Expert Advice

Gut Health & The Connection to Hypothyroidism

Acella Pharmaceuticals, LLC., is partnering with Lindy Ford, RD, LDN, to bring greater awareness to the importance of thyroid care and education. This post is sponsored by Acella Pharmaceuticals and should not be construed as medical advice. Please talk to your doctor about your individual medical situation.

Disclaimer: The information provided is for educational purposes only and does not substitute professional medical advice. Consult a medical professional or healthcare provider before beginning any exercise, fitness, diet, or nutrition routine.

Most of us know that Hashimoto’s thyroiditis and hypothyroidism are associated with symptoms such as fatigue, thinning hair, hormonal imbalances, depression, anxiety and weight gain. What many don’t know is that thyroid problems are also associated with the gut (or what I like to call the microbiome) and digestive issues.

This relationship between thyroid and gut health is often overlooked or misdiagnosed. It’s important to understand the gut-thyroid connection so we can advocate for ourselves more effectively.

Thyroid hormones play a key role in how well we assimilate, digest and absorb our nutrients from food. Just about every day, I say to someone in my practice, "You're not what you eat. You're what you absorb."

Thyroid dysfunction can lead to gastrointestinal symptoms such as bloating, pain, diarrhea, constipation and other digestive complaints associated with irritable bowel syndrome, or IBS. This scenario goes both ways – microbiome imbalances can also have a profound effect on the thyroid.

Not all those who suffer with thyroid disease present with symptoms. A low functioning thyroid will still have an effect on optimal digestion and absorption.

How the Microbiome Affects Thyroid Disease

Many patients with thyroid disease present with Hashimoto’s thyroiditis. All autoimmune diseases have a strong association to gut health issues. Hashimoto’s sufferers are five times more likely to present with celiac disease.1

Part of the problem with thyroid disease and gut health dysfunction can be explained by intestinal permeability, or "leaky gut." What is leaky gut? The small intestine has a barrier of tight junctures that allow for the absorption of nutrients from the food we eat. At the same time, this intestinal barrier protects against entry of parasites, bacteria, fungi and other allergens. It plays the role of "gate keeper."

When these allergens pass through easily, they can trigger autoimmune diseases in susceptible individuals.2 Leaky gut also makes key nutrient absorption less effective. Nutrients such as selenium, zinc, potassium, iron, iodine, vitamin A and B vitamins are essential to healthy thyroid functioning. They are deficient in those with thyroid dysfunction.

The "good" bacteria in our microbiome also play a part. These healthy bacteria influence the conversion of the storage hormone T4 into the active form, T3.2

There is more to it than this, but being able to absorb key thyroid nutrients is key.

How the Thyroid Affects Digestion & the Microbiome

Digestion begins with enzymes in your mouth. Studies reveal that people with Hashimoto’s thyroiditis often lack adequate amounts of saliva to start the breakdown of food.3

Thyroid dysfunction is also linked to low production of stomach acid; small intestinal bowel overgrowth, or SIBO; slow gastrointestinal movement and atrophic gastritis.4

Steps to Enjoying a Healthy Gut and Digestion with Thyroid Disease

1. Take the right medication. Talk to your healthcare practitioner about this and which options are right for you. I present with Hashimoto’s thyroiditis and take NP Thyroid®. I prefer a natural porcine medication because it contains the full spectrum of the thyroid hormone: T3 and T4.5 Plus, I find that NP Thyroid® is most like our natural thyroid hormones. For full Prescribing Information, including BOXED WARNING, please click here or scroll down to see Important Risk Information.

2. Get on a gut healing protocol. Find a health practitioner who has a proven track record of first healing leaky gut and then maintaining a healthy microbiome. When I work with a patient suffering from gut issues, I put them on a protocol that starts with the focus on healing leaky gut. It consists of targeted amino acids, digestive enzymes with HCL and a specific probiotic for their unique condition.

3. Consume gut healing foods on a regular basis. Yes, this consists of probiotic rich foods such as sauerkraut, kefir and other fermented foods, but don’t forget the prebiotic rich foods. Prebiotic fibers feed the good bacteria in our guts. When you add prebiotics, the good bacteria multiply and proliferate significantly faster. Prebiotic foods include onions, garlic, asparagus, jicama, chicory, dark greens, artichoke and many more foods.

For more information about healing foods and incorporating probiotic and prebiotic foods into your diet, then check out the video below on my YouTube channel.

Foods for a Healthy Gut for Weight Loss, Immunity & Better Mood

Gut Health and the Connection to Hypothyroidism

REFERENCES: 1. Wentz, Izabella. Hashimoto’s Thyroiditis: Lifestyle Interventions for Finding and Treating Root Cause. 2013. 2. Knezevic, J., Starchl, C., Tmava Berisha, A., & Amrein, K. (2020). Thyroid-Gut-Axis: How Does the Microbiota Influence Thyroid Function?. Nutrients, 12(6), 1769. 3. Jung, Jh., Lee, CH., Son, S.H. et al. High Prevalence of Thyroid Disease and Role of Salivary Gland Scintigraphy in Patients with Xerostomia. Nucl Med Mol Imaging. 51, 169–177 (2017). 4. Centanni M, Marignani M, Gargano L, et al. Atrophic Body Gastritis in Patients With Autoimmune Thyroid Disease: An Underdiagnosed Association. Arch Intern Med. 1999;159(15):1726–1730. doi:10.1001/archinte.159.15.1726. 5. NP Thyroid® Prescribing Information. Acella Pharmaceuticals, LLC. 2019.


Important Risk Information

Drugs with thyroid hormone activity, alone or together with other therapeutic agents, have been used for the treatment of obesity. In euthyroid patients, doses within the range of daily hormonal requirements are ineffective for weight reduction. Larger doses may produce serious or even life-threatening manifestations of toxicity, particularly when given in association with sympathomimetic amines such as those used for their anorectic effects.
  • NP Thyroid® is contraindicated in patients with uncorrected adrenal insufficiency, untreated thyrotoxicosis, and hypersensitivity to any component of the product.
  • In the elderly and in patients with cardiovascular disease, NP Thyroid® should be used with greater caution than younger patients or those without cardiovascular disease.
  • Use of NP Thyroid® in patients with diabetes mellitus or adrenal cortical insufficiency may worsen the intensity of their symptoms.
  • The therapy of myxedema coma requires simultaneous administration of glucocorticoids.
  • Concomitant use of NP Thyroid® with oral anticoagulants alters the sensitivity of oral anticoagulants. Prothrombin time should be closely monitored in thyroid-treated patients on oral anticoagulants.
  • In infants, excessive doses of NP Thyroid® may produce craniosynostosis.
  • Partial loss of hair may be experienced by children in the first few months of therapy but is usually transient.
  • Adverse reactions associated with NP Thyroid® therapy are primarily those of hyperthyroidism due to therapeutic overdosage.
  • Many drugs and some laboratory tests may alter the therapeutic response to NP Thyroid®. In addition, thyroid hormones and thyroid status have varied effects on the pharmacokinetics and actions of other drugs. Administer at least 4 hours before or after drugs that are known to interfere with absorption. Evaluate the need for dose adjustments when regularly administering within one hour of certain foods that may affect absorption.
  • NP Thyroid® should not be discontinued during pregnancy, and hypothyroidism diagnosed during pregnancy should be promptly treated.


NP Thyroid® (thyroid tablets, USP) is a prescription medicine that is used to treat a condition called hypothyroidism from any cause, except for cases of temporary hypothyroidism, which is usually associated with an inflammation of the thyroid (thyroiditis). It is meant to replace or supplement a hormone that is usually made by your thyroid gland.

NP Thyroid® is also used in the treatment and prevention of normal functioning thyroid goiters, such as thyroid nodules, Hashimoto’s thyroiditis, multinodular goiter, and in the management of thyroid cancer.