Selenomethionine is one of the main natural forms of selenium.
It combines with proteins in the body to form antioxidants called selenoproteins.
These compounds help protect againstfree radicals, the unstable molecules that can cause damage to cells in your body.
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That means some supplement products may not contain what the label says.
No supplement is intended to treat, cure, or prevent disease.
Much of the research on SeMet has centered around thyroid disease, cancer, and heart disease prevention.
It also has been studied for its role in mental health and how it may prevent cognitive decline.
Thyroid Disease
Selenium levels in the human body are highest in the thyroid gland.
The mineral plays a key role in thyroid metabolism and making thyroid hormone.
Because of this, selenomethionine has been studied for its effects on thyroid diseases.
For the study, participants were given either 83 mcg of oral SeMet or aplaceboevery day for four months.
They were evaluated at around 10 weeks gestation, 36 weeks gestation, and about six months after delivery.
What Is Keshan Disease?
Keshan disease is the only known disorder linked directly to low levels of selenium.
It damages the heart muscle, leading to heart failure and other heart problems.
Cancer
Selenomethionine does not seem to help with cancer prevention.
They also reported that SeMet is one of the best organic ways to boost selenium levels in the body.
More clinical trials are needed to better understand the SeMet-heart risk connection.
However, study results are mixed.
Alzheimer’s diseaseis often diagnosed in older people and leads to progressive cognitive decline.
Yet there is no clear evidence to support a role for seleniumin SeMet form or otherwisefor treating it.
Selenium may one day be shown to prevent cognitive decline, but currently more studies are needed.
What Are the Side Effects of Selenomethionine?
Generally, side effects will only occur when there is too much selenium in the body.
Be sure to follow the directions on the product label.
What Is the Difference Between Selenomethionine and Selenium?
Selenomethionine is a natural form of selenium.
It is the same form of selenium found naturally in the foods you eat.
Seafood, nuts, and meat are all good dietary sources of selenomethionine.
Precautions
Selenomethionine can be toxic at high doses, especially when taken long-term.
Taking lower doses for long periods of time may increase your risk of developing diabetes.
Dosage: How Much Selenomethionine Should I Take?
The National Academies of Sciences sets the suggested daily amount needed for vitamins and minerals, including selenium.
The RDA includes your intake from all sources, such as food, drinks, and supplements.
What Happens if I Take Too Much Selenomethionine?
Taking too much selenium for long periods can cause selenosis.
This is the medical term for selenium poisoning.
People with selenosis may experience symptoms such as:
Selenosis can also cause nerve damage.
It may have a similar effect if you take it with aspirin.
In a rat study, selenium increased or extended the time barbiturates lasted.
These findings may not apply to humans.
In these cases, a selenium supplement may be helpful.
SeMet supplements are most often available in the form of tablets or capsules.
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