How Myo-inositol Can Improve Hashimoto’s Symptoms

As an avid researcher, I am always struck by the interrelationship between diseases of the body and the mind. A good example of this that I often observe with Hashimoto’s clients is anxiety, mood swings, and OCD (obsessive-compulsive disorder) symptoms. I see these as clues that a person may be having underlying issues with their thyroid.

As a pharmacist, I’ve been frequently dismayed that our modern medical solution to these mind-body connections is to throw completely different prescription medications at the two. Not only does this often mean neglecting to “fix” the real root causes of both conditions, but many medications meant to address psychiatric symptoms often have unwanted side effects that make the physical health situation worse.

Looking for root causes is so important. I’ve seen many cases where people find out that something as relatively straightforward as a nutrient deficiency or a blood sugar imbalance, may be causing anxiety symptoms and exacerbating their thyroid condition.

The good news is that I’ve seen these people start to feel better pretty quickly once they have identified and addressed their root causes. For example, having people take therapeutic dosages of two nutrients, selenium and myo-inositol, in addition to working to balance their blood sugar, can work wonders at helping to promote relaxation and support normal emotional well-being, as well as maintaining healthy thyroid hormone levels and immune function.

Blood sugar imbalance can be a root cause of Hashimoto’s and anxiety, and is also a co-occurring symptom of another condition that affects many women, polycystic ovary syndrome (PCOS). Myo-inositol has been found to support healthy female hormone balance. It has also been found to support normal insulin sensitivity, which may contribute to female reproductive wellness and healthy fertility.

As you can see, myo-inositol can be greatly beneficial for those with Hashimoto’s!

In this article, you’ll discover:

• What myo-inositol is and how it supports our health
• How myo-inositol can improve Hashimoto’s symptoms
• The connection between PCOS, Hashimoto’s and blood sugar levels
• The connection between anxiety, depression, OCD, and Hashimoto’s
• Recommended dosage and precautions

What Myo-inositol Is and How It Supports Our Health

Myo-inositol is an important nutrient that serves key functions relating to hormone signal transduction throughout our endocrine system. As such, myo-inositol plays an important regulatory role relating to thyroid health (regulating the thyroid-stimulating hormone, or TSH) and reproductive health (regulating the follicle-stimulating hormone, or FSH). It also regulates glucose uptake and may be involved in serotonin uptake (our happy and calming hormone). ^[1]

Myo-inositol has been found to provide many valuable health effects, including anti-inflammatory, anti-oxidant, anti-diabetic, and anticancer effects. ^[2]

Research has shown that myo-inositol supplementation reduces thyroid antibody and TSH levels, as well as improves symptoms associated with anxiety, mood swings, depression, and OCD. ^[3] Research has also found that myo-inositol improves PCOS symptoms such as menstrual irregularities, acne, insulin resistance, and weight. ^[4] More will be discussed about each of these, further on in this article.

So what exactly is myo-inositol? And why might you be deficient in it?

Myo-inositol is a form of inositol, a type of natural sugar alcohol that’s present in mammalian cells. Inositol was previously known as vitamin B8, as it used to be thought of as an essential nutrient, but it was later learned that myo-inositol is actually made within our bodies, so it lost its “official” vitamin designation. However, just because we can make it internally, does not mean that we can’t be deficient in it! ^[5]

There are actually nine forms (referred to as isomers) of inositol, with the two most common being myo-inositol and D-chiro-inositol. These two forms are seen in much of the research relating to inositol, and in fact, they have been studied as a combination treatment relating to PCOS.

Myo-inositol is found in many plants and in the tissues of animals. Foods with the highest concentration of myo-inositol are fruits, beans, corn, and nuts. Blueberries, one of my favorite superfoods, are an especially rich source! ^[6]

Research has shown that although it is synthesized in the body, some individuals may not be able to meet their body’s metabolic needs through its own synthesis alone. ^[7]

While the human body (via the liver and kidneys) can produce up to 4 g/day of inositol, it has been found that the overly processed, high glucose (and low fiber) Western diets that many people follow, only provide about 1 g/day of the compound. ^[8]

People can be deficient due to their diet, poor nutrient absorption (common in Hashimoto’s), or perhaps even a genetic predisposition (such as having poor glucose metabolism). Additionally, consuming caffeine (coffee in particular) can increase one’s need for myo-inositol. ^[9] One study found that consuming myo-inositol powder alongside espresso reduced the absorption of the myo-inositol. ^[10]

High glucose levels hinder inositol availability by increasing its degradation and by inhibiting both myo-inositol biosynthesis and absorption.

How Myo-Inositol Can Improve Hashimoto’s Symptoms

Blood sugar imbalance is a potential root cause of Hashimoto’s, and I’ll talk more about that in the next section. But first, let me talk about the importance of myo-inositol relating to thyroid-stimulating hormone (TSH) signaling.

As I mentioned earlier, due to its key role in TSH signaling, myo-inositol supplementation has been shown to reduce thyroid antibodies, reduce TSH levels, and even achieve remission in people with Hashimoto’s. ^[11]

TSH signaling is a very complex process, and there are two different branches of signaling that have an impact on TSH levels. One of these branches is inositol-dependent, so too little inositol causes TSH resistance, resulting in too much TSH being produced. ^[12] Myo-inositol improves TSH sensitivity, which in turn results in a reduction of TSH levels.

Think of it this way. If someone has earplugs in their ears, they can’t hear well, so you have to yell for them to hear you. But if they remove the earplugs, they can hear you without you having to speak at a loud volume. The same concept applies to TSH. Without adequate myo-inositol, the body has to be “louder” and generate greater levels of TSH. In my first book, Hashimoto’s: The Root Cause, I discussed how an elevation of TSH, for whatever reason, may result in triggering or exacerbating the autoimmune process of Hashimoto’s. Providing myo-inositol in clinical studies appears to “remove the earplugs,” so to speak… resulting in less TSH being produced.

There have been a number of studies focused on myo-inositol relating to Hashimoto’s, PCOS, and OCD. Let’s first focus on Hashimoto’s.

Myo-Inositol and Selenium Work Synergistically to Support Optimal Thyroid Function

In most of the studies relating to Hashimoto’s, myo-inositol has been evaluated in conjunction with selenium, likely because the research has already proven selenium to be effective at reducing thyroid antibodies. ^[13] This is not surprising, as selenium deficiency is one of the most common nutrient deficiencies that I see in people with Hashimoto’s, and over 50 percent of them are likely deficient in it.

Selenium supplementation has been tied to a reduction in thyroid antibodies, improvements in thyroid symptoms, and a reduction in anxiety. ^[14] I routinely recommend that my clients and readers try selenium to see if it helps them feel better. You can read much more about selenium here.

Given selenium’s well-understood benefits for Hashimoto’s, studies have evaluated the incremental benefit of taking both selenium and myo-inositol over simply taking selenium alone.

And the findings have shown there are benefits to taking both. ^[15]

In one study done in 2013, patients with autoimmune thyroiditis were split into two groups, with one group being treated with 600 milligrams of myo-inositol and 83 mcg of selenium (selenomethionine) per day for six months, and the other being treated with just selenium. While both groups showed a decrease in thyroid antibodies, the group treated with myo-inositol also experienced a 31 percent reduction in TSH levels. The selenium group showed no change in TSH levels. ^[16]

The group taking the myo-inositol and selenium also showed a 44 percent reduction in thyroid antibodies, while the group taking selenium alone showed a 42 percent reduction in antibodies. Thyroglobulin was reduced by 48 percent with the myo-inositol/selenium combination, versus 38 percent with just selenium alone.

Some people actually went into remission after starting the myo-inositol. Improvements were seen in people’s assessment of their personal well-being. The authors of this study also pointed out that these two compounds were safe, with no side effects seen as part of their data collection.

In a more recent follow-up study in 2017, these results were confirmed and then expanded upon. Thyroid antibodies, TSH, and quality of life were all significantly improved after the administration of both myo-inositol and selenium. Interestingly, there was one case of hyperthyroidism included in this study, and in that single case, the supplementation increased TSH levels up to normal concentrations. ^[17]

My own clinical results also support the improvements that may be seen when taking myo-inositol with selenium. I recommend this combination as a first step for people with mild elevations in TSH and thyroid antibodies, and sometimes it’s just enough to do the trick. I often recommend using myo-inositol powder instead of using sweetener in tea!

The Connection Between PCOS, Hashimoto’s, and Blood Sugar

In at least one study, it was found that up to 50 percent of people with Hashimoto’s have an impaired tolerance to carbohydrates, causing issues with blood sugar imbalances and insulin surges. ^[18] I have found that many of my clients suffer from these types of surges, which can cause nervousness, anxiety, lightheadedness, and fatigue.

In a 2017 study on insulin resistance and Hashimoto’s, the authors concluded that high thyroid antibody levels are related to high fasting blood glucose levels and high insulin levels. Their findings indicated a possible relationship between insulin resistance, autoimmune thyroiditis, and TSH levels. They also concluded that patients testing with positive thyroid antibodies should be followed closely for diabetes mellitus and cardiovascular events. ^[19] (Learn more in my article about blood sugar imbalances and Hashimoto’s.)

Blood sugar and insulin resistance are also a problem commonly seen in women with PCOS. ^[20]

PCOS is an endocrine, reproductive and metabolic disorder, affecting at least 8 to 13 percent of reproductive-age women, worldwide. ^[21] Women with PCOS are found to have a 50 to 70 percent incidence of insulin resistance, independent of body size and build. In those who are obese, the prevalence of insulin resistance rises to 80 percent. ^[22]

Given these statistics, a common treatment for PCOS includes the insulin-sensitizing drug metformin. It has been shown to improve insulin sensitization and ovulatory function. ^[23] Metformin does, however, have a number of negative side effects.

Remember when I said myo-inositol is involved in hormone signal transduction and helps to regulate TSH, FSH, and glucose uptake? Well, due to its similar regulatory role relating to addressing glucose intolerance, myo-inositol has been identified as being a potential substitute for metformin in improving PCOS symptoms. Subsequently, research focused on this has confirmed the positive results of myo-inositol supplementation. ^[24]

Myo-inositol is the most abundant inositol form found within the ovary, with approximately 99 percent of the ovarian intracellular inositol being myo-inositol. (20) Studies have shown that a high concentration of myo-inositol is required to ensure healthy oocyte (immature egg) maturation in the ovary. ^[25]

So it is no wonder, then, that research has found myo-inositol to be beneficial for women with PCOS! One study found that after just 12 weeks of myo-inositol supplementation, there were improvements to insulin levels and LH/FSH levels, with both being significantly reduced. (These markers can be a potential signal of fertility challenges when elevated.) Menstrual cycles also normalized. ^[26]

Other studies have also shown that myo-inositol can help normalize menstrual cycles. A 2022 study on 50 women between the ages of 18 and 45 with PCOS, found that two grams per day of myo-inositol, for three months, resulted in reduced blood flow during periods (from 19.1 mL to 14.1 mL, which was statistically significant), a slightly increased length of periods (from 4.4 days to 4.7 days), and a major improvement in how heavy or normal menstrual flow felt. ^[27] Before treatment, only 14 percent of participants had a normal flow pattern, but this improved to 80 percent after treatment.

In another study, myo-inositol supplementation was found to improve the number of good quality oocytes, clinical pregnancies, and delivery rates in overweight women with PCOS. Insulin sensitivity improved as well. ^[28]

Additionally, there are many studies that have focused on the benefits of pairing myo-inositol and D-chiro-inositol to reduce insulin resistance and improve ovarian function in women with PCOS. ^[29]

In one of these studies, a myo-inositol and D-chiro-inositol combination therapy was found to improve oocyte quality, embryo quality, and pregnancy rates during in vitro fertilization. ^[30]

In another study, the combined myo-inositol and D-chiro-inositol treatment was found to be better than myo-inositol alone at improving ovulation, endocrine, and metabolic parameters. ^[31] An additional study showed a significant improvement in insulin sensitivity as well as lipid profile in PCOS patients. ^[32]

Besides metformin, myo-inositol is now considered a further insulin-sensitizing supplement that could benefit women with PCOS. Unlike metformin, which is known for numerous side effects, including lactic acidosis, a potentially serious side effect, myo-inositol was reported to be well tolerated (although I have seen reports of people feeling more tired after taking it).

There is also a connection seen between women with both PCOS and hypothyroidism. My theory is that this connection can be partly explained by shared root causes, such as both having blood sugar imbalances as well as having deficiencies in myo-inositol (resulting in a less-than-optimal inositol-dependent signaling pathway). In one study, it was found that 22.5 percent of women with PCOS also had hypothyroidism, compared to just 8.75 percent in controls. ^[33] The same authors also found TPO antibodies present in 27 percent of patients with PCOS, versus 8 percent in controls. More recently, a study found a higher prevalence of Hashimoto’s, higher antibody levels, and elevated TSH levels in PCOS patients. ^[34]

In light of its insulin-sensitizing activity, myo-inositol is used today to prevent and/or treat a number of metabolic disorders related to insulin resistance, such as metabolic syndrome, gestational diabetes mellitus, and PCOS.

The Connection Between Anxiety, Depression, OCD, and Hashimoto’s

Research has shown that anxiety, depression, mood fluctuations, OCD behaviors, and a general feeling of being “unwell,” are early signs of an autoimmune attack on the thyroid, and can be correlated to thyroid antibodies, even when the TSH level is still “normal.” ^[35]

Many new clients come to me after being prescribed anxiety and mood-related medications, including SSRIs (Selective Serotonin Reuptake Inhibitors), lithium, antipsychotics, dopamine, and benzodiazepines. They don’t feel well, and may have other thyroid symptoms, but in many cases, are still being told their TSH level is normal, so their thyroid is fine (oh, and “just keep taking those anxiety meds!”). Sometimes the term hypochondriac is thrown about. I’ve had way too many clients who were told they were bipolar, when in fact their thyroid was out of balance.

Yet, there is research that concludes with the recommendation that people presenting with these types of psychiatric symptoms be initially screened for underlying thyroid issues. ^[36]

Anxiety and mood disorders are very common thyroid symptoms. A study in 2004 found that there is an association between the presence of an anxiety or mood disorder, and the presence of TPO antibodies. ^[37] (You can read more about mood disorders and Hashimoto’s.)

The most common type of anxiety disorder reported in people with thyroid antibodies is obsessive-compulsive disorder (OCD). ^[38] I myself used to have issues relating to OCD (which interestingly is very common in pharmacists and those with Type A personalities, like yours truly!) and anxiety, which seemed to rear their ugly heads before I got my Hashimoto’s into remission, and when I have had flare-ups.

But, I have seen the positive effects of successful interventions, like removing reactive foods, reducing stress, and treating Streptococcal-based gut imbalances (which have been tied to OCD — and in my findings, also Hashimoto’s), as well as addressing various nutrient deficiencies. Two that I recommend most often relating to OCD, are selenium and myo-inositol.

Several studies have found that daily treatment with inositol resulted in improvements in OCD symptoms like anxiety and avoidant behavior (measured as a reduction on the Yale-Brown Obsessive-Compulsive Scale). ^[39]

In one small study, 13 patients with obsessive-compulsive disorder were given either 18 g of inositol or a placebo, daily, for 6 weeks. The subjects had significantly lower scores on the Yale-Brown Obsessive-Compulsive Scale when taking inositol. The authors concluded that inositol is effective for depression, panic, and obsessive-compulsive disorders, a spectrum of disorders responsive to selective serotonin reuptake inhibitors. ^[40]

Just like myo-inositol regulates TSH, FSH, and glucose uptake, research has shown that it may be involved in the modulation of serotonin uptake, too. ^[41] I think it is a much more natural solution to anxiety and OCD behaviors versus some of the psychiatric prescription medications that so many people are on today!

Along with anxiety and OCD, depression is also associated with Hashimoto’s.

In a meta-analysis comprised of 19 studies, with a total of 36,174 participants (34,094 for anxiety and 35,168 for depression), patients with AIT (autoimmune thyroiditis), subclinical hypothyroidism, or overt hypothyroidism had significantly higher scores on standardized depression and anxiety tests. The authors concluded that patients with AIT exhibit an increased chance of developing symptoms of depression and anxiety, or receiving a diagnosis of depression and anxiety disorders. ^[42]

The study found that approximately 23.8 percent of patients with AIT experience depression, and approximately 41.6 percent of patients with AIT experience anxiety disorders.

To learn more about depression and Hashimoto’s, please see my article.

It makes sense that mood swings, anxiety, OCD, and even depression can be so intertwined with Hashimoto’s. Fluctuating thyroid hormone levels (due to any number of root causes), adrenal stress, and even the autoimmune process itself (when your body is making antibodies that attack the thyroid), can be common culprits. The good news is there are a lot of interventions that can help, including addressing the nutrient deficiencies and blood sugar balancing issues we’ve been discussing.

One other strategy that I often discuss with clients having these types of anxiety and mood-related symptoms, is changing up their thyroid medication to a T3-containing medication like Nature-Throid, WP Thyroid, Armour, or compounded T4/T3. In my survey of Root Cause readers, around 60 percent reported improved mood after switching to a T3-containing medication.

Myo-Inositol for Medication Side Effects

Because of myo-inositol’s role in insulin signaling, hormonal regulation, and neurotransmitter modulation, some practitioners find it useful for addressing both metabolic and neurological side effects of medications.

More specifically, it may be helpful for medications commonly prescribed for depression, OCD, and anxiety such as antipsychotics, SSRIs, and mood stabilizers. It may also be useful for progrestin-based contraceptives, chemotherapy agents, and corticosteroids.

I am especially interested in using myo-inositol in people who experience lithium-induced thyroid disorders. Lithium is considered a mood stabilizer and is prescribed for bipolar disorder, depression, and schizoaffective disorder. Side effects of lithium may include tremors, weight gain, and polycystic ovary syndrome (PCOS)-like symptoms. It can also affect thyroid function. Also, myo-inositol deficiency may increase the risk of thyroid cancer. ^[43]

Lithium can reduce the amount of myo-inositol in cells, which may affect signaling within the cell. This has led to the “inositol-depletion hypothesis,” which suggests that lithium’s therapeutic effect on bipolar disorder is due to inositol depletion. However, some studies have found that lithium does not significantly change myo-inositol concentrations in the brain. ^[44] That said, it’s the myo-inositol in the body that causes a lot of the dysfunction.

Other research has found that low levels of inositol in the brain may contribute to mental health issues. One study found that people who committed suicide, and patients with bipolar disorders, had significantly lower levels of inositol in their frontal cortex, compared to those of the normal comparison group. ^[45]

Based on my experience and research, I believe that myo-inositol can play a therapeutic role for people who experience lithium-induced thyroid disorders, and may generally help people mitigate the side effects of lithium.

One small study found that supplementing with 4 grams of inositol daily was helpful in counteracting and preventing side effects of lithium. ^[46] The study followed 15 patients over the age of 18 who were taking lithium for six months. They monitored thyroid markers (free T3, free T4, and TSH) as well as metabolic markers such as fasting insulin, glucose, HOMA-IR index, triglycerides, HDL, and LDL. The study found that inositol treatment improved these lab values and did not interact with the pharmacological therapy, while at the same time preventing and counteracting potential side effects.

If you’re considering myo-inositol for managing medication side effects, it’s best to consult a healthcare provider to ensure proper usage and dosing.

Recommended Dosage and Precautions

Given the research and the results in my own clinical practice, I typically recommend that people with Hashimoto’s try supplements such as selenium and myo-inositol. Generally, you do not need to test your own levels of these nutrients. They have been shown to be safe (with noted precautions) in the research, so my philosophy is to try them and see if they result in improvements.

Rootcology offers two products that contain myo-inositol.

The first is Myo-Inositol Powder, which contains the myo-inositol form of inositol, studied for supporting healthy thyroid and immune function. ^[47] This powder can also help promote relaxation and restful sleep, as well as support balanced hormones. ^[48] For those looking to support healthy blood sugar levels, myo-inositol can be helpful in maintaining normal insulin sensitivity and carbohydrate metabolism.* ^[49] This form is great for anyone who doesn’t like taking pills or who wants to replace sugar or other sweeteners in their tea or coffee, as myo-inositol has half of the sweetness of table sugar and may just do the trick! I recommend taking 700 mg daily.

Here’s what Jan had to say after trying my Myo-Inositol Powder:

“I have just started using this product. Being unable to use most supplements due to extreme reactions and sensitivity, I was skeptical at first. However, I use it at a substantially reduced amount and have found it to be very helpful for my anxiety, irritability and overall mood.* Having Hashimotos has been a real struggle for me most of my life and conventional doctors have been unable to direct me in any way to help with this obstacle so I have felt unhinged for over 6 years. After reading the product information provided, I decided to give it a try and ‘hope for the best’. I am pleasantly surprised at the peacefulness that has returned to my body. Thank you for your product. I hope all continues to go well with my usage and that I can try some of your other recommendations. Thank you for being there when there was nowhere else to turn.”

And here are some anecdotes from my readers who have tried myo-inositol:

“I introduced it recently and it’s been the first thing to make a big dent in my antibodies. My doctor advised it following your recommendation, so thank you!

“I love inositol for calming anxiety. I have severe claustrophobia and I found a large dose of inositol before an mri is as effective as Ativan for calming the panic symptoms of claustrophobia. It doesn’t eliminate them, it just makes them manageable.”

“Took it to try and tame anxiety, found it got rid of my night sweats.”

The other recommendation is Selenium + Myo-Inositol. This brand new formulation contains myo-inositol plus selenium in the form of selenomethionine, which have been studied for their ability to work together to support optimal thyroid and immune function.

For anyone looking to support immune health, hormone balance, and metabolic health, in addition to their thyroid, this is a great option.* ^[50] I recommend taking one capsule per day. Each capsule contains 600 mg of myo-inositol and 83 mcg of selenium.

With Rootcology’s 30-day, 100% satisfaction guarantee, you have nothing to lose but your symptoms! If you are unsatisfied for any reason, you may return the product within 30 days for a full refund, minus shipping/handling fees.

Precautions

As always, I suggest you work with a good functional medicine practitioner and consult with him or her before trying these or any other supplements, especially if you are pregnant, breastfeeding, or have specific health conditions. In addition, if you are on psychiatric medications, please do not go off them without working with the prescribing practitioner.

Myo-Inositol and Lightheadedness

Myo-inositol can cause lightheadedness in some people. There are several possible reasons for this:

• Blood Sugar Lowering Effects: Because myo-inositol can improve insulin sensitivity and lower blood sugar, this can lead to reactive hypoglycemia in some sensitive individuals. This can cause dizziness, shakiness, and lightheadedness, especially if taken on an empty stomach or with other insulin-sensitizing agents (like berberine or metformin).
• Blood Pressure Modulation: Myo-inositol may have mild blood pressure–lowering effects by improving endothelial function. If your baseline blood pressure is already low (which is common in those with thyroid and adrenal issues), this can cause you to feel lightheaded or faint when standing up.
• Electrolyte Imbalance: Though less common, improved insulin signaling can shift potassium and other electrolytes into cells, which might subtly affect fluid balance and blood volume, again contributing to that “woozy” feeling.
• Adrenal or Thyroid Sensitivity: If you’re dealing with adrenal fatigue or hypothyroidism, your body may already be struggling with cortisol or blood pressure regulation. Myo-inositol may push your system toward imbalance, particularly if taken in high doses or combined with other calming nutrients like magnesium or GABA.

If you’re experiencing lightheadedness with myo-inositol, or know that you experience any of the above conditions that make you more prone to lightheadedness, you can start with a lower dose. Start at 250 mg per day and slowly increase your dose. If you do experience lightheadness, dial the dose back.

Take myo-inositol with food to help prevent blood sugar dips. You can use a continuous glucose monitor to track blood sugar levels, and if you experience low blood pressure, you may wish to use a blood pressure monitor.

If you’re on other glucose-lowering medications or supplements (like metformin or berberine), space them out from myo-inositol.

Consult your doctor before trying any new supplement, and if you experience any side effects such as lightheadedness.

Myo-Inositol/Selenium + Myo-Inositol

Myo-inositol may not be properly cleared when the kidneys are overworked, such as in kidney disease or while taking diuretics. As such, myo-inositol should not be taken by people who have kidney disease or who may already be taking supplements, such as cleavers (a diuretic herb), that can affect the kidneys or the lymphatic system.

Consult with a practitioner before use if you are pregnant or breastfeeding, or if you have a history of heavy bleeding. Some people have reported increased bleeding with the use of myo-inositol, so I would not recommend it with a history of heavy bleeding, or in those taking blood thinners. If you experience any of these effects, discontinue taking it.

Those with a corn allergy should not take Selenium + Myo-Inositol, and should consult with their practitioner before taking Myo-Inositol Powder. Myo-Inositol Powder contains an ingredient derived from non-GMO corn, but does not contain a detectable protein component which could cause an antigenic response, in the final product. While it is generally well-tolerated by those with corn sensitivities, please consult with your practitioner before use if you have a corn allergy or other individual concerns. Selenium + Myo-Inositol uses a non-GMO corn-derived ingredient and may contain a protein component that could cause an allergic response in those with corn allergies.

People with diabetes taking any form of myo-inositol should watch for signs of low blood sugar (hypoglycemia), as myo-inositol may lower blood sugar and hemoglobin A1c levels.

Do not take Myo-Inositol or Selenium + Myo-Inositol if you are taking the following medications: antidiabetic drugs, and/or blood thinners. Additionally, do not take Selenium + Myo-Inositol if you are taking anticoagulant/antiplatelet drugs, barbiturates, and/or immunosuppressants.

Rarely, myo-inositol has been associated with nausea, headaches, dizziness, or fatigue. If you experience these effects, discontinue taking it.

While research has shown that myo-inositol seems to have a normalizing effect on testosterone in women with PCOS, myo-inositol has been shown to increase testosterone in men with low levels of this hormone. Thus, myo-inositol can be used by both men and women. However, a word of caution for men who are sexually active: myo-inositol can increase sperm quality, leading to surprise pregnancies in partners of men who were previously thought to be infertile. ^[51]

Selenium

Though selenium side effects and toxicity are rare, doses in excess of 800 mcg per day can be toxic. The RDA for selenium has been defined as 55 mcg in the United States, and an upper limit of 400 mcg has been suggested. Selenium may also interact with other supplements and medications, such as cholesterol-lowering statin drugs, antacids, chemotherapy drugs, corticosteroids, niacin, and even birth control pills.

Those with a CBS gene mutation have difficulty breaking down selenium. If you know you have a CBS gene mutation, then regularly monitoring your selenium levels is necessary.

Selenium supplements are also associated with a risk of non-melanoma skin cancer (squamous cell carcinoma), so people at high risk of skin cancer should not take these supplements. In addition, there is possibly a link between selenium and prostate cancer, although data on this topic is conflicting.

Selenium intake may also cause side effects in those with diabetes.

Please review my selenium article to learn more about both benefits and precautions.

Monitoring Your Thyroid Hormones When Taking Myo-Inositol

Whenever you start a lifestyle or complementary intervention to address Hashimoto’s, I encourage you to work with your doctor to monitor your thyroid symptoms, thyroid hormones, and thyroid antibodies. This is a great idea for any lifestyle intervention, but a must for lifestyle changes that could impact your TSH, like myo-inositol, especially if you are already taking thyroid medications.

Myo-inositol can lower TSH by an average of 30 percent within six months, thus potentially reducing your requirement (or need) for thyroid meds. ^[52] So as you move forward with supplementation, please look out for the following symptoms of being overmedicated: rapid or irregular heartbeat, nervousness, irritability or mood swings, muscle weakness or tremors, diarrhea, heat intolerance, menstrual irregularities, hair loss, weight loss, insomnia, chest pain, and/or excessive sweating.

I recommend testing thyroid hormone levels every six to 12 weeks while using complementary therapies, to ensure your thyroid medication dosage is optimized, or sooner if you are showing any of the above symptoms.

Testing TSH, T4, T3, and the two most common Hashimoto’s antibodies, TPO and TG antibodies, is an important part of ensuring that the lifestyle changes you are making are both safe and helpful. 🙂 (You can read more about tests here.)

If your doctor is ordering these thyroid labs for you, be sure to request a copy so that you can see them for yourself and ensure that they are interpreted correctly. If you aren’t able to order through your physician, you may also wish to self-order your own thyroid monitoring labs. I recommend the Ulta Labs thyroid panel for monitoring your progress, which can be ordered anywhere in the U.S. (Some, but not all, insurance companies may reimburse you for self-ordered labs; please be sure to check with your plan.)

What You Can Do Today

People with Hashimoto’s are prone to nutrient deficiencies. (44) While it’s important to investigate and correct underlying root causes (such as food sensitivities, blood sugar imbalances, or gut issues), in the meantime, myo-inositol supplementation could help you feel better.

Remember, much of the research relating to Hashimoto’s has shown that myo-inositol can increase the effectiveness of selenium. Both have been found to reduce thyroid antibodies and anxiety. Myo-inositol has also been shown to reduce TSH levels and balance blood sugar, as well as help with depression, mood swings, and OCD. It can encourage a healthy mood, emotional wellness, and less stressful behaviors. ^[53]

For those with PCOS, myo-inositol may help to support a healthier reproductive system, as well as improve ovulatory function.

Even those who haven’t yet been diagnosed with thyroid disease, due to having a “normal” TSH level, could still have thyroid antibodies, and I recommend testing for those. It is easy and inexpensive, and antibody testing provides you with “early warning” information that can help you prevent further damage to your thyroid. Remember, you can have thyroid antibodies for years – even a decade – prior to testing abnormal for TSH.

I hope this helps you on your healing journey! Let me know how taking myo-inositol and selenium together works for you.

Looking for more info? Supplements can help or hurt your thyroid! Download my FREE eBook to learn about safe and effective supplements that can help your thyroid symptoms naturally.

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References

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^[13] Ibid
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^[23] Ibid
^[24]Ibid
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Note: Originally published in October 2018, this article has been revised and updated for accuracy and thoroughness.