Is there an inflammatory bowel disease diet that helps achieve remission? Anecdotally speaking, numerous people on the interwebz and social media believe so.
But the interesting thing about this is that there really isn’t a single diet. Some people do great with a whole food plant-based(WFPB) diet. Others do well with Carnivore or Keto.
So what gives? Why do these seemingly disparate diets both seem to work? It may not be so much what they have in them, than what they don’t.
A recent review on the effects of food additives on the gut may give us some clues.
The gut in IBD vs healthy people
Clearly, inflammation is a primary issue in people with IBD compared to healthy controls. But what drives the increased inflammation in people with IBD?
There are a few differences going on in the gut of people with IBD. Firstly, there is a marked dysbiosis of the microbiome. There’s a reduction in beneficial microbes such as Faecalbacterium prausnitzii and an increase in pathogens such as Campylobacter jejuni.
Secondly, people with IBD have increased intestinal permeability compared to healthy people. Furthermore, there are abnormalities in the mucus layer of people with IBD.
Finally, people with IBD have altered levels of short chain fatty acids(SCFAs). The 3 primary SCFAs in the gut are acetate, propionate, and butyrate. These SCFAs have various roles in optimizing gut health, particularly decreasing inflammation.
They also regulate systemic physiology by impacting blood glucose regulation, metabolism, and many other organs systems.
What are food additives?
Food companies add food additives to alter the quality or physical structure of food. Some additives are beneficial, such as probiotics or prebiotics.
But generally speaking, food companies include these additives specifically to promote health. Other food additives alter other characteristics such as taste, texture, and appearance. Some of these additives may have detrimental effects on gut health.
Artificial sweeteners increase the sweetness of a food while contributing less to caloric load. Common sweeteners include sucralose, aspartame, and others.
Emulsifiers alter the texture of a food, improve mixing, and extend shelf-life. Common emulsifiers include polysorbate 80, carboxymethylcellulose(CMC), carrageenan, and more.
As the name suggests, food colorants change the appearance of food. In many instances, processing creates unpleasant colors in food. Food companies use food colorants to make processed foods more appealing to consumers.
Regulators recently removed the food colorant titanium dioxide due to potential health concerns.
There are also other types of additives that may impact gut health. Food companies use food preservatives to extend shelf-life. However, extending shelf-life means using antimicrobials which may impact healthy microbes.
Other additives such as thickeners and stabilizers are also common additions to processed foods.
Mechanisms of injury
So how do food additives negatively impact gut health?
Firstly, data in animals models and some human data shows that food additives cause dysbiosis. As a result, this causes a cascading effect that alters other abnormalities common in IBD.
Secondly, animal models show that food additives may decrease mucus production, increase intestinal permeability, and alter SCFA production. If these sound familiar, it’s because they are common problems in people with IBD.
This review paper does an excellent job of presenting the data on how each type of food additive negatively impacts the gut. You should definitely check it out.
A graphical representation is also in the paper:
Parsing through the data seems to implicate food additives as things to restrict in an inflammatory bowel disease diet. But it’s important to point out that the vast majority of data is in rodents.
Is there evidence that they may be a problem in humans as well?
Evidence for the exclusion of processed foods in an inflammatory bowel disease diet
Relying on rodent data to show the mechanisms behind why something happens is foolish unless there is human outcome data to support it. We need to know it is an issue for us before we go searching for why it happens.
At the very least, there is a correlation between consumption of processed food and IBD. The incidence of IBD in people who eat 5 or more servings of ultra-processed foods per day is 82% higher than those who consume less than 1. It’s 67% higher in those eating 1-4 servings per day.
This is an important consideration, because food additives are only added to processed foods. This may also explain why people who go Carnivore, Keto, or WFPB see improvements in IBD. It’s not what they’re eating, it’s what they’re not eating.
This doesn’t mean, in and of itself, that processed foods are bad for everyone. It may be that, in those susceptible to IBD or with it, that processed foods tip them over the edge.
Furthermore, it also doesn’t mean that it’s the food additives per se that are the problem. Processed foods also tend to be higher calorie, higher fat, and higher sugar. All of these factors also may play a role in IBD.
Food additives may be something you want to remove from an inflammatory bowel disease diet. Data in humans show that processed foods increase the risk of IBD. In addition, animal models show that food additives promote mechanisms that drive IBD.
But this doesn’t mean that food additives are necessarily the problem. Other factors within processed foods may be the drivers, such as high calorie load and the high fat/high sugar combo.
This is an important consideration. Essentially, it means that rather than eliminating food additives, it’s processed foods in general that one should avoid.
As a result of the data on food additives, many processed food companies attempt to make processed foods without additives or more natural versions. This may not do the trick.
This may be why a recent paper showed the autoimmune protocol to be effective for managing IBD. AIP, along with the other diets mentioned above, eliminate processed foods for at least a period of time. We chat about that in a video we did here.
Therefore, rather than focus on limiting food additives, focus on eliminating processed foods for the management of IBD.