The autoimmune protocol (AIP) diet is designed to reduce inflammation and improve symptoms of autoimmune diseases. It follows an elimination protocol, where foods thought to cause inflammation are removed and then gradually added back in.
An autoimmune disease occurs when your body’s immune system mistakenly attacks and destroys healthy cells. This can lead to joint pain, fatigue, and an overall sense of not feeling well.
Early research suggests diet may play a large role in the prevention and treatment of autoimmune diseases. Examples include inflammatory bowel disease (IBD), rheumatoid arthritis (RA), type 1 diabetes, and lupus.
One theory is that certain foods, such as refined grains, red meat, added sugar, and fried foods, can damage the gut lining, causing a “leaky gut.” This may allow toxins to pass into the bloodstream, triggering an immune response and inflammation.
The AIP diet removes common food triggers. It focuses on healing the gut with anti-inflammatory foods, which may help reduce symptoms over time.
The AIP diet is a stricter version of the Paleo diet, which is a way of eating that mimics the diet of humans living during the Paleolithic era.
The AIP diet consists of three phases: elimination, reintroduction, and maintenance.
1. Elimination Phase
During this phase, multiple food groups, including grains, legumes, dairy, and eggs, are removed from the diet. Whole, minimally processed foods, fermented foods, and bone broth are encouraged. Lifestyle modifications, such as exercise, stress management, and sleep hygiene, are also recommended.
This phase lasts anywhere from six weeks to six months, depending on how quickly symptoms improve. In a study of people with IBD, some reported noticeable improvements within the first three weeks.
Keep in mind that restrictive diets like this one should be guided by a medical professional for individualization and prevention of nutrient deficiencies. Before starting any new eating plan, reach out to your doctor.
2. Reintroduction Phase
Once symptoms improve during Phase 1, eliminated foods are slowly reintroduced one at a time. Since people react differently, some foods may cause symptoms in one person but not affect another.
There are no official recommendations on how to reintroduce foods. Most people start with the foods they enjoy most or are more likely to tolerate.
Foods are grouped into four categories based on how likely they are to be well tolerated. Group 1 is most likely to be tolerated, while foods in Group 4 are more likely to cause symptoms.
- Group 1: Egg yolks, legumes, seed oils, nut oils
- Group 2: Nuts, seeds, cocoa, egg whites (and whole eggs), alcohol (small quantities)
- Group 3: Eggplant, coffee, fermented dairy
- Group 4: Remaining nightshade vegetables, all dairy, white rice, gluten-free grains, alcohol (larger quantities)
Here’s an example of how to reintroduce foods eliminated during Phase 1:
- Step 1: Reintroduce one food from a food group. Start with a small amount and gradually increase the portion to a normal amount over a few days.
- Step 2: Wait 5-7 days before trying another food. This gives your body time to respond if there’s an intolerance.
- Step 3: Repeat the process with another food.
- Step 4: Add foods that are well tolerated back into your diet. Re-eliminate those that cause symptoms.
The reintroduction phase can last up to three months.
3. Maintenance Phase
The maintenance phase is a long-term eating plan. It includes foods you tolerate well while avoiding your individual trigger foods. The goal is to keep symptoms under control. At this time, there isn’t much long-term research on the effects or benefits of the AIP maintenance phase.
The AIP diet includes fresh, minimally processed foods. Your meals will consist mainly of vegetables, fruits, lean proteins, and healthy fats.
During the elimination phase of the AIP diet, you can eat:
- Meat, seafood, and poultry: Grass-fed or wild-caught beef, chicken, fish (tuna, mackerel, mahi, tilapia, cod, catfish, trout), shellfish (clams, crab, crawfish, lobster, oysters, scallops, shrimp)
- Fresh fruits and vegetables: All except those in the nightshade family and algae
- Oils and fats: Coconut oil, olive oil, avocado oil, avocado, olives
- Herbs and spices: All types not derived from seed oils, including rosemary, cinnamon, turmeric, thyme, oregano, ginger, sage, basil, bay leaf, peppermint, garlic, parsley, mint
- Non-dairy fermented foods: Sauerkraut, kombucha, pickled vegetables, kimchi, apple cider vinegar
- Sweeteners: Honey, maple syrup, coconut sugar, date sugar, dried fruits
- Drinks: Water, herbal teas (chamomile), green tea
During the elimination phase, all foods that may trigger an autoimmune response are eliminated. This includes:
- All grains: Barley, corn, millet, oats, rice, rye, sorghum, wheat, crackers, pasta, quinoa, amaranth, tapioca, buckwheat, potato flour
- Eggs: Whole eggs and egg derivatives like mayonnaise
- All nuts and seeds and their oils: Almonds, walnuts, cashews, sesame, flax seeds, hazelnuts, hemp seeds, macadamia nuts, pecans, pine nuts, pistachios, chia seeds, canola oil, almond flour/milk, tahini
- Herbs and spices derived from seeds: Black caraway, celery seed, coriander, cumin, dill, fennel, fenugreek, mustard, nutmeg
- Nightshade vegetables: Bell peppers, cayenne peppers, chili peppers, eggplant, goji berries, regular potatoes, pimentos, tomatoes, ketchup
- All milk and dairy: Yogurt, butter, kefir, milk, cheese, cream
- Sweeteners and additives: Table sugar, brown sugar, agave, artificial sweeteners (stevia, aspartame, sucralose, etc.), food additives, emulsifiers, inulin, lactose
- Drinks: Sugary beverages, coffee, alcohol, fruit juice
Here is what a day of eating during the elimination phase of the AIP diet may look like:
- Breakfast: Sweet potato hash with ground turkey and spinach sautéed in olive oil
- Lunch: Green salad with grilled chicken, avocado, cucumber, and shredded carrots, drizzled with olive oil and apple cider vinegar dressing
- Dinner: Grilled salmon with roasted carrots and steamed broccoli
- Snacks: Bone broth, fresh fruit, dried meat
The main benefit of the AIP diet is its potential to reduce symptoms of autoimmune conditions. Specifically, limited research has shown that it may help improve the quality of life and reduce symptoms in people with:
- Hashimoto’s disease: A small study of people with Hashimoto’s disease found that after following the AIP diet for 12 weeks, fewer participants reported feeling unwell. Improvements were also seen in thyroid size, thyroid hormone levels, and weight loss. Another study in people with Hashimoto’s did not show improvements in thyroid function but did find a 29% decrease in inflammation markers.
- Irritable bowel disease: Small studies have shown improvements in symptoms and inflammation in people with Crohn’s disease and ulcerative colitis.
- Rheumatoid arthritis: In a small, early study of people with rheumatoid arthritis, a 12-week AIP diet intervention was associated with improved sleep, joint pain, and fatigue.
While studies are promising, more research is needed to understand how the AIP diet may benefit autoimmune conditions.
The AIP diet can be safe when followed under the guidance of a qualified healthcare professional. However, there are potential risks. Since the diet cuts out many nutritious foods, you might not get enough essential nutrients. The risk of nutrient deficiencies can increase the longer you stay in the elimination phase without adding foods back.
Also, some studies show that the AIP diet might cause bowel blockages in people who have strictures (narrowing in their intestines). This is likely due to a high consumption of raw vegetables and the diet’s high fiber content.
The following groups of people should avoid the AIP diet unless recommended by a healthcare provider:
- Pregnant or breastfeeding people
- Older adults
- People who are underweight or malnourished
- People with a history of intestinal strictures
- People with a history of malabsorption, where the intestines do not effectively absorb nutrients
- People with a history of an eating disorder
Drawbacks
The AIP diet cuts out several food groups, making it very difficult to follow. Preparing AIP-compliant meals can also be time-consuming. The diet’s restrictive nature may cause feelings of social isolation or stress when dining out with others.
Some people feel worse before they feel better when starting the AIP diet. They may experience headaches, fatigue, or mood changes, especially if they cut out foods like caffeine. These symptoms usually last a few days to a week.
Additionally, not everyone may have access to or be able to afford a registered dietitian nutritionist, which is important when beginning the diet.
The AIP diet is an elimination diet with three phases. It’s designed to remove potential food triggers and gradually add them back. The goal is to identify foods that may cause symptoms related to autoimmune conditions.
Research on the benefits of the AIP diet is limited, but some studies suggest it may help improve inflammation and pain, among other symptoms.
Due to the diet’s restrictive nature, it should only be followed under the close supervision of a healthcare provider or registered dietitian nutritionist.
