How long should I stay on an AIP diet? Understanding the Phases

November 15, 2025 •

4 min read

The prevalence of autoimmune diseases has been on the rise globally, with studies indicating that millions of Americans are affected. Many turn to the Autoimmune Protocol (AIP) diet to help manage their symptoms, and a common question is: how long should I stay on an AIP diet? The duration is not fixed but is a personalized journey through distinct phases.

Quick Summary

The AIP diet involves a temporary elimination phase (30-90 days), followed by a methodical reintroduction of foods to identify personal triggers. The ultimate goal is a balanced, personalized maintenance diet, not indefinite restriction.

Key Points

Elimination Phase is Short-Term: The strict elimination phase of the AIP diet typically lasts 30 to 90 days, not indefinitely.
Start Reintroduction After Symptoms Improve: You should wait until you experience a noticeable reduction in autoimmune symptoms before beginning the reintroduction phase.
Individual Timelines: The total duration of the AIP diet is highly individual and depends on your health status and how quickly you heal.
Reintroduction Requires Patience: Each new food should be tested one at a time with a 5-7 day waiting period to monitor for delayed reactions.
Maintenance is Personalized: The long-term goal is to transition to a personalized maintenance diet, keeping only your specific trigger foods permanently removed.
Seek Professional Guidance for Delays: If your symptoms don't improve after 90 days in the elimination phase, consult a functional health practitioner to investigate other factors.

The Autoimmune Protocol (AIP) is not a lifelong sentence of strict food restriction but rather a structured, multi-phase process designed to identify your specific food sensitivities and promote gut healing. The duration of your AIP journey depends on your individual health needs and how your body responds to each stage. This article explores the typical timeline for each phase and key factors that influence how long you should stay on an AIP diet.

The Three Phases of the AIP Diet

Phase 1: Elimination

This is the most restrictive phase, where you eliminate foods and ingredients known to cause inflammation, gut irritation, or immune responses. Common foods to remove include grains, legumes, dairy, eggs, nightshade vegetables, nuts, seeds, alcohol, coffee, and processed sugars.

How long does the elimination phase last?

Minimum Duration: Most experts recommend staying in the elimination phase for at least 30 days. This provides enough time for systemic inflammation to decrease and for you to notice initial improvements in your symptoms, such as reduced joint pain, fatigue, or digestive issues.
Optimal Duration: Many individuals, particularly those with multiple or long-standing autoimmune conditions, benefit from a longer period of 60 to 90 days. This allows for more significant gut healing and gives the body a better chance to stabilize before beginning reintroductions.
Maximum Duration: Staying in the elimination phase for longer than 6 months is generally not advised without professional guidance due to the risk of nutritional deficiencies. If you haven't seen significant symptom improvement after 90 days, it is recommended to work with a practitioner to troubleshoot other potential root causes of your inflammation.

Phase 2: Reintroduction

Once you experience a noticeable and stable reduction in your symptoms, you can begin the reintroduction phase. The goal is to slowly and systematically reintroduce eliminated foods, one at a time, to determine what you can safely tolerate.

How long does the reintroduction phase last?

Timeline Varies: The length of the reintroduction phase is highly individual and can take several months. This depends on how many foods you choose to retest and how your body reacts to each challenge.
Methodical Process: Each reintroduction requires a multi-day protocol. You test a small amount of a single food on one day, then avoid it for 5–7 days while monitoring for any symptom flare-ups. This slow approach is crucial for accurately identifying triggers. For example, testing ghee and then waiting a full week before testing egg yolks will prevent confusion if a reaction occurs.
Focus on Tolerance: The process helps you understand your body's specific tolerances. If a food causes a reaction, you remove it again and can potentially try reintroducing it later, when your gut has healed further.

Phase 3: Maintenance

After completing the reintroduction phase, you transition into the maintenance phase, which represents your new, personalized, long-term diet. This eating plan is based on the foods you found you can tolerate without triggering autoimmune symptoms.

How long does the maintenance phase last?

Indefinite Duration: This is your new sustainable way of eating and can be followed indefinitely. It is not as restrictive as the initial elimination phase. You will continue to avoid only the specific foods that cause you issues and incorporate all the foods you successfully reintroduced.
Periodic Re-testing: It is important to remember that food tolerances can change over time as your gut health improves. Foods that failed a reintroduction test initially may be tolerated later on, so periodic re-testing is an option.

Factors Influencing Your AIP Timeline

Several variables can affect the length of time you spend on the AIP diet and its phases:

Severity and Duration of Autoimmune Disease: Those with more severe or longer-standing conditions may need a longer elimination phase to allow for deeper healing.
Strictness of Adherence: Following the protocol strictly during the elimination and reintroduction phases yields the clearest and fastest results. Cheating can prolong the process by causing inflammation flares that disrupt the healing process.
Gut Health Status: The health of your gut plays a central role in your immune response. Individuals with more significant gut issues, such as "leaky gut," may require a longer period of elimination.
Lifestyle Factors: The AIP protocol also emphasizes lifestyle changes to reduce inflammation, including stress management, adequate sleep, and gentle exercise. Neglecting these factors can hinder your healing and extend your time on the protocol.

AIP Phases: A Comparative Look


Feature	Elimination Phase	Reintroduction Phase	Maintenance Phase
Goal	Reduce inflammation and heal the gut lining	Identify individual food triggers	Establish a personalized, sustainable long-term diet
Foods Eaten	Only nutrient-dense, AIP-compliant foods	All AIP-compliant foods + newly reintroduced foods	All tolerated foods (most inclusive)
Duration	30–90 days (approx.)	Varies (several weeks to months)	Indefinitely
Dietary Approach	Highly restrictive	Methodical and cautious	Personalized and flexible
Key Outcome	Symptom reduction and baseline stability	Identification of food sensitivities	Sustained symptom management and overall wellness

A Note on Professional Guidance

While the AIP framework provides clear guidelines, navigating the process can be challenging, especially for those with complex health issues. Working with a functional medicine practitioner or an AIP-certified nutritionist can provide tailored advice and support. They can help you troubleshoot challenges, ensure you are meeting your nutritional needs, and guide you through reintroductions effectively.

Conclusion

The answer to "how long should I stay on an AIP diet?" is that the strict phase is temporary, typically lasting 30 to 90 days. The complete journey, including reintroduction and maintenance, is a personal process designed to help you discover a sustainable, anti-inflammatory eating pattern for life. This is not about permanent restriction but about creating a more inclusive diet by identifying and avoiding only your specific food triggers. By listening to your body and taking a methodical, patient approach through each phase, you can manage your autoimmune symptoms and improve your long-term health.

For more in-depth information on the reintroduction process, Dr. Sarah Ballantyne (the Paleo Mom) offers a detailed four-phase chart based on nutrient density and reactivity potential.

Frequently Asked Questions

The AIP elimination phase typically lasts between 30 and 90 days. However, some individuals with severe conditions may require a longer period, while others notice improvements in as little as three weeks.

You are ready to begin reintroduction when you have experienced a significant and consistent reduction in your autoimmune symptoms and overall inflammation. It's best to feel stable and have your symptoms well-managed before proceeding.

No, the strict AIP diet is not a lifelong plan. The goal is to use the elimination phase to heal the gut and identify food triggers, then transition to a personalized, less restrictive maintenance diet based on what you can tolerate.

The reintroduction phase can last several months, as you must introduce one food at a time, followed by a waiting period of 5 to 7 days to observe for reactions. The total time depends on the number of foods you retest.

If you don't see symptom improvement after 90 days, it is recommended to work with a functional health practitioner or an AIP-certified nutritionist. They can help identify other factors contributing to inflammation, such as stress or nutrient deficiencies.

After reintroduction, you enter the maintenance phase. This is a personalized, long-term way of eating that incorporates all the foods you successfully reintroduced while continuing to avoid your specific trigger foods.

Yes, it is possible to re-test foods that you initially failed to tolerate. As your gut continues to heal over time, your body's tolerance to certain foods may change. You should wait a few weeks or months before attempting a re-test.