Ginger and Thyroid Function: Everything You Need to Know

If you've heard ginger is good for thyroid function, tread gingerly. While the spice may have other health benefits according to traditional medicine — and won't hurt you in moderate quantities — claims of ginger's purported ability to boost thyroid health remains unsupported by science.

"I have not seen any well-documented, evidence-based proof to show that ginger — in any shape or form — is of any benefit in thyroid care," says Boston-based James Hennessey, MD, director of clinical endocrinology at Beth Israel Deaconess Medical Center.

That said, "I do know there are plenty of places that are trying to sell patients ginger for all kinds of things, including thyroid health," he says. "But the idea that there is some kind of confirmed relationship between ginger and thyroid health is certainly not common knowledge among thyroid specialists."

So why all the promising claims? Well, Dr. Hennessey says, "there is some animal research suggesting that ginger might have an impact on metabolism, and that it might have some anti-inflammatory effect — in theory."

And because — as the Cleveland Clinic notes — thyroiditis is an inflammation or swelling of the thyroid gland, Dr. Hennessey says "it's been extrapolated to suggest it could be good for addressing thyroid problems," he adds. "But these claims have not been rigorously evaluated by medical science."

The bottom line: Buyer beware. "Would I use ginger to treat, for example, subacute thyroiditis? The answer would be no," Dr. Hennessey says.

If you're worried ginger will interfere with levothyroxine, a medicine used to treat hypothyroidism, per the U.S. National Library of Medicine (NLM), you can rest easy.

There's no evidence eating or drinking ginger while taking levothyroxine will interfere with the treatment's therapeutic effect, Dr. Hennessey says.

"Taking ginger with levothyroxine is not mainstream thyroidology," he says. "But doing so doesn't appear to negatively impact this standard of care."

As for ginger's safety profile, Dr. Hennessey says a single case report suggests ginger supplementation could increase the risk for subacute thyroiditis (ST). (According to UCLA Health, ST is a rare inflammation of the thyroid gland thought to be the result of a viral infection.) "But that's just one case study," he says, "so it's hard to know if that's a real concern."

Meanwhile, according to the National Center for Complementary and Integrative Health (NCCIH), the spice — sourced from the underground stem of the ginger plant — does appear to be generally safe as an oral dietary supplement and a topical treatment. Ginger has been used as a traditional medicine for more than 2,500 years in China, and for roughly 500 years in both India and Japan, per the NCCIH.

Still, the NCCIH cautions the spice can trigger side effects, particularly large amounts of ginger, such as:

• Heartburn
• Diarrhea
• Discomfort in the abdominal region
• Irritation of the mouth and/or throat

There's no particular dietary treatment for hypothyroidism (when the thyroid doesn't produce enough hormone, according to the NLM), and no evidence of a connection between any food and improved thyroid function, per the Mayo Clinic.

Adequate iodine is essential to proper thyroid function, but iodine deficiency is not a concern in industrialized nations — and too much iodine intake can actually trigger hyperthyroidism, when an overactive thyroid generates excess thyroid hormone, according to the Endocrine Society.

Soy can interfere with thyroid hormone production, according to both the Mayo Clinic and the British Thyroid Foundation (BTF). In fact, the BTF specifically advises patients avoid soy while undergoing levothyroxine treatment.

Plus, kelp (derived from seaweed) can impede thyroid function, while iron tablets can block thyroid hormone absorption, per the BTF.