What Is The GAPS Diet? Everything You Need To Know About This Powerful Gut-Healing Tool

As a functional medicine practitioner who talks a lot about gut health, it’s my job to shed light on all the tools available to you to heal your gut. One of these tools being the GAPS diet. This protocol has been used for years to treat symptoms of a damaged gut but has come under criticism for its restrictive nature. So while the GAPS diet may indeed be on the restrictive end when it comes to diets, its foundation is rooted in functional medicine principles of what is good for your gut. Read on to learn more about this diet and whether or not it is a good choice for you and your gut healing journey.

What is the GAPS diet?

Short for Gut and Psychology Syndrome, The GAPS diet is a tool designed to address the connection between your gut and various chronic health conditions, specifically ones that involve your brain such as anxiety, depression, autism spectrum disorders, ADHD, and dyslexia. 

Developed by Dr. Natasha Campbell-McBride in 2004, the GAPS diet is rooted in the idea that a damaged gut lining (also known as leaky gut syndrome) also affects your brain health (a principle referred to as the gut-brain axis connection). 

By eliminating processed foods, grains, starchy vegetables, and sugars while emphasizing nutrient-dense whole foods, a person can begin to heal the gut lining through enhancing gut microbiome diversity and reducing inflammation in both the digestive system and brain.

The GAPS diet is made up of three stages:

• The Introduction Phase (elimination)
• The Maintenance Phase (the diet itself)
• Reintroduction Phase (transitioning out of the diet)

The Introduction Phase

This phase of the GAPS diet lasts anywhere between three weeks to one year, depending on the severity of your symptoms. It is the most difficult phase of the entire diet because of how restrictive it is in terms of what you are allowed to eat.

The phase is broken up into six stages. You start with a base list of foods in stage one and slowly add in a few more foods as you move through each stage.

• Stage 1: Bone broth, boiled meat or fish, cooked vegetables, ginger and chamomile tea or other herbal teas (with raw honey if desired), probiotic-rich fermented foods like yogurt, kefir, and fermented whey, purified water, and other probiotic foods
• Stage 2: Add in organic raw egg yolks, fermented fish, meat and vegetable-based casseroles or stews, homemade ghee, and coconut oil
• Stage 3: Add in avocado, fermented vegetables and sauerkraut, scrambled eggs made with ghee, goose, or duck fat, GAPS-recipe pancakes made with nut flours, probiotic supplements
• Stage 4: Add in cold-pressed olive oil, roasted or grilled meats, fresh-pressed carrot juice, GAPS-recipe milkshakes, GAPS-recipe bread
• Stage 5: Add in cooked apple puree, fresh-pressed fruit juice, raw vegetables like lettuce
• Stage 6: Add in raw fruit, raw-peeled apples, baked goods made with dried fruit

In order to determine when it is time to move to the next stage, you must experience normal bowel movements on a consistent basis and tolerate each food in the current stage you are in without any reactions. Once every stage of the introduction phase is complete — however long that takes — you’ll move on from the introduction diet to the full GAPS diet, also known as the maintenance phase.

The Maintenance Phase

This phase of the GAPS diet lasts anywhere between 1.5 to 2 years. During this time, your diet should only consist of:

• Fish and shellfish (wild-caught whenever possible)
• Animal protein (organic, grass-fed, and pasture-raised whenever possible)
• Vegetables
• Organic eggs
• Fermented foods (kefir, yogurt, sauerkraut)
• Animal fats (duck fat, raw butter, ghee, tallow, lard, etc.)
• Nuts (in moderation)
• GAPS-recipe baked goods (in moderation)

In addition, the GAPS diet recommends that you stick to the following principles throughout the duration of the maintenance phase:

• Choose organic options as much as possible
• Eat as much fermented foods as possible
• Don’t eat meat and fruit together
• Don’t eat pre-packaged or canned foods
• Don’t eat refined carbohydrates
• Don’t eat preservatives, artificial colorings, and additives

One of the biggest recommendations and hallmarks of the GAPS diet is to drink bone broth alongside every meal. Due to its intensive gut healing properties, having bone broth on a regular basis is believed to help speed up the healing benefits of the GAPS diet.

READ MORE: Bone Broth Benefits: A Functional Medicine Guide To This Ancient Superfood (+ Recipes & Vegan Alternatives)

The Reintroduction Phase

Once you have been on the GAPS diet for the recommended 1.5-2 years, it is time to enter the reintroduction phase and start reintroducing foods you haven’t been eating during this time. To determine if you are ready to enter the reintroduction phase, you must be experiencing normal bowel movements and zero digestive distress for a minimum of 6 months.

The length of this phase can vary as you slowly reintroduce foods one by one over a period of time in order to assess for any reactions. Since you aren’t reintroducing foods all at once, and depending on if you have a reaction, this phase can last anywhere between a few months to a year.

Although the GAPS diet doesn’t have a specific order of reintroduction, they do advise that you only eat a small amount of each new food to start and wait 2-3 days before upping your portion size and moving on to the next food you want to reintroduce.

Supplements on the GAPS diet

While the GAPS diet doesn’t require you to take specific supplements, some are recommended to help assist with gut healing, encourage further progress, and ease any symptoms or side effects during the healing process. These include:

• Digestive enzymes
• Probiotics
• Cod liver oil
• Oxbile
• Seagreens Seaweed
• Activated charcoal
• Diatomaceous earth
• Butane HCI with Pepsin

SHOP: To elevate the probiotic experience I formulated LongevityRX Probiotic Trillion, a 4-in-1 gut health formula featuring prebiotics, probiotics, postbiotics, and parabiotics. Powered by fast-acting spore-based strains like Bacillus subtilis AB-22, it helps reduce inflammation, restore gut lining integrity, and support immune resilience — all things that need a little boost during this transitional healing period of the GAPS diet (or whatever healing journey you are on). In fact, 80% of people reported improved digestion and regularity and 79% felt less bloated after meals. 

Life after the GAPS diet

After going through each phase of the GAPS diet, you should experience a significant reduction, or reversal, of your symptoms while also curating a diet that works for your specific health case based on the reintroduction phase. Once you know what foods cause a reaction for you, you should continue to avoid them for the foreseeable future while also avoiding processed foods high in sugar. The goal should be to stick to clean, whole-foods as much as possible.

What does the research say about the GAPS diet?

As a functional medicine practitioner, I am often asked about the research surrounding the GAPS protocol. While the GAPS diet is based on the principle of healing the gut-brain axis, it is important to note that there is limited research specifically looking at this protocol. However, a few emerging studies found that a GAPS protocol was able to help ease symptoms of a few conditions such as PANDAS and tics. (1,2)

The research surrounding the link between gut dysbiosis, its impact on the gut-brain axis, and various conditions like autism, ADHD, and depression are more well-documented though, which shows a lot of promise for the GAPS diet as healing the gut is the foundation of the GAPS approach. (3,4,5) Additionally, research on the benefits of a diet rich in nutrient-dense foods, bone broth, and fermented foods aligns with the GAPS diet’s emphasis on gut healing. 

Nevertheless, more rigorous clinical trials and long-term studies are necessary to establish the efficacy and safety of the GAPS protocol fully. As with any functional medicine approach, individual responses may vary, and it is crucial to work with a qualified healthcare professional to tailor the GAPS protocol to suit specific needs and health conditions.

LISTEN: PANS, PANDAS, Chronic Lyme & Neuroinflammation: What Doctors Miss | Dr. Eboni Cornish

The Takeaway

In general, the GAPS diet has a lot of similarities to other gut healing, anti-inflammatory diets including a standard elimination diet and AIP diet (autoimmune inflammatory protocol). Ultimately, whether or not the GAPS diet is right for you comes down to your individual health case. In my telehealth functional medicine clinic, we run a variety of diagnostic functional medicine labs to get to the root cause of your chronic symptoms in order to determine the best plan of action to facilitate healing. In some cases, the full GAPS diet might be the right fit, and in other cases some modification may need to be made depending on what is happening beneath the surface. 

If you are dealing with chronic health problems and considering a GAPS diet, schedule a telehealth consultation today to learn more about how we can help you using functional medicine. By taking a whole-body approach to wellness, we look at all areas of your health in addition to diet including stress, toxin exposure to come up with a healing plan that works for you and your unique biochemistry.

As one of the first functional medicine telehealth clinics in the world, we provide webcam health consultations for people around the globe. 

Photo: Unsplash.com

Sources

• Delaunay-Vagliasindi S, Seneff S, Coro S & Campbell-McBride N (2021) GAPS Nutritional Protocol as a treatment for PANDAS: A case study. J Orthomol Med. 36(3)
• Delaunay-Vagliasindi S et al. (2022) Why the GAPS Nutritional Protocol is a Promising Treatment for Tics and Tic-Related Disorders: Analysis of Six Case Studies. J Orthomol Med.
• Guo, Y., Liu, A., Hao, X., Cao, X., Li, Y., & Liu, X. (2026). The gut microbiota, neurodevelopment and autism spectrum disorder: A close connection. Progress in neuro-psychopharmacology & biological psychiatry, 148, 111811. https://doi.org/10.1016/j.pnpbp.2026.111811
• Steckler, R., Magzal, F., Kokot, M., Walkowiak, J., & Tamir, S. (2024). Disrupted gut harmony in attention-deficit/hyperactivity disorder: Dysbiosis and decreased short-chain fatty acids. Brain, behavior, & immunity – health, 40, 100829. https://doi.org/10.1016/j.bbih.2024.100829
• Lin, S. K., Chen, H. C., Chen, I. M., Hsu, C. D., Huang, M. C., Liu, C. M., Wu, S. I., Chen, P. Y., Chen, C. H., & Kuo, P. H. (2025). Dysbiosis and depression: A study of gut microbiota alterations and functional pathways in antidepressant-naïve mood disorder patients. Translational psychiatry, 15(1), 290. https://doi.org/10.1038/s41398-025-03521-1
• GAPS Diet. (2021). Full GAPS diet: Quick start guide. https://www.gapsdiet.com/wp-content/uploads/2021/01/FullGAPSDiet-1.pdf