Thyroid Conditions
Ingredient-specific thyroid cautions for adaptogens. Ashwagandha has NIH warnings and small trial results; for other adaptogens, thyroid evidence was not found in the sources we read.
Content last updated . This page has not been medically reviewed.
Safety first. Supplements can cause side effects and interact with medicines. Read mushroom safety and interactions before you use any mushroom product.
Do adaptogens affect the thyroid? For one ingredient, ashwagandha, health sources raise a thyroid caution and small human studies have measured thyroid blood tests. For the other adaptogens we checked, we did not find thyroid-specific statements. This page keeps those two groups apart. It is information, not a reason to start or stop any thyroid medicine: ask the prescriber or pharmacist.
Ashwagandha (Withania somnifera)
What official summaries say. NIH's NCCIH says ashwagandha is not recommended for people with thyroid disorders and might interact with thyroid hormone medicines. [1] Memorial Sloan Kettering (MSK) lists case reports of thyrotoxicosis (too much thyroid hormone) associated with ashwagandha supplements, with symptoms that resolved in all reported cases after the supplement was stopped. [2] It also lists that ashwagandha may increase thyroxine levels. [2] Case reports show an association in individual people. They do not show how often this happens.What small trials found. Results differ by population and are about blood tests, not proof of benefit or harm.
| Study | Who and how long | What was measured | Result as reported |
|---|---|---|---|
| Pilot randomized trial, India, 2018 [3] | 50 adults with raised TSH (subclinical hypothyroidism), 8 weeks, root extract vs starch placebo | TSH, T3, T4 | Authors reported improved values vs placebo and said it "may be beneficial" for normalizing thyroid indices. Single center, small. |
| Randomized safety study, India, 2021 [4] | 80 healthy adults, 8 weeks | Safety blood tests including thyroid profile | No statistically significant change in thyroid hormonal profile. |
Evidence label: mixed and limited. A blood-test change in a small trial is a biomarker result. The two trials used particular root extracts, and results do not transfer to other products or to leaf or whole-plant forms. NIH says ashwagandha may be safe up to 3 months, with insufficient information on long-term safety. [1]
Why the caution matters. Because MSK lists that it may increase thyroxine levels, [2] a supplement could change how a thyroid test is read. People with a thyroid condition or on thyroid medicine should ask their clinician or pharmacist before using it. More detail: ashwagandha and the thyroid.
Other adaptogens
Proper evidence not found in the sources we read for thyroid effects of rhodiola, ginseng species, eleuthero, schisandra, astragalus, licorice or maca. We searched NCCIH, MSK summaries, EMA monographs and LactMed. For maca, MSK only notes interference with testosterone lab tests. [5] "Thyroid support" or "hormone balance" on a label is a marketing claim here, not an established finding: see adaptogens for thyroid and hormone balance claims.Thyroid symptoms need a medical check
Tiredness, weight change and mood change have many causes, and no supplement can sort them out. See thyroid problems and fatigue and adrenal fatigue claims.Practical steps
- Tell your thyroid clinician about every supplement, including blends.
- Mention supplements before thyroid blood tests are interpreted.
- Do not change thyroid medicine on your own.
- Check the safety overview and medicine interactions.
Frequently asked questions
Does ashwagandha affect thyroid hormones?
Possibly. NIH advises against it with thyroid disorders and names thyroid medicines. [1] Small trials show mixed blood-test results. [3][4]
Can ashwagandha treat hypothyroidism?
No. One 50-person pilot reported improved test values, but that is not proof of treatment, and NIH does not recommend it with thyroid disorders. [3][1]
Can I take it with levothyroxine?
Ask your prescriber or pharmacist. NIH names thyroid hormone medicines among possible interactions. [1]
Do other adaptogens affect the thyroid?
Proper evidence not found in the sources we read.
Are "thyroid support" blends safe?
Labels and contents may differ, and blends mix ingredients. [6] Ask a clinician before using one.