
Introduction
Selenium is an important trace mineral which means the human body needs it in small quantities. [1]
This nutrient has antioxidant properties and is involved in defence against oxidative stress. [2]
It exists in 2 forms, inorganic and organic and both can be good dietary sources. [1]
However, the amount of selenium in plant based-foods can vary widely depending on the selenium content of the soil in which it is grown.
Also, men usually tend to have higher selenium levels usually than women. [1]

- Selenium components are quite efficiently absorbed by humans and the absorption rate is higher than 80%. [3]
- The bioavailability of selenium might vary significantly for different food groups though and bioavailability from fortified foods and supplements is lower than naturally occurring dietary forms of selenium. [2,3]

- Most of the selenium is stored in skeletal muscles, approximately 28% to 46%, followed by the muscles (30%), liver (30%), blood plasma (10%), and kidneys (15%). [1,3]
- Blood and urine concentrations reflect selenium intake, however, longer-term intakes can be monitored by the hair and nail selenium content. [1]

- Selenium is mainly excreted through urine. [2]
- Breath can contain volatile metabolites when a large amount of selenium is being excreted. [2]
Body Functions

Recommended Daily Intake

Deficiency Symptoms

Selenium Food Sources

Excessive Intake/ Toxicity Side Effects

Groups At Risk of Selenium Deficiency
Selenium Interaction With Other Nutrients
- Iodine – Selenium deficiency could exacerbate iodine deficiency, potentially increasing the risk of cretinism in infants. [1]
- Vitamin C & Vitamin E – Selenium acts in synergy with the antioxidant vitamins, vitamin C and vitamin E, by regenerating them from their oxidised forms and promoting maximal antioxidant protection. [6]