Your thyroid might be small, but it plays a huge role in your metabolism, energy levels, and overall well being.

Whether you’ve been diagnosed with a thyroid condition or you’re just looking to keep your hormones balanced, what you eat and drink matters, and that includes your daily cup of matcha. So, where does matcha green tea really stand when it comes to thyroid health? Let’s break it down and see.

How can matcha effect thyroid function?

Wondering if you can drink matcha if you have hypothyroidism? The short answer is yes, but you don't want to overdue it as high amounts of matcha may have an impact on your body's iodine absorption. 

While matcha green tea is loaded with antioxidants, amino acids, and natural compounds that may have positive effects on the health of your thyroid when used in moderation, we recommend you always consult your doctor before you begin a daily matcha regimen. 

What is your thyroid and what does it do?

Before we dive into matcha’s impact, let’s talk about what your thyroid actually does. This small but powerful gland is shaped like a butterfly and located at the base of your neck, it produces thyroid hormones (T3 and T4), which regulate:

• Metabolism - Controls how your body uses energy

• Heart Rate & Circulation - Influences heart function and blood flow

• Temperature Regulation - Keeps your body temperature balanced

• Mood & Brain Function - Affects focus, memory, and mental clarity

• Digestive Health - Plays a role in gut function and nutrient absorption

When your thyroid is functioning properly, you probably don’t think about it much. But when it’s underactive (hypothyroidism) or overactive (hyperthyroidism), symptoms like fatigue, weight fluctuations, brain fog, and mood changes can show up fast.

Explaining hypothyroidism 

Hypothyroidism occurs when the thyroid gland doesn’t produce enough thyroid hormones (T3 and T4), leading to a slower metabolism and a wide range of symptoms like fatigue, weight gain, cold intolerance, dry skin, and brain fog. 

It’s more common in women, especially those over 60, but it can also affect young people, particularly those with autoimmune disorders like Hashimoto’s thyroiditis, where the immune system attacks the thyroid by mistake.

At a scientific level, low thyroid hormone levels slow down the body's ability to convert food into energy, which is why your metabolism slows, and symptoms like low energy and weight gain occur. Hypothyroidism can be caused by iodine deficiency, autoimmune diseases, chronic stress, or even certain medications. 

Explaining hyperthyroidism

Hyperthyroidism is the opposite problem. The thyroid produces too much thyroid hormone, causing the metabolism to speed up. 

Symptoms include unexplained weight loss, rapid heartbeat, excessive sweating, anxiety, shaky hands, and difficulty sleeping. The most common cause is Graves’ disease, an autoimmune disorder that over-stimulates the thyroid. When the thyroid is overactive, the body enters a state of overdrive, burning energy too quickly. That can lead to muscle weakness, bone loss, and cardiovascular issues. 

Hyperthyroidism is more common in women and people with a family history of thyroid disorders. 

Matcha’s antioxidants may help reduce thyroid inflammation

Epigallocatechin gallate (EGCG), the main antioxidant in matcha, has been shown to reduce oxidative stress and inflammation, which are key triggers for autoimmune thyroid disorders like Hashimoto’s and Graves’ disease. Chronic inflammation can interfere with thyroid hormone production so adding anti-inflammatory foods and drinks like matcha can be helpful. 

Good for: People with Hashimoto’s thyroiditis (hypothyroidism) who need help reducing inflammation.

The connection between matcha, iodine, and hypothyroidism | An important connection to keep in mind

Iodine is crucial for thyroid function, your body needs it to make T3 and T4 hormones.

Some green teas (including matcha) contain small amounts of fluoride, which in very high doses may interfere with iodine absorption. But, unless you’re drinking excessive amounts of matcha daily (more than 5 cups), this is unlikely to be an issue especially if you get enough iodine from food sources like seaweed, fish, and iodized salt.

Matcha is a good choice for: People with balanced thyroid function who get enough iodine from their diet. 

Matcha may help regulate metabolism

A crowd favorite perk of matcha? It naturally supports a healthy metabolism.

Thanks to its caffeine and catechin content, matcha can help boost thermogenesis (calorie burning) and fat oxidation, which may be helpful for those dealing with slow metabolism from hypothyroidism.

However, if you have hyperthyroidism, excessive caffeine could intensify symptoms like rapid heart rate or jitteriness. If that’s the case, consider an alternative like decaf matcha. 

Good for: Individuals with hypothyroidism looking for a natural metabolism boost.

L-Theanine for reducing stress and cortisol levels

Chronic stress and high cortisol are known for interfering with thyroid hormone production and matcha contains L-theanine, an amino acid that promotes relaxation and reduces stress hormones.

Unlike coffee, which can spike cortisol (stress hormone) and trigger energy crashes, matcha provides a steady, sustained energy boost which is a big plus for people dealing with thyroid-related fatigue.

Good for: Anyone looking to reduce stress and support their adrenal-thyroid balance.

Caffeine & thyroid medication

If you take thyroid medication, caffeine may interfere with absorption if taken too soon after your dose.

It’s best to wait at least 30-60 minutes after taking your thyroid meds before drinking matcha to ensure proper absorption.

Good to know: If you’re sensitive to caffeine, decaf matcha is an option that still offers all the antioxidants without the stimulating effects! 

The bottom line

For most people, 1-2 cups of matcha per day is perfectly safe and beneficial for thyroid health! If you’re regularly drinking 4+ cups daily, especially without enough iodine in your diet, it may be worth cutting back or balancing your iodine intake to prevent any potentially negative side effects for your thyroid. 

If you have hypothyroidism or you are concerned about your iodine levels, it’s always a good idea to check with a doctor or nutritionist to make sure your matcha consumption is providing lots of benefits and no harmful interferences. 

Disclaimer: These statements in this blog post have not been evaluated by the Food and Drug Administration. The information provided here is for educational purposes only and should not be considered medical advice. It's essential to consult with a qualified healthcare professional before making any dietary or lifestyle changes. 

Resources:

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Peckham, S., Lowery, D., & Spencer, S. (2015). Are fluoride levels in drinking water associated with hypothyroidism prevalence in England? A large observational study of GP practice data and fluoride levels in drinking water. Journal of epidemiology and community health, 69(7), 619–624. https://doi.org/10.1136/jech-2014-204971

Lai, Y. W., & Huang, S. M. (2022). Tea consumption affects the absorption of levothyroxine. Frontiers in endocrinology, 13, 943775. https://doi.org/10.3389/fendo.2022.943775

Hetzel B. S. (1983). Iodine deficiency disorders (IDD) and their eradication. Lancet (London, England), 2(8359), 1126–1129. https://doi.org/10.1016/s0140-6736(83)90636-0

Michikawa, T., Inoue, M., Shimazu, T., Sasazuki, S., Iwasaki, M., Sawada, N., Yamaji, T., & Tsugane, S. (2011). Green tea and coffee consumption and its association with thyroid cancer risk: a population-based cohort study in Japan. Cancer causes & control : CCC, 22(7), 985–993. https://doi.org/10.1007/s10552-011-9771-2