How Does Ashwagandha Affect the Thyroid for Hypothyroidism and Hyperthyroidism?

Medically Reviewed on 1/31/2023

What is ashwagandha? 

Ashwagandha is an ancient medicinal herb that has recently become popular as an alternative therapy for various conditions, like thyroid disorders. Read on to find out everything you need to know about the health benefits of ashwagandha for hyperthyroidism, hypothyroidism, and more.

Ashwagandha, scientifically known as Withania somnifera, is also called Indian ginseng or winter cherry. It’s a short shrub with small yellow flowers. This plant is native to India and Southeast Asia.

Ashwagandha gets its name from Sanskrit, an ancient Indian language. In Sanskrit, ashwagandha means “smell of the horse,” in reference to this herb’s distinct scent and ability to boost stamina.

It’s one of the most important herbs used in the traditional Indian medical discipline of Ayurveda. Ayurveda is based on the principles of natural healing. Since ancient times, ashwagandha has been used to combat aging, relieve stress and anxiety, build muscle, improve concentration, increase energy levels, boost immunity and fertility, and treat illnesses like rheumatoid arthritis and neurological disorders.

Currently, modern science is exploring the effects of ashwagandha on thyroid disorders.

What are the types of thyroid disorders? 

Your thyroid gland is located at the base of your neck. It’s a butterfly-shaped glandular organ that secretes the thyroid hormone in two forms — triiodothyronine (T3) and thyroxine (T4). This hormone plays an important role in regulating many bodily functions, like growth, development, and metabolism.

Thyroid hormone secretion is controlled by a peanut-sized gland located beneath your brain called the pituitary gland. The pituitary gland produces a substance called the thyroid-stimulating hormone (TSH). The main job of this hormone is to stimulate the thyroid gland to give out T3 and T4. 

If the T3 and T4 levels in your body drop, your pituitary gland will secrete more TSH to inform the thyroid gland that it needs to produce more hormones. However, an imbalance in the levels of these hormones can be an indicator of thyroid disease or poor thyroid health. 

Thyroid disorders are of two main types:

1. Hypothyroidism

This condition occurs when thyroid hormone levels fall below normal due to the thyroid’s gland inability to produce sufficient hormones. The main symptoms of hypothyroidism include fatigue, weight gain, dry skin, constipation, and goiter (swelling in the neck caused by an enlarged thyroid gland).

Hypothyroidism can happen due to a variety of factors. But the most common causes include iodine deficiency, side effects of certain medications, and autoimmune disorders like Hashimoto’s thyroiditis, in which your immune cells damage your healthy thyroid tissue.

According to statistical data, around 1% to 2% of people experience hypothyroidism in Western countries.

2. Hyperthyroidism

This condition occurs when thyroid hormone levels are higher than normal due to excessive stimulation and activity of the thyroid gland. The main symptoms of hyperthyroidism include arrhythmia (an irregular heartbeat), unintentional weight loss, fatigue, shortness of breath, and hair loss.

Hyperthyroidism can happen for multiple reasons. The most common causes include inflammation of the thyroid gland (thyroiditis), thyroid nodules, excess consumption of iodine, side effects of certain iodine-containing medications like amiodarone, and autoimmune disorders like Graves’ disease.

According to statistical data, around 0.2% to 1.3% of people experience hypothyroidism in Western countries.

The treatments for both hypothyroidism and hyperthyroidism involve drug therapy. But some herbal remedies like ashwagandha have been used in traditional medicine.  

What is the impact of ashwagandha on thyroid health?

Research has identified many potential health benefits of ashwagandha, including some beneficial effects on the thyroid gland.

Ashwagandha’s role in hypothyroidism

When you’re stressed, the cortisol (stress hormone) levels in your body increase. Cortisol suppresses thyroid function and causes T3/T4 levels to fall. 

Ashwagandha has endocrine-stimulating properties. It can suppress cortisol levels and boost thyroid function.

In an eight-week study of 50 people with hypothyroidism, the participants were given 600 milligrams of ashwagandha root extract daily. These people showed a significant improvement in thyroid hormone levels compared with people who didn’t receive ashwagandha. Their TSH levels increased by 17.5%, where T3 and T4 levels increased by 41.5% and 19.6%, respectively. 

In another study of people with bipolar disorder who were given ashwagandha, three people showed an increase in T4 levels.

Additional large-scale research in human populations is necessary to confirm these findings.

Ashwagandha’s role in hyperthyroidism

The effects of ashwagandha supplements on hyperthyroidism have yet to be studied. But the thyroid hormone production-boosting effects of ashwagandha have been well-documented in studies on hypothyroidism.

So, in people with existing hyperthyroidism, taking ashwagandha may boost T3/T4 levels to dangerous levels. This serious state of hyperthyroidism is called thyrotoxicosis.

Thyrotoxicosis is characterized by extremely high levels of circulating T3/T4 but low levels of TSH. Its symptoms include extreme thirst, weight loss, skin problems, and heart failure if left untreated.

Therefore, consuming ashwagandha might not be advisable for people with hyperthyroidism and requires adequate medical supervision.

What are the potential side effects of ashwagandha? 

Ashwagandha is generally considered safe for most people. But it’s not recommended for women who are pregnant or breastfeeding. Because of its thyroid-stimulating effects, it’s also unsuitable for people with preexisting hyperthyroidism.

Research shows that ashwagandha may influence the activity of sedatives and medications for certain conditions like hypothyroidism, high blood pressure (hypertension), diabetes, and psychoactive disorders.

In addition, ashwagandha has immune-stimulating properties. This means it can interfere with the action of immunosuppressive drugs and also worsen autoimmune conditions like lupus, rheumatoid arthritis, and multiple sclerosis.

People with these conditions need to be cautious and seek medical advice before taking ashwagandha.


According to the USDA, there is no difference between a “portion” and a “serving.” See Answer

How is ashwagandha used? 

Ashwangandha is commercially available in supplement form, usually as 300-mg tablets. You can take these two times a day after meals.

Ashwagandha is also sold in powder form. You can add this powder to water or beverages like milk, smoothies, and juices. You could also mix it with yogurt or sprinkle it on food items. Ashwagandha can be brewed into tea. 

Most studies on ashwagandha have used it in tablet form. Therefore, its effectiveness in powder and tea forms has yet to be established.

Human data on ashwagandha toxicity is also lacking. Unless otherwise specified by your health care provider, you should follow the manufacturing label’s instructions for consuming ashwagandha. 

The effects of ashwagandha may take time to appear. So, expect to wait for several months before observing any noticeable improvements. Consult your health care practitioner immediately if you get any side effects after taking these supplements

Medically Reviewed on 1/31/2023

Alternative Medicine Review: "Scientific basis for the therapeutic use of Withania somnifera (ashwagandha): a review."

BJOG: "Herbal medicinal products during pregnancy: are they safe?"

Endocrine: "Association between thyroid function and serum cortisol in cortisol-producing adenoma patients."

Institute for Quality and Efficiency in Health Care: "How does the thyroid gland work?"

Journal of Alternative and Complementary Medicine: "Efficacy and Safety of Ashwagandha Root Extract in Subclinical Hypothyroid Patients: A Double-Blind, Randomized Placebo-Controlled Trial."

Journal of Ayurveda and Integrative Medicine: "Exploratory study to evaluate tolerability, safety, and activity of Ashwagandha (Withania somnifera) in healthy volunteers," "Subtle changes in thyroid indices during a placebo-controlled study of an extract of Withania somnifera in persons with bipolar disorder."

Journal of Ethnopharmacology: "Safety and clinical effectiveness of Withania Somnifera (Linn.) Dunal root in human ailments."

Lancet: "Hyperthyroidism," "Hypothyroidism" "Thyrotoxicosis."

PloS One: "Triethylene glycol, an active component of Ashwagandha (Withania somnifera) leaves, is responsible for sleep induction."