Author – Phoebe Chan – BSc (Hons) Nutrition and Human Health
Selenium is a trace mineral, meaning it is only needed in small quantities. It is an essential component of various enzymes and proteins, called selenoproteins, that help to make DNA and protect against cell damage and infections (1). It is also particularly important in the role of women’s health, specifically to do with hormonal health, thyroid health and immunity. This tiny mineral can play a huge role in keeping these systems in check.
What Is Selenium?
Selenium is known as an essential mineral and is a powerful antioxidant. It is only needed in small amounts and is naturally found in foods such as nuts, seafood, meat and grains and can also be taken as a supplement.
Most selenium in the body is stored in muscle tissue, although the thyroid gland holds the highest concentration of selenium due to various selenoproteins that assist with thyroid function (1). Selenium is a key component for approximately 25 selenoproteins, including the glutathione peroxidases, which are crucial enzymes for detoxification and protecting cells from oxidant damage (2).
The Recommended Daily Allowance (RDA) for adult women over the age of 19 is 55 micrograms daily, increasing to about 60-70 micrograms during pregnancy and lactation (1).
Selenium and Hormonal Health
Oestrogen Metabolism and Reproductive Hormone Balance
All cells in the body are susceptible to free radical damage; however reproductive tissues are especially sensitive. This makes selenium especially important for fertility and pregnancy , as its antioxidant properties help protect these tissues from oxidative stress. Low selenium levels have been linked to miscarriage and pregnancy complications (3).
One of selenium’s most important roles is supporting glutathione peroxidase, an antioxidant enzyme. This is especially important in reproductive tissues, where oxidative stress can interfere with ovulation, sperm development or embryo implantation.
When the body has optimal selenium levels, glutathione peroxidase can work more effectively. This leads to healthier cells, more stable hormone activity and stronger defence against inflammation that can disrupt reproductive processes over time (4).
Menopause and PMS
Selenium can be really useful during the time of menopause. It has been particularly good for someone who suffers from hot flushes as it is said to help alleviate such symptoms (5). It is able to do this through contributing to the normal function of the thyroid gland. In addition, selenium contributes to the normal functioning of the immune system such as the maintenance of nails and hair (6).
Selenium and Thyroid Health
Low levels of selenium can cause problems as it is harder for the thyroid to make hormones. It also makes it harder for the body to convert thyroid hormones into the correct form. This is because selenium is a fundamental component of various seleno-proteins, their role includes:
- Regulating thyroid hormone synthesis
- Supporting the conversion of thyroxine (T4), to triiodothyronine (T3)
- Protecting the thyroid’s tissues whenever the thyroid is affected by oxidative stress
Selenium is also a key regulator of thyroid hormone levels. A number of enzymes composed around selenium are responsible for making sure thyroid hormone levels are neither too low or too high. When there is too little selenium available for the body to make these enzymes, appropriate levels can’t be maintained which can cause troubling symptoms (7).
Selenium and Immunity
The immune system is our body’s defence network against infections, diseases, bacteria and pathogens. One nutrient that plays an important role in this system is selenium, which is known for its antioxidant properties, therefore reducing oxidative stress in the body.
Selenium supports both branches of the immune system. It helps maintain proper function of T-lymphocytes, which are important for co-ordinating immune responses, and supports natural killer (NK) cells, which help the body to detect and destroy virus-infected cells. Adequate selenium levels are associated with healthy antibody production, which is essential for long-term immune defence.
There is also research suggesting selenium status may influence how certain viruses behave. In laboratory and animal studies, low selenium levels have been linked to weaker immune responses and, in some cases, changes in viral mutation patterns.
Overall, selenium helps to ensure that immune function works properly by supporting antioxidant defences and the normal activity of immune cells (8).
How to Get Selenium
Dietary selenium occurs as selenocysteine (SeCys) and selenomethionine (SeMet), with content varying widely across foods and regions. Brazil nuts are the richest natural dietary source of selenium, primarily in the form of SeMet. Even a single nut can exceed daily requirements, therefore making them a potent but potentially excessive source if consumed regularly.
Seafood, including tuna, sardines, salmon, oysters and shrimp provide up to 5 ug/g. Offal including beef kidney, liver and heart is also abundant in selenium, whereas poultry, pork, eggs and dairy products provide moderate amounts.
The selenium content of whole grains, legumes, and mushrooms is primarily dependent upon soil consumption. Garlic, onion, broccoli and cabbage accumulate selenium in detoxifying forms such as Se-methyl-selenocysteine.
Conclusion
Selenium is an essential mineral with powerful antioxidant properties, playing a key role in women’s hormone balance, thyroid function and immune health. Maintaining a balanced diet rich in selenium support energy levels, mood and overall wellbeing. However, it is always important to consult a healthcare practitioner before any supplementation.
FAQ’s (Frequently Asked Questions)
What is selenium and why is it important for women?
Selenium is an essential trace mineral that acts as a powerful antioxidant. It helps protect cells from oxidative stress and supports key functions such as hormone regulation, thyroid activity, and immune defence—areas that are especially important for women’s overall health.
How does selenium support hormone balance in women?
Selenium plays a role in regulating hormones by supporting antioxidant activity and reducing inflammation, which can impact hormonal signalling. It may also help maintain balance during periods of hormonal fluctuation, such as menstruation, pregnancy, and menopause.
Why is selenium important for thyroid health?
The thyroid contains high concentrations of selenium. It is needed to convert thyroid hormones into their active form and helps protect the thyroid gland from oxidative damage, supporting healthy metabolism and energy levels.
References
- https://nutritionsource.hsph.harvard.edu/selenium/
- https://pmc.ncbi.nlm.nih.gov/articles/PMC4210904/
- https://drbrighten.com/selenium-benefits-for-hormones-and-thyroid/
- https://holplus.co/benefits-of-selenium-sexually/
- https://www.birchandwilde.co.uk/blogs/news/super-selenium-do-you-know-the-top-5-benefits-for-you?srsltid=AfmBOopQX8A9rfJqpS8uM7IiJHmFfdAQ0KOS_o_VH4kBNr0xFlaibaiz
- https://www.bears-with-benefits.co.uk/pages/selenium-what-it-is-effects-and-intake
- https://www.womenshealthnetwork.com/thyroid-health/selenium-benefits-for-your-thyroid/
- https://www.healthspan.co.uk/guides/selenium-benefits-uses/?srsltid=AfmBOopilKLlMRmIUSAMT23ri8sdHyGgcyT-hli1XA9otD0EHQ1NMjf3
