation to food generally speaking can have some negative connotations when actually many foods are processed to some degree or other. Think about olive oil and butter as two examples. In fact, the term processed basically means modifying a raw food source before eating it. This includes basic processes like cooking, fermenting, grinding, pasteurising, smoking or curing. However there is a marked difference between this type of processing and the kind that uses a whole bunch of added ingredients and chemicals. When we refer to foods that have been heavily manipulated with added sugar, unhealthy fats, refined salt, artificial sweeteners, preservatives and emulsifiers, basically ingredients you might not recognise as foods, we call these ‘ultra-processed foods’ (UPF). The unfortunate thing is that these foods are now readily available and often in unlikely sources to include cookies, fizzy drinks, sauces, fruit juices, condiments, ready meals, confectionary, even ‘healthy’ bars and cereals, the list goes on. In short, they are everywhere.

But what makes them so unhealthy?

Well, when you highly process a food with these type of ingredients you can have a perfect storm of making a food behave very differently since it changes the structure of the food itself. This means it can have a very different and often unfavourable effects on our body. Moreover, and in general, ultra-processed foods are lower in nutritional value and fibre content and often high in refined carbohydrates, sugar and fat. This is why high consumption of them have been linked with many different conditions to include type II diabetes, obesity and even cognitive conditions. It also turns out that they don’t do much for our gut microbes too.

Essentially our gut microbes survive on the food choices that we make and they are dependent on fibre and polyphenols which are pretty much devoid in a lot of ultra-processed foods. Plus it is what is actually in these foods that can also have a detrimental effect on our gut microbiome. Research indicates that artificial and chemical ingredients included in a lot of ultra-processed food can shift the composition of the gut microbiome meaning we have less of the ‘good bugs’ in our gut and more of the less favourable microbes as well as potentially impacting on functioning of the gut barrier. Moreover it can also alter the metabolic activity of our microbiome which can lead to heightened inflammation. This is in contrast to those who consume high amounts of plants and lower ultra-processed foods who seem to have a more healthier gut microbiome profile.

So what do we really need to be looking out for in terms of added ingredients?

Firstly let’s start with one of the most familiar which is added sugar. I think it is fair to say that we are all pretty much aware that we need to mindful around the amount of sugar in our diet since high consumption has been linked to myriad metabolic and other serious health conditions. However, it isn’t sugar that is inherently ‘bad’, it is more the fact that in recent years our intake has skyrocketed with the rise of ultra-processed foods. Plus, sugar can also pop up in foods that we wouldn’t knowingly associate with being sweet. Of course, we would assume that cake has sugar in it but things like many ready-made soups can also be laden with added sugar and that’s why it can become so confusing. However with a wider knowledge around excessive consumption of sugar, many of us may have been hoodwinked into the ‘no-added sugar’ story - the idea that artificially sweetened foods and drinks could satisfy our taste for sugar without the negative consequences. Sound too good to be true? Yup. Studies show that certain artificial sweeteners including sucralose, aspartame and saccharin can have a detrimental effect on our gut microbiome and have also been linked to other metabolic conditions.

Another type of food additive we need to be aware of is emulsifiers which include lecithin, carrageenan, xanthan and guar gums to name a few. Emulsifiers are there to prevent the separation of ingredients within the products as well as acting like thickening agents to improve texture and to extend shelf life. Doesn’t sound so bad but actually when you look a bit deeper at the effects on our microbiome is anything but good.

Studies indicate that certain emulsifiers can alter the composition of the gut microbiome and can even have a damaging impact on the gut barrier which can lead to heightened inflammation in the body. Not all emulsifiers are ‘harmful’ per se and the idea is not to create fear around food but if these form a large part of the diet it is worth considering how these can be reduced or replaced.

And this is really the key point, in looking at the overall quality of our diet and the amount of ultra-processed foods that we are consuming rather than fixating on avoiding them altogether. Being knowledgable about our food and what this means for our health, and our gut, is empowering but being too restrictive is not only unnecessary but can also create more anxiety and stress around our food and eating patterns. Realistically, unless we are cooking everything from scratch, some element of our food will be processed, even ultra-processed, at times which is part of a modern lifestyle. It is more the cumulative effect of many different additives and chemicals along with many other factors that can impact on our gut health. Rather it is about trying to juxtapose these foods in the majority with meals cooked from scratch and a diet that is rich in plant foods which is something that ION* massively advocates. In addition, anything we can also add to help to strengthen the health of our gut and our gut barrier, like adding in a supplement like ION*, will also help us to mitigate some of the side effects. Really no food should be off the menu but thinking food first rather than chemicals in the majority is really the main take-away point.

And…if you want something to hit the sweet spot without the added sugar for both you and your microbiome why not make my Blueberry Swirl Cheesecake here

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