The human intestine is colonized with bacteria. These good bacteria work together to digest foods, create vitamins and nutrients to be absorbable, regulate our immune system and communicate to the liver and the brain the state of health inside the body. These groups of bacteria are called the microbiome. The microbiome creates a unique environment that also regulates hormonal balance and effective detoxification.
The foods we eat shape the types of bacterias that live in the intestines. The westernized diet which is rich in calories, fats, meat and dairy proteins, high in salt and refined sugars, low in fiber, and highly processed is frequently associated with higher inflammation in the body, pre diabetes, diabetes, fatty liver, obesity, heart disease, hypertension, increased cancer risk, changes in immunity balance, oxidative stress, and altered intestinal bacterial flora.
The diet we have, therefore, becomes a risk factor for changes in our inflammatory status and autoimmunity. A result of changes in the balance and types of predominant bacteria in the gut and their subsequent actions affect our wellness.
Recent studies have linked, nutrition and alterations in the microbiome with various autoimmune diseases including rheumatoid arthritis, multiple sclerosis, psoriatic arthritis, celiac and inflammatory bowel disease, and possibly type one diabetes.
Increasing data also suggests that both thyroid autoimmune diseases, Hashimoto’s thyroiditis or Graves’ disease, may be related to gut microbiome bacterial imbalances and diet. For example patients with Hashimoto’s thyroiditis (thyroid inflammation and low thyroid function) report eating more animal foods and dairy products, and have different gut bacteria compared to controls. They have high firmicutes and low bacterioditis. This pattern is associated with weight gain due to greater prevalence of obesogenic bacteria that absorb more calories. These changes suggest that diet and gut bacteria either promote or fuel the immune response and or inflammation in Hashimoto’s thyroiditis. In contrast in Graves’ disease, a thyroid excess condition, you see a different ratio with low firmicutes and high bacterioditis. This ration promotes weight loss. There is also an over expression of a type of lactobacillus species that can cause trouble if they get in through the gut.
How does this happen? Well it turns out that having an inflamed or leaky gut can allow for these gut bacterias to enter into the blood. Parts of these bacterial can appear very similar to proteins that are present in the thyroid. Once these foreign bacterial antigen induce an immune response and bind freshly made antibodies, then these will go on to recognize thyroid proteins, by mimicry, and induce local inflammation in the thyroid and now this self attack begins the autoimmune process. The hypothesis is that thyroid imbalances or diet alter gut bacteria and gut bacterial imbalances induce inflammation, oxidative stress, and (self attack) autoimmunity causing a vicious cycle. These findings support the idea that gut health is crucial in preventing or addressing autoimmune diseases.
What can you do? My thoughts are the following. Have a more plants based diet, learn to rest the gut using intermittent fasting 12-16 hours first and then full day fasting. This helps your gut heal. Avoid foods that are inflammatory as described above. Rest more learn to deal with stress better. Make your gut health a priority.💕
Be Well, Dr. Beatriz
References:
1. Ruggeri RM et al. Influence of dietary habits on oxidative stress markers in Hashimoto’s Thyroiditis. Thyroid 31(1):96, 2021.
2. Shapiro F et al. Alterations of the gut microbiota in Hashimoto’s thyroiditis patients. Thyroid 28(2):175, 2018.
3. Jiang W et al. Gut microbiota may play a significant Role in the pathogenesis of Graves’ disease. Thyroid 31(5):810, 2021.