Do I get the same awesome vitamin packs every time?

Yes! Well, unless you tell us to change it. We are going to send you the same personalized vitamin packs every month so that you don't miss a beat with your routine. But we also realize people's needs change; feel free to change, pause, or cancel your vitamin packs at any time for no charge.

Where should I store my vitamin packs?

Place them somewhere you can easily see them! We will send you your vitamin packs in an awesome dispenser box that you can place anywhere in your house. Make it visible so you remember to grab a pack every day.

How often do I receive my vitamin packs?

We will send you a new box every 28 days. However, if you need more time before your next shipment, you can always skip a month or delay the next order. We will email you a reminder before every shipment.

Are there any hidden fees you're not telling me about yet?

Nope, what you see in the checkout is what you will be charged. There are no cancelation fees of any type.

I already know what supplements I want. Do I have to take the quiz?

If you already know what you want, just browse our collection and add individual products to your cart. When you check out, those will be combined into one pack. Start by clicking the "Shop" button on the header of this page.

Last update: January 16, 2025

6 minute read

Selenium Deficiency

Could a lack of selenium be behind your thyroid troubles? Dive into how this essential mineral affects your thyroid health.

By Stephanie Wright, RN, BSN

Edited by Dr. Dimitar Marinov, MD, RDN, PhD

Learn more about our editorial standards

Ever wonder why your thyroid isn't functioning quite right? If your doctors have excluded other reasons, it might be time to consider selenium. This essential trace element is a powerhouse when it comes to thyroid health. But how exactly does it impact your thyroid, and could a deficiency be causing thyroid problems?

Key takeaways

Selenium is crucial for thyroid function, playing a key role in hormone production and conversion
Adequate selenium intake may reduce thyroid antibodies, potentially improving thyroid health
Foods rich in selenium include Brazil nuts, seafood, and organ meats, which may help boost levels

The importance of selenium for thyroid function

Selenium isn't just another mineral; it's a game-changer for your thyroid. It plays a pivotal role in producing selenoproteins, which are essential for antioxidant defense and regulating thyroid hormone synthesis. In fact, your thyroid gland contains more selenium per gram than any other organ in your body.

Selenium and thyroid diseases

Some studies suggest that low selenium levels may be linked to thyroid conditions like Hashimoto’s thyroiditis (HT) and Graves’ disease (GD). For example, a few clinical trials show that taking around 200 μg of selenium daily for three to six months can reduce thyroid peroxidase antibody (TPOAb) levels in people with HT.

However, not all research agrees—many studies are small or only track changes for a few months. Also, the clinical significance of these small improvements is unknown:

For HT, selenium might offer modest improvements in TPOAb, but its effect on overall thyroid function isn’t clearly proven. Plus, we don’t know whether these short-term benefits last beyond six or twelve months.
In GD, the data are even more preliminary. Some researchers think selenium could help reduce inflammation or oxidative stress, but we still don’t know if that makes a real difference in the long run. Larger, longer studies are needed to see if selenium truly helps people with GD.

The bottom line? While selenium may lower certain immune markers in some cases, its broader impact and long-term safety aren’t fully understood yet. If you’re considering selenium supplements—especially higher doses—be sure to consult a healthcare professional first.

Epidemiological evidence

Epidemiological studies offer compelling evidence of selenium's impact on thyroid health. In China, researchers compared two regions with different soil selenium levels. They found that the area with adequate selenium had a significantly lower prevalence of thyroid disorders (18% compared to 30.5% in the selenium-deficient region).

VitaRx Tip

Did you know that just one Brazil nut may supply up to 91 μg of selenium? That's more than the daily recommended amount for adults! So, enjoy Brazil nuts in moderation to avoid exceeding your selenium needs.

Symptoms of selenium deficiency

Not getting enough selenium has been linked to symptoms like hair loss, fatigue, brain fog, muscle weakness, and a weakened immune system. These symptoms often overlap with those of an underactive thyroid, making it tricky to pinpoint the exact cause.

Who's at risk?

While anyone may develop selenium deficiency, certain groups are more susceptible:

People living in selenium-deficient regions: If the soil in your area is low in selenium, the local produce and livestock may also lack this essential mineral.
People undergoing kidney dialysis: The dialysis process may deplete selenium levels in the blood.
Those with HIV/AIDS: This condition may impair nutrient absorption, including selenium.
People with gastrointestinal disorders: Conditions like Crohn's disease or celiac disease may reduce nutrient absorption.
People following restrictive diets: Vegans or vegetarians not consuming selenium-rich plant foods may be at risk.

If you suspect you have a selenium deficiency, it's important to consult a healthcare professional. They may perform tests to measure selenium levels in your blood or hair. Proper diagnosis is crucial before starting any supplementation.

Get your personalized vitamin recommendations in less than 3 minutes.

Take the Health Quiz

Get your personalized vitamin recommendations in less than 3 minutes.

Take the Health Quiz

Boosting your selenium intake

So, how can you ensure you're getting enough selenium?

Selenium-rich foods

Adding selenium-rich foods to your diet is a great start:

Brazil nuts: Just one or two may meet your daily requirement!
Seafood: Tuna and shellfish are excellent sources.
Organ meats: Foods like liver and kidneys are rich in selenium.
Eggs and chicken: More common foods that still pack a selenium punch.
Whole grains: Barley, brown rice, and oats provide selenium.
Sunflower seeds: A convenient snack that's also a good source.
Mushrooms: Certain varieties, like shiitake and button mushrooms, contain selenium.

Dos and don'ts of getting enough selenium

Do’s

Do eat a balanced diet including selenium-rich foods.
Do consult your healthcare provider before starting supplements.
Do be mindful of selenium intake if living in low-selenium areas.

Don’ts

Don't overconsume high-selenium foods like Brazil nuts.
Don't self-diagnose a selenium deficiency without professional advice.
Don't ignore symptoms that may indicate thyroid issues.

Recommended intake

According to health guidelines, the recommended daily intake of selenium is approximately 55 mcg for men and women. If a deficiency is identified, your healthcare provider may recommend a higher dosage to restore optimal levels.

Important note: While selenium is essential, it's crucial not to exceed the tolerable upper intake level, which is 400 μg per day for adults.

Always use supplements safely

Excessive intake may lead to selenium toxicity, so supplementation should be monitored by a professional.

Frequently asked questions (FAQ)

Here are some of the most frequently asked questions about selenium.

Final thoughts

Selenium deficiency may be the hidden culprit behind your thyroid issues. This vital mineral plays an indispensable role in thyroid hormone production and overall gland function. Ensuring you receive the right amount—neither too little nor too much—is essential.

By including selenium-rich foods in your diet and considering supplementation under professional guidance, you may support better thyroid health.

Dr. Dimitar Marinov, MD, MBA, PhD, says, "Ensuring adequate selenium intake is vital for optimal thyroid function, particularly for individuals at risk of deficiency, and consulting with a healthcare professional is essential before considering supplementation to support overall thyroid health."

Sources and references

Author

Stephanie Wright

Stephanie brings over 13 years of diverse nursing experience to the table, having honed her expertise in critical care, mental health, and utilization management. Her journey as a registered nurse across these various healthcare sectors underscores her adaptability and deep commitment to patient care.

Fact checker

Dr. Dimitar Marinov

Dr. Marinov has years of experience in scientific research and preventive and clinical medicine. His publications in peer-reviewed journals are on nutritional status, physical activity, and musculoskeletal disorders among adolescents.

At VitaRx, we're not just passionate about our work — we take immense pride in it. Our dedicated team of writers diligently follows strict editorial standards, ensuring that every piece of content we publish is accurate, current, and highly valuable. We don't just strive for quality; we aim for excellence.

While you're at it, here are some other relevant articles you might be interested in.

6 minutes read

Get your personalized vitamin recommendations in less than
5 minutes.

Take the Health Quiz

Get your personalized vitamin recommendations in less than
5 minutes.

Take the Health Quiz