Every day it seems that there is a new diet claiming to help those with digestive disorders. Although the low FODMAP diet has been well-known and proven to help those with irritable bowel syndrome reduce symptoms, the Autoimmune Protocol (AIP) diet is perhaps not as well-known.  The AIP diet focuses on eliminating foods that may cause inflammation in the gut.  This diet has been used by those with autoimmune diseases like rheumatoid arthritis and lupus to help reduce pain and fatigue.

However, those who believe they may suffer from leaky gut syndrome, are also looking to this diet for relief.  Although this syndrome has not been officially recognized as a gastrointestinal diagnosis, it is believed that some individuals may experience inflammation of the gut as well as malabsorption issues due to a defect in their gut where bacteria and other toxins are “leaked” into the bloodstream.  The AIP diet is thought to help reduce the inflammation caused by this as well as by other digestive conditions such as SIBO, or small intestinal bacterial overgrowth. Let’s explore the differences between these two diets to see which one may be the best fit for you.

The Autoimmune Protocol (AIP) diet

You may have heard of the paleolithic diet, which is thought to focus only on those foods that the body was designed to digest. It focuses on lean meats (preferably grass-fed), seafood (preferably wild-caught), eggs, low-starch fruits and vegetables (preferably organic), nuts and seeds, and plant-based oils like olive oil. Some versions of the paleolithic diet may allow some ghee and potatoes. The AIP diet is basically the paleolithic diet, but a bit stricter to help eliminate any inflammation-causing foods in order to help heal the gut.

Like the paleolithic diet, the AIP diet avoids all dairy, grains, legumes, alcohol, and processed food products like refined sugars. However, it is a bit stricter than the paleolithic diet in that certain foods that may be allowed on the paleolithic diet are not allowed. Examples of such foods off limits on the AIP diet are nightshade vegetables like tomatoes, eggplants, peppers, and potatoes, as well as all oils except for coconut, olive, and avocado oils.  

Therefore, the AIP diet would include the following foods:

• Meat and fish, preferably grass-fed
• Vegetables (except for the nightshade vegetables)
• Sweet potatoes
• Fruit, in small quantities
• Coconut milk
• Avocado, coconut, and olive oil
• Dairy-free fermented foods such as kefir made with coconut milk, sauerkraut, kimchi, and kombucha
• Honey or maple syrup in very limited quantities
• Green tea and non-seed herbal teas
• Fresh non-seed herbs such as basil, mint, and oregano
• Bone broth
• Vinegars such as apple cider or balsamic

The diet is not meant to be followed strictly for the long-term, but just for several months before experimenting with adding foods in. It may be beneficial to have a healthcare provider supervise the transition phase to help you identify trigger foods for your inflammatory symptoms.

How is low FODMAP different?

The low FODMAP diet is different from the AIP diet in several ways.  First of all, the theory behind the low FODMAP diet is that certain compounds in some foods are not tolerated well by those with digestive conditions. These compounds are fermentable oligosaccharides, disaccharides, monosaccharides, and polyols. In simpler terms, the low FODMAP limits foods and drinks that contain compounds such as:

• Lactose, or milk sugar, found in animal milk and milk products.
• Fructose, or fruit sugar as well as processed forms of this sugar like high fructose corn syrup. Also, fruits that are high in fructose like apples, watermelon, cherries, blackberries, pears, and peaches should be avoided on the low FODMAP diet.
• Sugar alcohols like xylitol, mannitol, erythritol, and sorbitol, commonly found in sugar-free processed foods and drinks, as well as sugar-free gum.
• Plant-based foods such as garlic, onion, asparagus, Brussels sprouts, legumes, as well as nuts like cashews and pistachios, and limited amounts of almonds.
• Grains such as wheat and rye.

Typically, the diet would be followed strictly for two to eight weeks. After that time, foods would slowly be added in to help identify which are the major trigger foods.  This process should be supervised by a qualified healthcare practitioner such as a registered dietitian familiar with the low FODMAP diet, to help ensure a safe transition from the elimination diet.

So, what diet is right for me?

Both diets focus on consuming whole foods and eliminating processed foods. They are also similar in avoiding gluten, but the AIP diet does not allow any grains at all. The AIP diet and low FODMAP diet have varying allowances for vegetables and herbs, as well as for fruits and nuts. Therefore, it is hard to say which one will work for you best. It will have to be a process of elimination on either diet you try to see which foods are your trigger foods for symptoms. 

Like with any diet, the best one for you is the one that you will be able to follow and that will make you feel better. No one diet is the complete solution for any health condition, and therefore a qualified healthcare provider should be part of your treatment process to help you find a holistic approach to your healing. Read more on Casa de Sante for the latest news on digestive healing diets like the low FODMAP diet and product recommendations and resources for your healthy lifestyle.

For more information, resources and products for the AIP diet and other therapeutic diets that may help with your digestive symptoms, visit the Casa de Sante website

Written by Staci Gulbin, MS, RD a Board-certified dietitian.