Selenium. How it works and Why you need it

Selenium. How it works and Why you need it

8 Science-Backed Health Benefits of the essential mineral Selenium. Did you know for example that it enhances fertility and protects against cancer? Read more here.


Though you may have never heard of the micronutrient selenium, it is vital to your health.

Selenium is an essential trace mineral that our bodies need to function. It contributes to:

+ normal spermatogenesis (the production of sperm)
+ the maintenance of normal hair and nails
+ normal thyroid function
+ the normal function of the immune system
+ the protection of cells from oxidative stress

Good sources of selenium include brazil nuts, fish, meat and eggs.

Selenium plays a critical role in fertility and important processes in our body, including our thyroid function. It also helps protect our body from damage caused by oxidative stress and helps the immune system work properly.



Selenium plays a critical role in fertility and important processes in our body, including our thyroid function. It also helps protect our body from damage caused by oxidative stress and helps the immune system work properly. Scientific studies show that selenium deficiency may contribute to hair loss, a weakened immune system, male infertility, age-related mental decline, increased cancer risk, and heart disease.

Let’s delve into some of the science below:


Selenium is critical for human health and reproductive functions. Studies have indicated that selenium levels outside the recommended range could be a factor in both male and female fertility, and that selenium supplements can help to improve semen quality at the same time as lowering the risk of miscarriage. For example:

+ A scientific review published in 2021 found selenium supplementation can significantly improve sperm fertility parameters.


The fact that there’s more selenium in thyroid tissue than in any other organ in the human body, tells us something about the influential role this mineral plays in the proper functioning of our thyroid gland. And a healthy thyroid gland is important, as it regulates our metabolism and controls growth and development. For example, selenium is essential for the production of the thyroid hormones that help to regulate hair growth and strong evidence links thyroid dysfunction to hair loss. Furthermore, some clinical studies have shown that lack of selenium will increase the prevalence thyroid dysfunction and several kinds of thyroid diseases. For example:

+ A study including over 6,000 people found that low levels of selenium were associated with abnormal thyroid function.
+ A 2021 review of autoimmune thyroiditis (AITD) and Hypothyroidism clearly identified selenium deficiency as an important risk factor for Autoimmune thyroid diseases (AITD).


Selenium is crucial for the health and proper functioning of our immune system which keeps our body healthy by identifying and fighting off potential threats including bacteria, viruses, and parasites. Selenium deficiency has long been recognized to negatively impact immune cells, thereby increasing the risk of bacterial and viral infections. For example:

+ A review comparing results from a wide variety of studies showed that selenium deficiency harms immune cell function and may lead to a slower immune response.
+ A review analysing data from epidemiologic studies and intervention trials showed that selenium supplements help boost the immune systems of people with influenza, tuberculosis, HIV and hepatitis C.
+ A review of studies found an association with selenium deficiency and an increased risk of death and disease progression in people with HIV, while selenium supplements were shown to lead to fewer hospitalizations and an improvement in symptoms for HIV patients.


Selenium is a powerful antioxidant that protects our cells against oxidative stress and helps defend our body from chronic conditions. Oxidative stress is caused by an excess of free radicals in the body. Smoking, alcohol use, and stress can cause an excess of free radicals. This leads to oxidative stress, which damages healthy cells. Antioxidants like selenium help reduce oxidative stress by keeping free radical numbers in check to lessen our risk of diseases, including cancer, diabetes, Alzheimer’s disease, mental disorders, cardiovascular disorders, fertility impairments, inflammation, and infections. They work by neutralizing excess free radicals and protecting cells from damage caused by oxidative stress. For example:

+ A controlled study including 465 coronary artery disease patients found selenium supplementation leads to an increase in antioxidative glutathione peroxidase 1 (GPx1) activity.


Research suggests that higher blood levels of selenium may protect against certain cancers, while supplementing with selenium may help improve quality of life in people undergoing radiation therapy. For example:

+ A review of 69 studies that included over 350,000 people, found that having a high blood level of selenium was associated with a lower risk of certain types of cancer, including breast, lung, and prostate cancers.
+ A review of 16 clinical studies on selenium and radiotherapy, which included 1303 cancer patients, concluded that selenium supplements improved the general condition of patients, improved their quality of life and reduced the side effects of radiotherapy. Furthermore, selenium supplementation did not reduce the effectiveness of radiotherapy or cause any toxicity.


Oxidative stress and inflammation have been linked to atherosclerosis, or the build-up of plaque in arteries. Atherosclerosis is where our arteries become narrowed, making it difficult for blood to flow through them. It increases the risk of heart attack and stroke. Studies suggest selenium may help keep our heart healthy by reducing inflammation and oxidative stress in our body. For example:

+ A meta-analysis of 25 observational studies found a 50% increase in blood selenium levels was associated with a 24% reduction in the risk of heart disease.
+ A review of 16 controlled studies, involving more than 400,000 people with heart disease, showed taking selenium supplements decreased levels of the inflammatory marker C-reactive protein (CRP) — one of the main risk factors for heart disease.


The leading cause of death in 2022 in the UK was dementia and Alzheimer’s. Oxidative stress is believed to be involved in both the onset and progression of neurological diseases like Alzheimer’s, multiple sclerosis, and Parkinson’s. Studies show that selenium may help prevent mental decline and improve memory loss. For example:
+ A meta-analysis of 6 studies found that selenium supplementation alleviated some of the symptoms of Alzheimer’s disease and Mild Cognitive Impairment.
+ A study analysing metals in the progression of Alzheimer’s disease found patients with Alzheimer’s disease had lower blood levels of selenium.
+ A controlled study examining the long-term effects of antioxidant supplementation on the cognitive performance of 4447 participants found that subjects receiving active antioxidant supplementation (including 100μg of Selenium) had betterepisodic memory scores.


Asthma is associated with increased inflammation, oxidative stress and abnormal immune system function. Some studies suggest that selenium may help reduce asthma-related symptoms due to its role in regulating excessive immune responses and chronic inflammation. For example:

+ A controlled study showed that asthmatic patients had significantly lower concentration levels of blood selenium compared with healthy subjects.
+ A study found that giving people with asthma 200μg of selenium per day reduced their use of the corticosteroid medications used to control their symptoms.

Warning: Whilst selenium is essential for good health, getting too much can be dangerous.  For example, too much selenium causes selenosis, a condition that, in its mildest form, can lead to loss of hair and nails. The NHS advise that an intake of 350μg or less a day of selenium is unlikely to cause any harm. HIMMENSE SHIFT contains 55μg of Selenium (100% NRV).

HIMMENSE SHIFT daily collagen drink has been especially formulated for men and is only 22 Kcal and contains 5.4g of protein. It is also infused with vitamin C, for maximum absorption, as well as vitamins B5, B6, B12D3Ashwagandha and Selenium for multiple health benefits.

HIMMENSE SHIFT a daily hydrolysed Marine Collagen supplement infused with Vitamins C, D, B12, B6, B5 (Pantothenic Acid), Selenium and Ashwagandha that supports physical and mental wellbeing. Benefits associated with the nutrients in HIMMENSE SHIFT range from skin, heart, joint, gut, and sexual health to improved muscle mass and strength. 

At HIMMENSE, we know men want to look and feel their best which is why we’ve made sure our SHIFT collagen protein drink for men is free from added sugar, artificial sweeteners, flavours or colours and does not contain lactose, gluten, dairy, soya, wheat, starch, yeast, animal fat, alcohol, emulsifying agents or soy lecithin. Win win.

Read more Men's Health & Lifestyle blogs from HIMMENSE here

Advice is for information only and should not replace medical care. Consult a doctor or healthcare professional if you have any questions or are taking any other medications before you try any remedies.