Does Glutathione Help Thyroid Health? Taking a Closer Look at the Possibilities of Supplementation

Disorders of the thyroid can wreak havoc on patients. With syndromes ranging from hyperthyroidism to Graves’ disease, problems with the thyroid can be difficult to identify and even harder to fix. For healthy people, the thyroid gets only minimal attention in general health habits, but for people with autoimmune diseases or genetic abnormalities, maintaining the peak performance of the thyroid can be an uphill battle that some don’t even know they’re fighting.

Without healthy regulation of thyroid hormones, the entire body can go suffer. These hormones are responsible for controlling bodily metabolism, which means that even minor deviations from the norm can impact body weight, energy levels, and mood. Given how many other bodily factors can cause these same symptoms, the thyroid may be the last place that patients think to look when they are not feeling well. Additionally, while a thyroid problem is usually easily diagnosed with a blood test, treatment can sometimes be difficult and disruptive. As such, patients will be better served by maintaining the health of their thyroid in the first place.

Unfortunately, patients have historically had few options for supporting their thyroid health on a routine basis. In recent years, however, researchers have wondered if glutathione supplementation may be a powerful tool for those who are seeking to maintain peak thyroid health. So does glutathione help thyroid health? Current evidence suggests that the answer is yes.

Glutathione’s Critical Role in Regulating Oxidative Stress

Glutathione is produced by nearly every cell in the human body and used by cells to regulate their level of oxidative stress, making it an essential part of maintaining health. Oxidative stress occurs when reactive oxygen species (ROS) chemically react with cellular machinery, preventing them from fulfilling their function. If left unaddressed, the oxidative stress that ROS cause can even kill cells. As such, controlling oxidative stress a cellular priority.

As a small molecule which is highly prone to reacting with ROS, glutathione is at the core of a handful of different oxidative stress management systems. In each of these systems, glutathione acts as a carrier of ROS; because the ROS are chemically bound to the glutathione molecule, they can’t react with cellular machinery to impair their function and cause damage. Glutathione is thus said to be an antioxidant. In addition to this antioxidant activity, glutathione also supports the other cellular antioxidant systems by offloading excess ROS from them and allowing them to be metabolized safely.

The Complex Relationship Between Glutathione and the Thyroid

Glutathione’s relationship with the functioning of the thyroid is indirect. While the majority of the body’s cells use glutathione to protect themselves from oxidative stress, different types of cells need slightly different quantities of glutathione. The cellular balance of glutathione is regulated via a handful of enzymes, one of which is glutathione peroxidase. These enzymes are upregulated or downregulated depending on cellular glutathione concentrations and exert a similar effect on glutathione itself. Glutathione peroxidase is of particular concern to the cells of the thyroid because oxidative stress can interfere with the thyroid’s primary job: producing hormones. Oxidative stress is controlled very tightly in the thyroid via synthesis of glutathione peroxidase, which can safely inactivate sources of oxidative stress like hydrogen peroxide and free radicals.

In the context of the thyroid, there’s one problem with synthesizing glutathione peroxidase in massive quantities: selenium insufficiency. Selenium is a necessary trace element that cells need because it’s a component of glutathione peroxidase and other glutathione system enzymes. Selenium is also an essential component of other metabolic systems for dealing with oxidative stress, such as the thioredoxin system. For most cells, access to selenium is easy because there are not very many enzymes which require selenium as a building block and synthesis of antioxidative stress enzymes and molecules proceeds unimpeded. In the thyroid, however, the story is different.

Thyroid cells require large amounts of selenium to synthesize the hormones which are then distributed throughout the body. If thyroid cells don’t have enough selenium, they can’t produce enough hormones for the body to maintain homeostasis and problems like Hashimoto’s disease develop. Additionally, other issues like liver disease may become aggravated further by fluctuating thyroid hormone levels even if the liver cells are capable of handling their own levels of oxidative stress.¹ Because thyroid cells uniquely use far more selenium than other cells, high levels of oxidative stress packs a double punch; when thyroid cells can’t synthesize enough glutathione peroxidase to reduce oxidative stress, they also end up without enough selenium to produce hormones. This leaves the cells incapable of doing their physiological job while also being incapable of repairing damage caused by oxidative stress. In the long term, excessive oxidative stress in the thyroid can cause thyroid cancer.² However, thyroid cells need to keep a small quantity of ROS on hand to incorporate into the thyroid enzymes that they produce.³ This means that thyroid cells need to maintain their level of oxidative stress within a certain range rather than uniformly attempting to lower it by producing more anti-ROS enzymes and molecules like glutathione.

So why don’t patients with compromised thyroids simply consume more foods containing selenium or take a selenium supplement? There are two reasons that make these avenues non-viable. First, selenium can be toxic if taken in excess. Though it is a necessary nutrient, the body has a relatively low rate of excess selenium excretion because evolutionarily selenium is a fairly uncommon nutrient to encounter. This allows selenium to build up and cause damage to the gut and other tissues because the body cannot easily store it. Second, selenium supplementation may not always result in higher glutathione peroxidase activity, though it does at least some of the time.⁴ The efficacy of selenium supplementation on glutathione peroxidase activity appears to be connected to the level of serum iodine; having an excess of iodine seems to nullify the impact of selenium. Clinically, this would lead to unpredictable results, with the day-to-day efficacy of the supplement varying wildly with the food consumed by the patient. The mechanisms responsible for these interactions are unclear, as is the utility for selenium supplementation for thyroid health.⁵Directly supplementing with glutathione may be a more appealing option.

How Does Glutathione Help Thyroid Health?

Glutathione supplementation can support thyroid health by reducing the need for selenium and providing the thyroid cells with an oxidative stress regulation tool which they natively use. Glutathione helps to recycle glutathione peroxidase, removing toxic products that the enzyme captures. This means that the thyroid cells will not need to produce extra glutathione peroxidase to cope with oxidative stress. Additionally, glutathione neutralizes ROS directly, independent of the antioxidant-enabling activity that it performs for glutathione peroxidase. Using a glutathione supplement would thus modify the threat model of thyroid issues from selenium insufficiency or excess oxidative stress. Rather than patients with compromised thyroids worrying about both impaired hormone production and thyroid damage, they would only need be mindful of maintaining a minimum viable level of oxidative stress to provision for essential functions (although it is highly unlikely that patients would be able to fully deprive their thyroid cells of the baseline level of oxidative stress that they need to produce hormones).

Using Glutathione to Optimize Well-being

While there is currently no data on the utility of glutathione supplementation in healthy individuals, the unique niche of the thyroid may well be where a glutathione supplement can do the most good for patients. For patients with a family history of thyroid disorders or who suspect that they have subjected their thyroid to excessive oxidative stress in particular, experimenting with high-quality glutathione supplements, such as those produced by Tesseract Medical Research, could potentially head off future issues while providing a boost of energy. However, by proactively supporting thyroid function, even patients without known risk factors may now have a new way of protecting their health and enhancing their quality of life.

Works Cited

1. Moustafa AHA, Ali EMM, Mohamed TM, Abdou HI. 2009. Oxidative stress and thyroid hormones in patients with liver diseases. European Journal of Internal Medicine. 20(7):703-708. https://www.sciencedirect.com/science/article/pii/S0953620509001605
2. Xing, M. 2012. Oxidative stress: a new risk factor for thyroid cancer. Endocrine-Related Cancer. 19(1):C7-C11. https://erc.bioscientifica.com/view/journals/erc/19/1/C7.xml
3. Poncin S, Gerard AC, Boucquey M, Senou M, Calderon PB, et al. 2008. Oxidative stress in the thyroid gland: from harmlessness to hazard depending on the iodine content. Endocrinology. 149(1):424-433. https://academic.oup.com/endo/article/149/1/424/2455161
4. Aghwan ZA, Sazili AQ, Alimon AR, Goh YM, and Hilmi M. 2013. Blood hematology, serum thyroid hormones and glutathione peroxidase status in kacang goats fed inorganic iodine and selenium supplemented diets. Asian-Australasian Journal of Animal Sciences. 26(11):1577-1582. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4093820/#__ffn_sectitle
5. Schomburg L, Kohrle J. 2008. On the importance of selenium and iodine metabolism for thyroid hormone biosynthesis and human health. Molecular Nutrition and Food Research. 52(11):1235-1246. https://onlinelibrary.wiley.com/doi/abs/10.1002/mnfr.200700465