Signs and Symptoms of Selenium Toxicity

Signs and Symptoms of Selenium Toxicity – Are you Taking Too Much?

Serious Selenium Toxicity is Rare but Minor Excess Is More Common Than you Think

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Selenium is one of the most important micronutrients in your body when it comes to your thyroid. 

Selenium also plays an important role in regulating enzymes that help protect your cells from free radicals. 

These enzymes are known as selenium-dependent enzymes (1) and they are important for many cellular pathways in your body. 

To take matters a step further, it’s not uncommon for many people to suffer from low-grade selenium deficiency

Minor deficiency is common due to rampant due to modern intensive agricultural farming methods (2) which have stripped the soil of its nutrients. 

Today this soil only contains a fraction of what it used to. 

And this soil depletion has real consequences for people like you and me when we consume fruits and vegetables. 

For these important reasons, selenium is often included in many over-the-counter supplements. 

And it is the minor toxicity that can occur from these supplements that I want to focus on today. 

You see, it’s actually quite rare that humans suffer from overt selenium toxicity. 

But it’s not uncommon for people to accidentally take too much in supplement form as they attempt to replace low levels caused by issues like soil depletion. 

And the side effects of low-grade selenium toxicity, or selenium overdose, can be difficult to identify and may actually mimic some of the same side effects as selenium deficiency. 

Another group of patients at risk for selenium toxicity is thyroid patients. 

These patients tend to take higher doses than selenium in an attempt to bring down thyroid antibodies in diseases such as Hashimoto’s thyroiditis

And while there is evidence that this can be effective, it’s also potentially harmful if the wrong dose is used. 

Let’s break it down. Today you will learn:

  • The early warning signs of selenium toxicity
  • Warning signs that you are taking too much selenium in supplement form
  • More serious side effects of selenium toxicity (these are rare)
  • How to know if you are taking the right amount of selenium and what dose you should be taking
  • And more

Let’s jump in…

Minor Problems & Symptoms (Usually from taking too much in supplement form)

While serious selenium toxicity is incredibly rare, minor selenium toxicity is not all that common. 

Selenium is found in MANY over-the-counter supplements including multivitamins, thyroid support supplements, adrenal support supplements, women’s daily vitamins, and specific selenium only supplements. 

If you aren’t paying attention, or if you are someone who is simply sensitive to selenium, it’s possible that you may be taking too much. 

It’s not too much in the sense that it will cause you serious problems but it could definitely be enough to prevent you from feeling at 100%. 

The following signs may indicate that you need to back off on your selenium dose: 

#1. Hair Loss – Selenium deficiency can also cause hair loss which means many people with hair loss use selenium. Just be sure that your dose isn’t too high or you may cause the same problem. 

#2. Brittle Nails – Selenium toxicity can cause changes to your nail beds including discoloration in your nails. 

#3. Fatigue – Fatigue and low energy may stem from thyroid problems that excess selenium may exacerbate. 

#4. Gastrointestinal (stomach) problems – This may include having an upset stomach, feeling minor stomach pains, changes in bowel movements, and so on. 

#5. Joint Pain

#6. Nausea – Nausea that sticks with you throughout the day may be an indication your selenium level is too high. 

These minor symptoms should completely fade within 2-3 months once you stop taking selenium. 

Serious problems that indicate you have Selenium Poisoning

Serious and life-threatening selenium toxicity can and does occur but is incredibly rare among humans. 

It’s much more common in livestock because the primary source of selenium depends on soil concentrations. 

If animals are consuming soil that is heavily concentrated in selenium then they may start to experience signs of excess. 

And these symptoms can also occur in adults, though it’s incredibly rare that they occur. 

Most of the time, selenium excess is typically only minor and comes from excessive use of over-the-counter supplements. 

And most people stop using the offending agent when they start to feel the minor issues listed above. 

Having said that, let’s at least mention some of the more serious side effects: 

#7. Neurological problems

#8. Paralysis

#9. Selenosis

What to do If you Experience These Signs?

The good news is that there isn’t much you need to do to “treat” the problem as it will take care of itself. 

Any extra selenium is typically eliminated from the body within 1-2 days after being consumed, provided your organs are functioning at 100%. 

But, if you do experience the warning signs of excess selenium then you should take steps to try and find the source of selenium exposure. 

This is most likely in whatever supplements you are taking but it could also be from the food you are eating or another environmental source.  

How Much Selenium Should you Take Each Day?

Well, it depends on who you ask…

The RDA for selenium is somewhere around the 40-55mcg range depending on your age (3). 

But the problem with the RDA is that it’s set for 97% of the population (which leaves out a small percentage of people), the RDA is set for only the minimum amount necessary to avoid deficiency, and it doesn’t take into account conditions where taking more may actually be beneficial. 

There’s real evidence to suggest that using the RDA is not sufficient for most people, and while it may stave off overt deficiency it’s not enough for people to thrive. 

Because of these known issues, other organizations and physicians have recommended higher doses than the 40-55mcg range. 

And while these doses are better at helping people feel better and improving symptoms, they also run a slight risk that you may take too much. 

Daily selenium intake in the 400mcg to 600mcg range has been recommended in many circles and many patients have had great success using these doses. 

In fact, studies have shown that humans can tolerate 600mcg per day for long periods of time without any issue. 

Even though the studies have shown this, I have personally seen people experience issues when consuming 600mcg per day. 

My recommendation is to stick to the 100mcg to 200mcg per day range. 

This ensures that you are supplementing with a sufficient amount to meet your body’s requirements but also not too much so that you won’t tip yourself over the edge with selenium found in your diet. 

I should point out, though, that some people see improvements in conditions like Hashimoto’s thyroiditis at higher doses. 

How to Avoid Selenium Toxicity

The best way to avoid selenium toxicity is to be vigilant about the over-the-counter supplements that you are taking day to day. 

If you are otherwise healthy, then you should always try to get as much selenium as you can from your diet. 

Selenium-rich sources of food include:

  • Brazil nuts
  • Fish
  • Ham
  • Pork
  • Beef
  • Chicken
  • Eggs
  • Brown rice
  • Oatmeal
  • Spinach
  • Bananas

If you are healthy then you may be able to get all of the selenium that you need from these sources. 

When possible, remember to try and consume organic versions of these foods as the nutrient contents are likely to be much higher (4). 

If you have a medical condition in which taking excess selenium may be beneficial, then pay close attention to how much you are taking in your supplement form and how much you may be getting from your foods. 

As long as you supplement in a low dose, in the range of 100mcg to 200mcg per day, you should not run into any issues of selenium toxicity even if you are also eating organic healthy foods high in selenium. 

People typically don’t run into issues until they hit that 600mcg per day or higher dose. 

Now I want to hear from you:

Do you think that you are taking too much selenium?

Do you have any of the signs or symptoms listed above?

How much selenium are you taking each day?

Which symptoms or side effects are you experiencing?

Leave your questions or comments below! 





warnings signs you are taking too much selenium

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About Dr. Westin Childs

Hey! I'm Westin Childs D.O. (former Osteopathic Physician). I don't practice medicine anymore and instead specialize in helping people like YOU who have thyroid problems, hormone imbalances, and weight loss resistance. I love to write and share what I've learned over the years. I also happen to formulate the best supplements on the market (well, at least in my opinion!) and I'm proud to say that over 80,000+ people have used them over the last 7 years. You can read more about my own personal health journey and why I am so passionate about what I do.

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