Selenium is an essential trace mineral that's found in soil, water and plants and it's well known for its antioxidant ability.
It's involved in many important functions in your body including hair, skin and nail health, thyroid function, DNA synthesis and fertility.
Selenium benefits
How does Selenium help your skin, hair and nails?
Selenium is essential for the production of the thyroid hormones that help regulate hair growth. As Selenium is more concentrated in the thyroid than in any other organ, it's important for the proper functioning of thyroid hormone.
Free radicals can contribute to damage that weakens hair follicles. As a key component of the enzyme glutathione peroxidase, Selenium can neutralise those free radicals and prevent damage.
Additionally, Selenium supports various proteins, like keratin, that have a known role in maintaining healthy hair and nails.
It could also have potential in reducing hair loss. One study investigated how Selenium could help with hair loss due to its involvement in hair production. Newly forming hair was shown to take up Selenium after receiving trace elements from the blood.
Selenium and the thyroid
Since Selenium is highly concentrated in the thyroid and acts as a catalyst for the production and metabolism of thyroid hormones, research now suggests there is a link between Selenium deficiency and impaired thyroid function. It also helps protect the thyroid gland against oxidative damage and from antibodies that can create thyroid disease.
Low Selenium levels have also been connected with an increased risk of thyroid disease.
Selenium as an antioxidant
Selenium helps reduce free radicals in your body and prevents them from damaging cells, slowing down premature ageing and supporting the immune system.
Selenium is used to produce enzymes called selenoproteins and it's an essential component of the enzyme glutathione peroxidase.
How selenium supports the immune system
Selenium is needed for your immune system to function properly. It helps stimulate the production and activities of white blood cells and defend against infections and viruses. Its antioxidant properties also help lower oxidative stress.
Selenium deficiency has been shown to affect immune cell function and may lead to a slower immune response.
Selenium supports the heart
Selenium may benefit heart health in a number of ways, including helping reduce inflammation and oxidative stress, increasing blood flow and preventing the oxidative modification of fats.
Clinical trials have found that Selenium supplementation decreased inflammatory markers in the body. The same review found that Selenium also helped raise levels of Glutathione.
Selenium deficiency & depletion
While low levels of Selenium are fairly common, a Selenium deficiency is rare. There are several reasons why someone might have low Selenium levels:
-
Poor diet: Selenium is removed from a lot of processed and refined foods
-
Where you live: The content of Selenium in soil differs a lot depending on the location
-
Smoking: Smokers have been shown to have lower levels of Selenium compared to non-smokers
-
Age and mobility: The risk of Selenium deficiency increases in the elderly living in residential or nursing homes
-
Digestive disorders: such as Crohn’s disease, which impairs your ability to absorb nutrients from food efficiently
-
Other health conditions: Undergoing kidney dialysis or living with HIV
Sources of Selenium
Your body can't make Selenium so you need to get it from your diet!
Selenium-rich foods
Foods rich in Selenium include:
-
Nuts, particularly Brazil nuts
-
Seafood, particularly tuna, halibut, prawns and sardines
-
Meats, including chicken and beef
-
Eggs
-
Cooked brown rice
-
Mushrooms, particularly shiitake or white button varieties
-
Fresh broccoli, cabbage and spinach
-
Brewer’s yeast and wheat germ
The amount of Selenium found in food is dependent on its concentration in the soil and water the food is grown in. Soil quality can vary widely around the world, and as a result, people’s selenium levels also vary geographically. It's generally considered to be low quality in the UK and Europe.
Selenium supplements
Taking Selenium supplements is a convenient way to help increase your selenium intake, especially since the quantity of Selenium in food is hard to determine.
Selenium is usually found as part of a skin, hair and nails complex combined with other nutrients like Biotin and Zinc.
Selenium RDA
The amount of Selenium you need per day is:
-
75μg a day for men (19 to 64 years)
-
60μg a day for women (19 to 64 years)
If you take Selenium supplements, it's important not to take too much as this could be harmful. Taking 350μg or less a day of Selenium supplements is unlikely to cause any harm.
Summary
Selenium is an important mineral that's essential for the proper functioning of your body, especially skin, hair and nail health, thyroid function and fighting against free radicals.
While we don't need a lot of it per day, the low quality of soil food is grown in means the selenium content could also be low.
