What is leaky gut syndrome?
Leaky gut, which is also known as increased intestinal permeability,1 is when the lining of our gut is more porous than normal. When this happens, it allows particles like undigested food or pathogenic bacteria into the bloodstream. This results in the immune system being alerted, which in turn can cause a cascade of inflammation and other immune reactions.2
But what causes leaky gut? There are a number of factors that can contribute to it, some of which are unavoidable, like certain kinds of medication.3 But some are avoidable, such as stress levels, poor sleep, consuming a diet high in processed foods and low in nutrient-dense foods, and consuming foods that you’re intolerant to.4, 5, 6
Symptoms of leaky gut
As leaky gut can affect the entire body, the symptoms can be varied, but here are some of the most common:7
Food intolerances or allergies
Aches and pains
These symptoms can be a nuisance to our everyday lives. But, there are ways to try and alleviate them — beginning with your diet and lifestyle.
What is an autoimmune diet?
Starting with your diet, there is one type that can help: autoimmune diets. These are designed to help relieve the symptoms of autoimmune conditions, and the most popular of which is the Autoimmune Protocol (AIP), or Autoimmune Paleo diet. This diet follows the principles of a paleo diet but goes further to remove many of the foods that can trigger autoimmune responses or intolerances. Its ultimate goal is to maximise nutrition, and minimise trigger foods, for the immune system and gut.8
There’s an extensive list of foods that are excluded from AIP, but here are the most important:
- Grains, including wheat, rice, oats, corn, and millet
Pseudograins, including chia, quinoa, buckwheat, and amaranth
All dairy products
Nuts and seeds, including butters, flours, oils, coffee, and cocoa
All nightshades, including potatoes, tomatoes, eggplants, peppers, cayenne, and paprika
Sweeteners, both natural, and artificial
Refined and processed foods
Food additives, such as emulsifiers and thickeners
- With this in mind, what can you eat on AIP? Typically, your meals would consist of the following:9
Meat and organ meats (ideally grass-fed)
Fish and shellfish
Herbs and spices
Oils, such as olive and avocado oil
Vegetables, with the exception of nightshades
How an autoimmune diet can aid gut health
There are a number of ways that this approach can support your digestive health and help alleviate leaky gut symptoms.
As one major factor in gut health is inflammation, AIP removes foods that are inflammatory, like processed foods, coffee, and alcohol.10 It also removes the majority of foods that can cause intolerances, as these can cause significant inflammation throughout the digestive tract.11
It’s important to add that many of the eliminated foods can also be problematic for your microbiome — your general gut health. Processed and high-sugar foods can have a rage of impacts on the gut flora, including feeding the bad bacteria that can damage the gut lining, and so AIP could prove beneficial to those who don’t even have leaky gut. 12
However, the benefits of AIP aren’t just about what you remove, but also what remains. Although the foods that are included are rather limited, they are all nutrient-dense. By consuming a lot of vegetables, for instance, you’ll be eating plenty of prebiotic fibres that feed the good bacteria found in the gut.13 The vegetables included are also high in antioxidants, which can help to protect the gut from damage.14
As meat is one of the main food groups, you’ll also be consuming beneficial levels of zinc and glutamine. Zinc and glutamine are both essential nutrients that can protect the gut lining, with zinc in particular also having anti-inflammatory effects throughout the body, and in support of a healthy immune system.15, 16, 17
Fish and seafood are also included in the diet and are good sources of omega-3 fatty acids, with omega-3s also being able to reduce inflammation within the gut and support healthy levels of beneficial bacteria.18 , 19
One last inclusion that can support gut health is fermented foods. These are a natural source of probiotics, or beneficial microorganisms, and their inclusion in your diet can help to protect the gut lining from further damage.20
The pros and cons of an autoimmune diet
As with any diet, an autoimmune diet can offer many benefits, but there are also downsides to consider.
One positive is that AIP is not designed to be followed forever. It’s most commonly used as a tool to flood the body with nutrition and restore gut and immune health. After following it for a period of time many people are able to reintroduce a variety of foods without triggering symptoms.
AIP is also incredibly nutritious. As, on the diet, you’re encouraged to eat high-quality proteins and vegetables, you’ll be consuming a variety of vitamins, minerals, amino acids, antioxidants, and fatty acids. And more so, the exclusion of grains, legumes, and coffee means that those foods are unable to bind to nutrients and prevent absorption into the body.21
Yet, the diet is somewhat restrictive. Going out to eat socially or eating at a friend’s place can become complicated when your diet is so restrictive. There are also limited options for when you need a quick meal, so it’s often encouraged that you cook your meals in batches and freeze the leftovers, which can take time and effort that you might not have.
Although the AIP diet doesn’t last forever, the reintroduction period can take a long time. Each food is reintroduced one at a time, and you need to monitor yourself for symptoms for 5-7 days. Only after you’re symptom-free for a week can you incorporate the food into your everyday diet.22
Another consideration is that an AIP diet is nearly impossible to do as a vegetarian or vegan. This is because foods such as eggs, nuts, seeds, beans, and grains are all excluded, and meats and fish are encouraged. If you follow a plant-based diet, then this might not be the right approach for you. Finally, AIP is only one piece of the puzzle in gut health. Other factors, such as sleep and stress, play roles in how your gut functions, and so it’s important to get a grip on these in addition to your diet.
The bottom line: keeping your gut healthy
Ultimately, the foundation of a healthy body is a balanced diet and lifestyle. This applies to those with leaky gut, too. Make sure you exercise regularly, reduce your alcohol intake, and follow a gut-friendly diet, like an autoimmune diet. It might also be worth taking a probiotic and prebiotic daily, to keep the amount of good bacteria in your gut beneficial, and to keep them healthy and fed.
If you'd like to read more about the benefits of keeping a healthy gut, as well as find more information on how you can promote good gut health, then head over to our Gut Health advice centre.
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3Arrieta, M. C., Bistritz, L., and Meddings, J. B. (2006). Alterations in intestinal permeability - Gut, 55(10)
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7McMillen, M. (2013). Leaky Gut Syndrome: What Is It? - WebMD
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9Ballantyne, S. (2018). The Autoimmune Protocol - The Paleo Mom
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22Ballantyne, S. (2018). The Autoimmune Protocol - The Paleo Mom