Quercetin bad for thyroid It is high in antioxidants and plays an important role in combating free radicals, as well as reducing inflammation, allergy symptoms, and blood pressure. 2001;56(9):683-7. And Why It’s Bad for You. So regardless of what type of thyroid problem you have, it’s never a bad idea to lower inflammation in your body. I take 400 to 800mg/day and it doesn't adversely impact my thyroid function and I have hypothyroidism. Quercetin is used in various foods and as a dietary supplement as well. Jun 27, 2023 · Can quercetin affect thyroid? Introduction. Quercetin is an antioxidant found in many fruits and vegetables and belongs to a group of plant pigments called flavonoids. While getting the right nutrition is crucial, taking too much of some nutrients could impact – and even hinder, in some cases – proper thyroid function. Quercetin is present in many common foods, such as onions, grapes, apples, and berries. Quercetin is a plant flavonoid and has antioxidative properties. In the present study, we have evaluated the effects of quercetin on the expression of other thyroid-restricted genes, and we show that quercetin decreases the expression of the thyrotropin receptor, thyroid peroxidase and thyroglobulin genes. An attempt to evaluate the effect of quercetin at the promoter level of the thyroid-specific genes led to the observation that this compound induces the basal activity of the reporter vector. Just keep the dose reasonable, the anti-thyroid effects are very much dose-dependant (see link provided by u/Vauss88). The flavonoid quercetin regulates growth and gene expression in rat FRTL-5 thyroid cells. Quercetin has antioxidant and anti-inflammatory effects Apr 1, 2014 · In the present study, we further investigated the effects of quercetin on thyroid gene expression using FRTL-5 thyroid cells, which is a nontransformed thyroid cell line in continuous culture (Ambesi-Impiombato, 1986, Giuliani et al. In this study, we evaluated the therapeutic effect of quercetin on thyroid dysfunction in L-thyroxin (LT4)-induced hyperthyroidism rats. 5 after stopping so a bit lower but probably not statistically significant. Guardia T, Rotelli AE, Juarez AO, Pelzer LE. TSH was 4. The latter effect was associated with down-regulation of sodium/iodide symporter gene expression. Levothyroxine is in a class of medications called hormones. It is also used with surgery and radioactive iodine therapy to treat thyroid cancer. Atopic dermatitis is an autoimmune and inflammatory skin disease characterized by skin lesions exhibiting Quercetin is a plant pigment (flavonoid). We would like to show you a description here but the site won’t allow us. Quercetin is a natural pigment that can be found in many fruits and vegetables. Apr 17, 2020 · Quercetin is the most abundant flavonoid present in various types of vegetables, fruits, teas, wine, and many other food items. It's found in many plants and foods, such as red wine, onions, green tea, apples, and berries. Preliminary evidence suggests that a byproduct of quercetin can lead to a loss of protein function. Dec 15, 2022 · Why is quercetin bad for thyroid? Indeed, quercetin inhibits iodide organification through a thiourea-like action inhibiting thyroid peroxidase (TPO) enzyme activity and interferes with thyroid hormone metabolism, particularly through the inhibition of type I 5′-deiodinase activity [8]. 2 while taking quercetin and then 4. Quercetin can also improve the levels of endogenous antioxidants superoxide dismutase and catalase when they are depleted due to Mar 30, 2025 · See More Information Regarding Quercetin Levothyroxine Overview. 23 ± 1. Quercetin is the most consumed flavonoid present in fruits and vegetables. Did you know gluten could play hide and seek with your thyroid health? Jun 22, 2021 · Graves’ disease is the most common autoimmune thyroid disorder associated with hyperthyroidism. Effects of Quercetin on Thyroid Hormone Metabolism. Aug 23, 2024 · People with thyroid issues shouldn’t have more than an average daily recommended intake of 158 to 175 micrograms of kelp per day, Dr. Side effects may include headache and upset stomach. Consider natural histamines like quercetin. In a previous report, we showed that quercetin inhibits thyroid-cell growth and iodide uptake. Besides the effects on thyroid cells, quercetin also acts on thyroid hormone metabolism, inhibiting the enzyme deiodinases. Sources Graves’ disease is the most common autoimmune thyroid disorder associated with hyperthyroidism. Effects of rutin, quercetin, and hesperidin on adjuvant arthritis in rat. Quercetin is generally considered safe. The Role of Gluten in Thyroid Health. In vivo studies show that quercetin can decrease the rate of hepatic activation of T4 into T3 to a degree comparable to propylthiouracil. 7 (12-22) after stopping fir 8 weeks it had gone down to 13. For its antiproliferative, antiviral, anti-inflammatory and antioxidants activities, it is an active ingredient of several herbal remedies and is available as a nutraceutical. Free T3 was 4. Ensure you are not lacking in these, as anyone of them can be responsible for the symptoms of a sluggish thyroid. Experimental studies performed in vitro have demonstrated that quercetin inhibits growth and function in normal thyroid cells and may act as a May 14, 2023 · It’s interesting because while taking quercetin my Free T4 was 16. 5. 68 after stopping. 1-6. Endocrinology. The data raise the possibility that quercetin may be a novel disruptor of thyroid function, which has potential effects on, or use in, the therapy of thyroid diseases. Thyroid medications are goldilocks hormones — they need to be used in just the right dose — and there are risk factors of being overmedicated. Studies performed in vitro have shown that quercetin inhibits intrathyroidal 5′-deiodinase type 1 (D1), with an IC 50 of 13. More than 6,000 types of phytonutrients are found in this group. Farmaco. At the top of this list are quercetin, vitamin D, iron, and zinc. Anti-inflammatory properties of plant flavonoids. Let’s find out how quercetin works and if there are quercetin side effects on thyroid. Oct 4, 2024 · Indeed, quercetin inhibits the growth, the adhesion and the migration of thyroid cancer cells, and it also has redifferentiation properties in some thyroid cancer cell lines. Quercetin is a bioflavonoid common in the plant kingdom, a potent polyphenol antioxidant and immune system modulator. 8 (3. Keep reading to find out about how plant-derived flavonoids like quercetin 3. Apr 21, 2023 · For people struggling with common thyroid disorders, such as hypothyroidism or hyperthyroidism, nutrition plays an important role in maintaining overall health. 2008;149(1):84-92. In conclusion, these data suggest that, although its effects can be of benefit in hyperthyroidism and thyroid cancer, caution is required in the use of high doses of Nov 16, 2023 · According to some research, the standard kitchen staple onion shouldn't escape your attention either because it’s rich in quercetin—a flavonoid known to suppress thyroid hormone production. Feb 26, 2025 · Potential Benefits of Quercetin for Thyroid Health (and Overall Wellbeing) Given the lack of evidence linking quercetin to hypothyroidism, and its well-established antioxidant and anti-inflammatory properties, it's worth considering if quercetin might even offer any potential benefits for thyroid health, or at least for overall wellbeing in Mar 11, 2025 · Thyroid hormone is too powerful to just float around in your body so more than 99% of it is bound and unavailable for use by proteins like thyroid-binding globulin (8). Onions have the highest known quercetin content (200-600 mg/kg), with fruits in a close second with between 2 and 250 mg/kg. 51 μM . Therefore, the action of quercetin has been evaluated on the basal activity of several reporter vectors: The Mar 11, 2025 · And even if you can’t directly link inflammation to the onset of every thyroid disease, we can still say that inflammation is negative for thyroid function due to its effects on T4 to T3 conversion. . Atopic dermatitis is an autoimmune and inflammatory skin disease characterized by skin lesions exhibiting Aug 1, 2024 · Quercetin is the most abundant flavonoid present in fruits and vegetables. Levothyroxine is used to treat hypothyroidism (condition where the thyroid gland does not produce enough thyroid hormone). … Oct 6, 2023 · 8. Apr 15, 2017 · This summary of quercetin doesn't mention thyroid: Precautions. Several supplements can adversely impact the thyroid, like carnitine, and I notice in another comment that you supplement Mar 14, 2025 · Is quercetin bad for thyroid? However, concerns have been raised about the potential toxic effects of excessive intake of quercetin, and several studies have demonstrated that flavonoids, included quercetin, can interfere with thyroid function. When you increase estrogen, you increase thyroid-binding globulin, which reduces that 1% even further. This leaves a measly 1% of thyroid hormone available for your body to use. Apr 29, 2019 · Previous studies have shown that quercetin inhibits thyroid function both in vitro and in vivo. Mar 27, 2024 · I recommend testing thyroid hormone levels every six to 12 weeks while taking supplements, to ensure your thyroid medication dosage is optimized, or sooner, if you are showing any of the above symptoms. 8) while taking quercetin then 4. , 2006, Kohn and Valente, 1989). Quercetin can reportedly inhibit DNA damage by modulating oxidative stress in lymphocytes from Graves’ disease patients in vitro . LT4 was used to prepare the experimental hyperthyroidism model via the intraperitoneal injection. Veeramachaneni says. You should take periodic breaks from Dec 1, 2024 · It also has anti-allergy, anti-cancer, and brain-protective qualities. We show that quercetin down-regulates the expression of other thyroid-restricted Quercetin is a bioflavonoid first found in oak bark (Quercus alba). Apr 1, 2014 · In the present study, we further investigated the effects of quercetin on thyroid gene expression using FRTL-5 thyroid cells, which is a nontransformed thyroid cell line in continuous culture (Ambesi-Impiombato, 1986, Giuliani et al. Very high doses of quercetin may damage the kidneys. Jun 11, 2024 · Quercetin is generally safe when consumed in foods, but high doses as a supplement can cause health problems, including potential kidney damage and interactions with certain medications. wbv wrn rlg tzma ugmd wxh wkvbtw yqxanm txqxz zcz neszn jtify egz yufd gchw