You can use the categories located to the right of this post and click 'Hashimoto's Research Update' to see all of the updates.
What if you have elevated thyroid antibodies but your TSH isn’t elevated yet, ie it’s Hashimoto’s Thyroiditis (HT) but not yet progressed to hypothyroidism? Conventionally patients are often told to just watch and wait. Wait until it turns into hypothyroidism, then you can take medication.
This study published in 2016 demonstrated that supplementing with vitamin D actually reduced thyroid antibodies and prevented the progression of HT into hypothyroidism. So there is something you can do instead of just watch and wait.
One limitation of this study is that it was performed in Turkey, a country with notoriously low vitamin D levels. The average vitamin D level in patients with HT entering the study was 9 and the control group average was 12! During the study all of the groups raised their vitamin D blood levels to around 50. So it’s important to test your vitamin D levels. If you are already around 50/60 you likely wouldn’t benefit from additional vitamin D supplementation.
The Composition of Gut Microbiota in Patients Bearing Hashimoto's Thyroiditis with Euthyroidism and Hypothyroidism (2020)
This study compared the gut microbiome between three groups; normal controls, people with Hashimoto’s but normal thyroid function (HT), and people with Hashimoto’s and hypothyroidism (HTH). This study consisted of 97 people all from a particular region in China. The researchers found that the richness of diversity in the gut microbiome was significantly lower in HT patients than in the control group. The patients with HTH had the least microbial abundance. Our gut microbiome plays a vital role in our immune system so it makes sense that shifts in the microbiome could be playing a role in autoimmune diseases. Something else to consider is that thyroid hormones also influence the function of our GI, especially motility. It’s possible the change in diversity from HT to HTH could be partly due to the influence of low thyroid hormone on GI function.
This research further confirms why it’s so important to nurture a healthy gut microbiome.
Psychological Wellbeing in Hashimoto’s (2017)
The main finding of this study is that health related quality of life is impaired in euthyroid Hashimoto’s patients. Let’s break this down a bit. Euthyroid Hashimoto’s Thyroiditis (HT) is when a patient has thyroid antibodies and/or Hashimoto’s specific abnormalities on thyroid ultrasound but a normal TSH. This study evaluated the quality of life for HT’s patients and found that HT’s patients had lower quality of life regarding physical functioning, general health and mental health. Specifically this study found that patients with euthyroid HT had increased levels of both anxiety and depression. Interestingly, this study included a group of euthyroid HT patients that were taking levothyroxine and a group not taking any medication. There were no differences between these two groups in terms of depression, anxiety or quality of life scores. So medication did not improve these symptoms.
My patients are consistently told by endocrinologists if they are on medication and their TSH is normal then their symptoms are not from Hashimoto’s. Not true. Evidence is mounting that there are deeper mechanisms here.
Another nugget from this paper that I have to directly quote, it’s so good! “TSH levels were slightly higher in HT group than control group although all the participants were in euthyroid state in our study. Higher TSH levels were also found in previous studies comparing euthyroid HT and control subjects. These findings might suggest that slightly higher TSH even in the normal range might be related with impairment in psychological well-being in patients with euthyroid HT.” One more time for the folks in the back! HT patients have been fighting to be heard around this issue for such a long time. It’s time to reevaluate the ‘normal’ range for TSH especially in HT patients.
Effect of Low Carbohydrate Diet in Autoimmune Thyroiditis (2016)
The title is misleading because they changed a lot more about the diet than just carbohydrate content. The authors removed several common food intolerances (dairy, eggs and gluten) in addition to implementing a low carbohydrate diet.
Here’s the breakdown: 180 total participants 84 males and 96 females aged 30-45 years. All subjects tested negative for celiac disease (in truth the specific language they use is “all subjects did not present celiac disease” so I am uncertain if they actually tested them or not).
The experimental diet was followed for 3 weeks and included aiming for macro’s of carbs 12-15%, proteins 50-60%, and lipids 25-30%. Foods excluded: goitrogenic foods (unlisted specifically what these were), eggs, legumes, dairy, bread, pasta, fruits and rice. Control group followed a low calorie diet without restrictions on types of food to consume.
The author referenced goitrogenic foods repeatedly as part of the dietary exclusion but in the materials and methods section these foods were not specifically listed. In the introduction the author discusses goitrogenic foods and states “These substances (known as goitrogens) are found especially in products of the cruciferous (Brassicaceae) family (rape seed or canola, cabbage, turnip, watercress, arugula, radish, horseradish) and in milk produced by cattle nourished with these vegetables. Other goitrogens include soy, spinach, millet, tapioca, and lettuce. Even certain food additives, ie, nitrates used for fish and meat preservation, prevent iodine uptake by the thyroid gland.” So it’s unclear which foods were actually excluded in the experimental group. What is clear is this is not a simple low carb diet analysis.
The author also put a heavy emphasis on goitrogens and Hashimoto’s. I haven’t seen goitrogen’s make much of a difference clinically with Hashimoto’s patients. Check out this article written by Dr. Alan Christianson for a much deeper dive into goitrogens and Hashimoto’s.
Bottom line: don’t switch your diet just yet, we need more research on nutrition and Hashimoto’s. This study used too many dietary variables and was very short in duration.
Oxidative Stress and Hashimoto’s (2014)
This study is straightforward. The investigators compared biomarkers in people with euthyroid autoimmune thyroiditis (read: Hashimoto’s disease but normal levels of TSH, FT3, and FT4) and people without any thyroid disease. It was a small study with only 70 participants. I appreciate that they looked at a diverse set of biomarkers to assess oxidative stress including oxidized LDL. They controlled for variables that could impact oxidative status such as age, BMI, and fasting glucose. It is not surprising that folks with Hashimoto’s had a decrease in antioxidants and an increase in oxidants vs controls. We have a delicate balance of free radicals (oxidative stress) and antioxidants keeping our bodies healthy. If the scales tip and we are under higher levels of oxidative stress a whole host of disease can occur. Excessive levels of oxidative stress is considered one of the factors underlying the autoimmune response.
Bottomline: Folks with Hashimoto’s have lower levels of antioxidants and higher oxidative stress. It’s important to consume a diet rich in antioxidants.
- Ucan B, Sahin M, Sayki Arslan M, Colak Bozkurt N, Kizilgul M, Güngünes A, Cakal E, Ozbek M. Vitamin D Treatment in Patients with Hashimoto's Thyroiditis may Decrease the Development of Hypothyroidism. Int J Vitam Nutr Res. 2016 Feb;86(1-2):9-17. doi: 10.1024/0300-9831/a000269. Epub 2017 Jul 12. PMID: 28697689.
- Liu S, An Y, Cao B, Sun R, Ke J, Zhao D. The Composition of Gut Microbiota in Patients Bearing Hashimoto's Thyroiditis with Euthyroidism and Hypothyroidism. Int J Endocrinol. 2020 Nov 10;2020:5036959. doi: 10.1155/2020/5036959. PMID: 33224194; PMCID: PMC7673947.
- Muhittin Yalcin M, Eroglu Altoniova A, Cavnar B, Bolayir B, Akturk M, Arslan E, Ozkan C, Cakir N, Balos Toruner F. Is thyroid autoimmunity itself associated with psychological well-being in euthyroid Hashimoto’s thyroiditis? Endocrine Journal. 2017, 64(4), 425-429
- Esposito T, Lobaccaro JM, Esposito MG, Monda V, Messina A, Paolisso G, Varriale B, Monda M, Messina G. Effects of low-carbohydrate diet therapy in overweight subjects with autoimmune thyroiditis: possible synergism with ChREBP. Drug Des Devel Ther. 2016 Sep 14;10:2939-2946. doi: 10.2147/DDDT.S106440. PMID: 27695291; PMCID: PMC5028075.
- Baser, H., Can, U., Baser, S. et al. Assessment of oxidative status and its association with thyroid autoantibodies in patients with euthyroid autoimmune thyroiditis. Endocrine 48, 916–923 (2015). https://doi.org/10.1007/s12020-014-0399-3