We finally have a study specifically looking at the efficacy of the Autoimmune Protocol Diet, also known as the Autoimmune Paleo Diet or AIP, and Hashimoto’s disease. The exact title of the paper is, “Efficacy of the Autoimmune Protocol Diet as Part of a Multi-disciplinary, Supported Lifestyle Intervention for Hashimoto’s Thyroiditis” by Abbott et al. Published in April of 2019 in the journal Cureus. I break down the study details below so you can better understand if this diet actually works for Hashimoto’s disease.
I have written before about the Autoimmune Paleo Diet but this was on a paper looking at inflammatory bowel disease which did show some promising results.
The authors begin the study by stating some of the potential causes of Hashimoto’s thyroiditis including genetic and environmental factors, pregnancy, drugs, nutritional intake, vitamin D receptor defects and infections. They also state something very important which is the fact that individuals with Hashimoto’s disease who are treated with thyroid medication tend to continue to have a reduced quality of life and chronic symptoms like fatigue, nervousness, dry skin, hair loss, and irritability even though their thyroid numbers look fine.
I also liked the fact that they stated there isn’t enough evidence that goitrogens consumed in moderation negatively impact thyroid function.
How was this study done?
17 subjects between the ages of 20-45 with Hashimoto’s disease began the study but only 16 finished due to one of them getting pregnant. They couldn’t have been following the AIP diet within 30 days of starting the trial and it was ok for them to be taking thyroid medication. Subjects did a 2-week washout period and filled out symptom and food questionnaires.
The following blood tests were done:
- Total and Free T4
- Total and Free T3
- Reverse T3
- Thyroid peroxidase antibodies (TPO)
- Anti-thyroglobulin antibodies (TGA)
- Complete blood count (CBC)
- Complete metabolic profile (CMP)
- Vitamin D
- Highly-sensitive C-reactive protein (hs-CRP)
And surprisingly they did an organic acids test and a stool analysis. A stool analysis is vital for those with Hashimoto’s disease to identify infections like H. pylori, Blastocystis hominis, and Yersinia enterocolitica. Organic acids gives a detailed view of overall metabolism so we know how well someone is making energy from fat, protein, and carbohydrates as well as detoxification, gut health markers, neurotransmitters, and certain amino acids, vitamins and minerals.
After the two week washout period, the subjects started a 10-week process including:
-Six weeks of food elimination which included gluten, all grains including gluten-free grains, dairy, nuts, legumes, nightshades, eggs, coffee, alcohol, seeds, refined sugars, oils, and food additives.
-More nutrient-dense foods including bone broth, fermented foods, seafood, organ meats, and more mono and polyunsaturated fats.
-Lifestyle modifications including sleep hygiene, support systems, stress management, movement, and more time outdoors.
-A four-week maintenance phase with no food reintroductions.
All participants had the support of health coaches and NTP’s who helped them with menu planning, grocery shopping, recipes, cooking, and lifestyle modification suggestions. Unfortunately, the participants engaged in a private Facebook group despite the fact the Facebook has been shown to cause anxiety and depression.
Once the 10 week intervention was over the subjects repeated all of their lab tests and questionnaires to see how they responded.
Did the Autoimmune Paleo Diet yield good results for Hashimoto’s thyroiditis?
All of the symptoms measured in the questionnaires improved and the symptom burden decreased significantly. None of the thyroid blood tests changed with any significance including TSH, total and free T4, total and free T3, and the thyroid antibodies did not change either. Inflammation did however decrease significantly as measured by the highly-sensitive C-reactive protein test. There was also a shift in the white blood cell count for the better indicating improved immune system function.
The author’s conclude that this dietary and lifestyle intervention is successful in reducing inflammation, improving immune system function, and reducing the symptoms associated with Hashimoto’s thyroiditis.
One interesting thing to note is that 6 of the study participants were able to reduce their thyroid medication. And 3 of these women were able to decrease their dose even further after the full 10-week program.
The authors make a very important point about the community support that each participant received through the online group and coaching support. Following a restrictive diet can be stressful and adherence is low in many people. The participants were set up for success from the beginning due to all of the support they received.
The weaknesses of the study are clear including a lack of a control group, small sample size, lack of blinding, selection bias of the participants, and a response bias of reported weight. The symptom questionnaire they used is not a validated form of symptom tracking. And there was a lack of data on how well the participants were sleeping, physical activity, social support, stress levels, and there was no reintroduction of foods that were eliminated.
Dr. Hedberg’s Comments
This is a great start to studying the potential benefits of diet on Hashimoto’s disease. There are many obvious weaknesses as noted above but the authors had to start somewhere.
We still don’t know if all of the foods in the Autoimmune Paleo Diet need to be eliminated or if the results would be the same just eliminating gluten, dairy, and sugar for example. Some people may do fine with some nuts or some rice or some lentils etc. etc. It will be extremely difficult to ever study this however as large numbers of study participants would have to avoid specific foods for long periods of time and compare them to other groups avoiding different foods.
The study participants knew that they were following the Autoimmune Paleo Diet so they knew they were following a diet that is designed to treat the condition they have. This creates a major problem in the results because we know from the psychoneuroimmunology research that what we believe directly changes our biochemistry.
If you have allergies and you take a sugar pill but are told that the pill is a drug designed to treat allergies, approximately 60-70% of those who take it will see improvement in their allergies. In fact, some patient’s allergies will completely go away when they take it. If you’re told that you’re following a diet to treat this or that condition, you’ll have a similar positive response in most cases. This is why blinding is so important in research so we can remove this bias.
One would expect inflammation to decrease as found in this study by removing gluten and dairy from the diet. Again, we don’t know if all the additional food restrictions are necessary to reduce inflammation and see improvements.
None of the thyroid numbers changed, not even a drop in thyroid antibodies. But after looking in detail at the data, most of the participants had antibody levels <500 so they were clinically insignificant to begin with. Perhaps following the diet for longer periods would show improvement in thyroid numbers.
The biggest variable is the community support and the support of the health coaches, nutrition professionals, and the doctors. We know that people begin to make better food choices when they have community support. Additionally, community and practitioner support can reduce inflammation, improve mood, and improve important neurotransmitters and hormones like oxytocin and serotonin. So we don’t know what would have happened without all of this support or if the study participants did have the support but just followed a healthier diet.
There are so many unknowns but this is a promising start. I applaud the researchers for taking the first step in studying diet and Hashimoto’s disease.