Selenium Benefits Backed by Science: Slower mental decline, Lower Cancer Risk and More

Selenium was first thought to be potentially dangerous and toxic even for our health; It is now one of the most commonly used supplements worldwide.

We are talking about selenium and its popularity among those who are looking to enhance their health.

If you are interested in learning how selenium can help enhance the quality of your health, then we highly recommend dedicating your time to the article that follows.

Today, we are here to talk to you about 7 of the biggest health benefits that selenium offers.

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7 Health benefits of selenium that are supported by science

Selenium is a well-known trace mineral. Selenium is of essential importance for our health – and has benefits for both physical and mental health.

It took a long time for this mineral to be finally recognized as beneficial for our health and used as such. Before 1957, selenium considered to be toxic. There is still a lot of controversy revolving around selenium.

In fact, scientists are looking into the idea of selenium contributing to diabetes type 2. We don’t know yet if it caused diabetes or not. Now let’s take a look at the seven biggest health benefits of selenium.

1) Represents a powerful antioxidant

Selenium is one of the great antioxidants that help shield our body against oxidative stress and free radicals. You see, the free radicals in the body cause cell damage. Such free radicals are produced daily as a part of the normal processes in the body.

Although having some free radicals is considered to be essential for health, having too much of them can lead to oxidative stress.

Oxidative damage, on the other hand, is linked to a number of serious health issues. The list includes:

So, what selenium does, is neutralizing the excess free radicals in the body, thus protecting us from the oxidative damage and the health issues that are to come because of it.

But that is not all. Selenium is also working closely with what is known to be the “master antioxidant” in the body or otherwise called glutathione.

Glutathione peroxidase acts similarly to some of the other great antioxidants in the body, such as Vitamin C and Vitamin E. It has been scientifically proven to be able to protect against chronic disease and other health issues. Luckily, selenium is working towards maximizing its activity.

2) May lower the risk of cancer

As we mentioned before, oxidative stress increases the risk of cancer. The good news is that by having a strong antioxidant as selenium, you can act to lower your risk of certain cancers, especially prostate cancer.

Did you know that as much as 1 in 9 men will likely develop prostate cancer during their life? Knowing that it is good to have something that will increase your fighting chance.

This is all explained by selenium’s ability to destroy cancer cells, but also to reduce the oxidative stress and boost your immune system, which we will talk about in a moment. A review published in the Scientific Reports looked at a total of 69 studies, investigating the potential abilities of selenium to lower the risk of cancer.

The results showed that the participants who had high serum selenium levels were less likely to develop cancer. Selenium has been proven especially beneficial when it comes to preventing certain types of cancer, such as lung, prostate, breast, and colon cancer.

Women with cervical and uterine cancer have also managed to improve their quality of life thanks to selenium supplementation that helped relieve some of the chemotherapy side effects. If you are someone who has a family and/or medical history of cancer, it is recommended that you increase your daily selenium intake.

3) Protects against heart disease

Cancer is not the only chronic disease that selenium offers to keep away from you. The selenoprotein is also said to help against heart disease, mainly by acting as an antioxidant. Selenium reduces the oxidative damage in the body, which is known to cause inflammation.

Inflammation contributes to the development of heart disease, among other health issues, and as such, is marked as one of the biggest risk factors for heart disease. 

A review published in The American Journal of Clinical Nutrition investigated the use of selenium in patients with coronary heart disease. Researchers were analyzing the results of 25 clinical studies.

They concluded that a 50% increase in selenium blood levels resulted in a 24% decrease in the risk of heart disease. That being said, selenium is a great addition to the diet of anyone struggling with heart disease or the high risk of developing such serious health issues.

4) Slows down the mental decline

Most of the time, when talking about enhancing human cognition and preventing mental decline, we only focus on Omega-3 fatty acids alone. And while there is no denying of their cognition-enhancing abilities, Omega-3 fatty acids are not the only ones able to slow down the natural mental decline.

Scientists have discovered that selenium is just as important as Omega-3 fatty acids in the preservation of our good mental health and cognition.

They discovered that selenium works together with Omega-3 fatty acids, helping to prevent their breakdown and enhance their benefits. The authors of a 2009 study argued that the increased selenium levels, rather than the increased Omega-3 fatty acids levels, were the reason for the better cognition in high fish consumers.

Some researchers have even discovered that Alzheimer’s disease patients have lower selenium levels, which may be the cause of their cognitive decline. In addition, food rich in antioxidants, such as selenium, was found helpful to improve the symptoms and cognition of those with Alzheimer’s disease.

As little as one Brazil nut a day has been found beneficial in improving mental cognition in those with mild cognitive impairments.

5) Boosts the immune system

We cannot talk about selenium without mentioning its ability to boost the immune system. By reducing the oxidative stress levels in the body, selenium can reduce the present inflammation, thus enhancing our immunity. Studies have found that a selenium deficiency is linked to a slower immune response, hence a weaker immune system.

In addition, oral supplementation with selenium has improved the symptoms in patients diagnosed with HIV. Such supplementation has also strengthened the immune system of those struggling with severe infections such as tuberculosis and hepatitis C, among others.

6) Supports the thyroid health

Doctors believe that having a healthy thyroid gland is the answer to having good physical and mental health. You see, it is through the production of thyroid hormones, especially one thyroid hormone known as thyroxine (T4), that the thyroid gland is able to control just about everything that is happening in the body.

From our metabolism, heart function, brain development, and even bone development, our thyroid gland maintains bodily functions.
Low selenium levels have been linked to an increased risk of Hashimoto’s thyroiditis, which is the most common type of hypothyroidism in men

A study that included 6,000 participants found that those with selenium deficiency have a higher risk of hypothyroidism and autoimmune thyroiditis.

Oral selenium supplementation has also resulted in an improvement of symptoms and overall well-being in those with Hashimoto’s thyroiditis.

7) Helps with asthma

And last but not least important is the ability of selenium to help soothe your asthma symptoms. For those of you who did not know, asthma is a chronic disease that causes the airways to become inflamed.

Common symptoms include wheezing, coughing, and shortness of breath. Where is inflammation present, selenium can help.

Having a better selenium status has been linked to a better lung function in patients with asthma, according to research published back in 2011.

The same research also suggests that asthmatic patients have lower selenium levels, which may contribute to the severity of their symptoms. Some researchers also suggest that introducing enough selenium during pregnancy can help reduce the child’s risk of asthma, although more investigation is required.

What is the recommended daily intake of selenium?

To gain all of the previously discussed selenium benefits, one should use this trace mineral daily. The recommended daily allowance for selenium is 55 mcg for adults.

We see a variation in the numbers while talking about pregnant and breastfeeding women. And so, pregnant women are instructed to introduce up to 60 mcg selenium per day, while breastfeeding women need to intake up to 70 mcg selenium daily.

Food sources of selenium that you need to know about

Getting enough selenium in your body will not be a problem since selenium is found in so many delicious food sources.

Whole grains and animal products are the biggest food sources of dietary selenium, but there is also some selenium in fresh fruits and veggies too.

To add more of this powerful antioxidant to your diet, we recommend introducing more of the following foods:

  • Brazil nuts

  • Tuna

  • White bread

  • Eggs

  • Cooked brown rice

  • Sardines

  • Sunflower seeds

  • Chicken breast

  • Halibut

  • Shiitake mushrooms, etc

But the selenium concentration depends, not only on the food source but more on the soil in which the crop has been grown. And so, a 2017 study compared the selenium concentration in Brazil nuts grown in different regions.

Of all Brazil nuts that were analyzed, the results showed that only one region produced the Brazil nuts that provided up to 288% of the recommended daily requirements.

If you are worried that you do not introduce adequate selenium to your body, we advise investing in a quality selenium supplement. Selenium supplementation is also highly recommended to anyone who struggles with low selenium levels. Do consult a doctor whenever you decide on purchasing selenium supplementation or any other supplementation in general.

Selenium deficiency is not considered to be a common occurrence. The reason for the low prevalence of selenium deficiency lies in the quality soil content on a global level.

In most parts of the world, the soil has high selenium levels, so much so that it is enough to satisfy the daily need for selenium. So far, selenium deficiency has been registered in some Chinese regions, but the low selenium levels have been quickly improved with the use of proper selenium supplementation.

Warnings and risks that should not be ignored

We mentioned 400 mcg selenium to be the upper daily limit for adults. While the selenium intake from natural, dietary sources is rarely the reason for selenium toxicity, this is still a possibility.

The risk of selenium toxicity is increased when this powerful antioxidant is introduced in the form of supplementation.

Those with low selenium levels who rely on selenium supplementation need to keep an eye on their dietary selenium intake. Do respect and follow the provided instructions in order to avoid selenium poisoning. High doses of selenium have been reported to cause the following health issues:

  • Fatigue

  • Irritability

  • Nausea

  • Vomiting

  • Brittle nails

  • Hair loss

  • Tremors

  • Skin rash

  • Muscle soreness

  • Kidney failure

  • Heart failure

  • Death

In case you are using any prescription and/or non-prescription medications and/or dietary supplements, do consult a doctor. Selenium supplements can interact with some medications, such as the well-known chemotherapy drug called cisplatin.

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Selenium is a popular trace mineral found in many delicious foods such as Brazil nuts, tuna, sardines, bread, and eggs. Like any other mineral, selenium, too, Selenium has many benefits and takes part in a number of important bodily functions.

As we discussed before, selenium can have a lot of benefits. But we want to remind you about the increased risk of selenium overdose that comes with this mineral introduced in high doses.

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