There’s the gluten-free diet, ketogenic diet, vegan diet, Zone diet, South Beach diet, and more. If you listen to the news or are active on social media, you likely have heard of these diets and know people who tried them.

Among people with rheumatoid arthritis (RA), there is a popular notion that RA can be managed with diet, thereby skipping the undesirable side effects associated with certain medication. There is even an autoimmune protocol (AIP) diet which, by its name alone, makes you think you should be on board.

What Is the AIP Diet? The Autoimmune Protocol Diet Explained

In autoimmune diseases, the body mistakenly attacks its own tissues, causing damage. The autoimmune protocol diet works on inflammation in the gut, which is thought to be associated with autoimmune disease. Specifically, the AIP diet is thought to heal the immune system and the gut mucosa (lining), impacting inflammatory diseases, such as rheumatoid arthritis.

Is the AIP Diet the Same as the Paleo Diet?

The autoimmune protocol diet is considered the same as the Paleo diet by some. You will also see AIP called a “version” of the Paleo diet. Some say it is a stricter version of the Paleo diet. The principle behind the AIP diet is that autoimmune conditions are caused by “leaky gut” or altered intestinal permeability. In leaky gut, food leaks through tiny holes in the gut, provoking a response — actually an overreaction — by the immune system.

With the AIP diet, you eat foods that are rich in nutrients and steer clear of foods that are considered pro-inflammatory. Through diet, the goal is to not provoke an autoimmune response by the immune system. Summary of goals: Avoid irritating the gut with foods, heal holes in the gut, and reduce inflammation and other symptoms of autoimmune disease.

How the Autoimmune Protocol Diet Was Developed

The autoimmune protocol diet has been attributed to Loren Cordain, PhD, a scientist who discovered that certain foods can sometimes trigger inflammation in people with autoimmune disease. Author Robb Wolf outlined the autoimmune protocol in his book, The Paleo Solution, introducing it as an elimination diet. Sarah Ballantyne, PhD, (also known as The Paleo Mom) became interested in the autoimmune protocol, researched the science behind it, and wrote about it in her book, The Paleo Approach. Dr. Ballantyne is considered a leading expert on the autoimmune protocol.

Foods That Are Allowed and Disallowed on the Autoimmune Protocol Diet

The AIP diet allows you to eat:

Meat (preferably grass-fed) and fish
Vegetables, excluding nightshade vegetables
Sweet potatoes
Fruit in small quantities
Coconut milk
Avocado, olive, and coconut oil
Dairy-free fermented foods (such as kombucha, sauerkraut, kefir made with coconut milk, or kimchi)
Honey or maple syrup in small quantities
Fresh nonseed herbs (such as basil, mint, or oregano)
Green tea, and nonseed herbal teas
Bone broth
Vinegars
Grass-fed gelatin and arrowroot starch

The AIP diet does not allow you to eat:

All grains (including oats, wheat, and rice)
All dairy
Eggs
Nuts and seeds
Legumes and beans
Nightshade vegetables (tomatoes, potatoes, eggplant, peppers)
All sugars, including alternative sugars, such as stevia and xylitol
Butter and ghee (clarified butter)
Oils (other than coconut oil, olive oil, and avocado oil, which are allowed)
Herbs derived from seeds
Food additives or processed foods
Chocolate
Alcohol

Does the Autoimmune Protocol Diet Work for People With RA?

Researchers have been looking into the role of diet in leaky gut and autoimmune disease since at least 2012, per past research, and more current research, such as an article published in 2017 in Frontiers in Immunity, suggests that in some people leaky gut may be linked to the development of autoimmune disease. But there are still no conclusive clinical studies with regard to the role of diet in leaky gut and autoimmune disease.

Rheumatoid Arthritis Likely Has Multiple Causes and Risk Factors

According to research published in the journal FEBS Letters, “Rheumatoid arthritis is a multifactorial disease that involves both genetic and environmental factors. Among genetic factors, human leukocyte antigen (HLA) alleles provide the strongest risk, while among environmental factors, smoking and infections are involved. A role of hormones and changes in immune system during aging are also associated with pathogenesis of rheumatoid arthritis. All the factors that influence RA also impact the gut microbial composition. Gut microbiome provides a link between all the factors that influence RA. An individual may harbor a core gut microbiome and certain species may contract or expand depending on the exposure to various environmental factors, thus influencing the immune system locally in the gut as well as adaptive immune system.”

Some Research Suggests Diet Influences Gut Health, Which May Play a Role in RA Development

But, according to an article published in the February 2021 issue of the European Journal of Immunology, “Diet affects the composition of the gut microbiome and its secreted metabolites, another important environmental trigger. In the recent years it turned out that, a dybiosed gut microbiota correlates with the development of several chronic diseases including RA.

Still, besides the intensive research that was done to investigate the gut microbiota composition, the direct effects that cause a gut dysbiosis and its consequence to RA disease onset is not fully understood. Further, it still remains unclear whether dysbiosis is the cause or consequence of inflammation.”

What we have is more questions and we find ourselves without the answers.

There Appears to Be Gut Involvement in Rheumatoid Arthritis

There is no specific diet that has been proven to help RA. The impact of diet on RA remains theoretical. It’s trial-and-error at best. Essentially, it’s an elimination diet whereby you eliminate foods regarded as inflammatory and reintroduce them into your diet over time to see their effect on you individually. That’s the best we have at this stage because nothing about diet has been proven to help RA patients collectively.

A small study published in November 2017 in the journal Inflammatory Bowel Diseases concluded that the autoimmune protocol can have an effect on inflammatory bowel disease (IBD). There were 15 patients with either Crohn’s disease or ulcerative colitis enrolled in the study. They took six weeks to phase out the disallowed foods in the autoimmune protocol, followed by five weeks maintaining the protocol. Eleven of the 15 study participants had a complete remission. Great news for sure. But 15 is a very small study group — and there was no control group, and the study was not randomized.

Some Research Hints That AIP May Help Decrease Inflammation

A pilot study published in the April 2019 issue of Cureus, involving patients with Hashimoto’s thyroiditis (the most common form of autoimmune thyroid disease) suggested that the AIP diet and concomitant lifestyle modification, implemented by a multidisciplinary team, can be safely used as adjunctive treatments for people with Hashimoto’s thyroiditis already using thyroid hormone replacement therapy.

Results revealed no statistically significant changes in thyroid function or thyroid antibodies, but findings suggested that “AIP may decrease systemic inflammation and modulate the immune system, as evidenced by the decreases in average hs-CRP”

More Data Suggests AIP Shows Promise for Inflammatory Bowel Disease (IBD)

In October 2019, a small study published is Crohn’s and Colitis 360, involving 15 patients with inflammatory bowel disease (IBD) concluded that the AIP diet has the potential to significantly improve quality of life in a relatively short time frame — even during the elimination phase of the diet. Results suggested there were clinical benefits regardless of IBD medication use. While more long-term research is needed, the AIP diet has the potential to be an effective adjunctive therapy to conventional treatment.

The Bottom Line: We Are Short on Evidence That Would Link Diet and RA

While there is growing interest in the AIP diet for inflammatory diseases, there remains a need for larger, randomized clinical trials. Conclusive evidence is needed. Without it, the impact of diet on RA remains theoretical.

Does the Autoimmune Protocol Diet Help Rheumatoid Arthritis?