Selenium is one of the most important components of the body’s antioxidant system, protecting the body against oxidative stress.
It is considered a trace mineral which doesn’t require large doses, but yet it is essential for optimal health. Selenium pairs up with vitamin E to become a more powerful antioxidant within the body. It is vital to the proper functioning of the thyroid gland. It works alongside vitamin C, helping to strengthen the body’s immune system, and an important ingredient to create the body’s master antioxidant called glutathione.
Let’s take a glance at a number of the scientifically proven ways in which this powerful mineral protects our health.
- Thyroid Health:
The thyroid gland mainly produces T4 and T3 hormones. T3 is the active form. Hence T4 needs to be converted into T3 for it have the required impact on the body. When our body runs low on selenium, it cannot convert T4 into T3, which may cause a condition of low thyroid or hypothyroidism. Selenium is also needed for the synthesis of thyroperoxidase (TPO) enzyme. This enzyme is essential for production of T4. Hence lack of selenium impacts both, the production of T4 and conversion into T3.
The main symptoms of Hypothyroidism are weight gain, loss of energy, hair loss, facial puffiness, poor metabolism, anemia etc. In other words, a slow thyroid can mean slow anything and everything in the body! Supplementing with selenium can be useful in situations where sufficient T4 is not being produced or conversion of T4 to T3 is not happening.
Thus, supplementing with selenium can help reverse or reduce the hypothyroid symptoms and move the system towards an euthyroid state.
- A Powerful Antioxidant
Antioxidants are powerful compounds in foods that lower inflammation, act as anti-aging agents, protect our DNA, and fight free radicals in our bodies.
High oxidative stress can lead to chronic diseases like cardio-vascular ailments, strokes, cancer, alzheimer’s and other chronic and degenrative diseases. Foods and supplements with selenium work wonders to combat oxidative stress and protect the body.
Coming back to the thyroid gland, the production of thyroid hormones also results in the production of H2O2 (hydrogen peroxide) which is a highly oxidising substance. Presence of sufficient selenium is key to protecting the thyroid tissues from the potential oxidation due the H2O2.
- Prevents Cancer:
Even in trace amounts, selenium wields amazing power preventing and fighting cancer. There is a robust correlation between levels of selenium within the blood and therefore the risk of certain cancers. DNA mutations are understood to be the main cause behind many cancers. Once again oxidative stress is the main cause leading to DNA damage and hence mutations. When DNA is damaged, cells may turn cancerous.
Selenium being a powerful antioxidant, helps protect the DNA from oxidative damage, leading to reduced chances of cancer.
- Heart Health:
Atherosclerosis (build up of plaque inside the arteries) is the main cause of heart related issues. This buildup of plaque happens when the body tries to repair the damage caused by high levels of inflammation. As we already know, selenium lowers inflammation within the body which helps lower the likelyhood of plaque build-up leading to clogged cardiac arteries.
Incorporating selenium-rich foods into our diet may be a good way to stay away from oxidative stress and keep inflammation to a minimum. Selenium’s powerful antioxidant properties protect against heart diseases and strokes.
- Powers up the Immune System:
Our immune systems perform a variety of life-preserving functions such as fighting off deadly bacteria, viruses, fungi etc. by fighting back infection and helping to heal wounds on the body as well. When the immune system goes awry, it can become overactive and attack the body, which can lead to autoimmune disease flare ups. Selenium’s antioxidant property lowers inflammation and protects the immune system by lowering oxidative stress. Deficiency of Selenium reduces the immune response to infections. Patients who are struggling with more serious infections like influenza A, tuberculosis and hepatitis C also can benefit selenium supplements.
- Improves Asthma
Asthma is an inflammatory response to allergens. When bronchial tubes become inflamed, they constrict or spasm causing coughing, wheezing, and extreme shortness of breath. This can also become a life-threatening condition.
Most common medical treatment for asthma is corticosteroid inhalers that help dampen the inflammatory response and assist in opening up airways. It has many side effects and long term use is surely not good for health. Since asthma is related to high levels of oxidative stress and inflammation, selenium helps to reduce these symptoms and frequecy of attacks.
- Boost Fertility:
Selenium supplementation also has a positive effect on testosterone levels, it increases sperm motility and blood flow, two important components for conception. Selenium is also found within the sperm mitochondria and may affect the behaviour and proper function of sperm as they move through the vagina to fertilize an ovum. For women, it’s thought that selenium can help to reduce the chance of miscarriage during initial stages of pregnancy.
Daily Recommendation & Toxicity of Selenium:
The recommended daily dose of Selenium is 55mcg for normal adults. Pregnant & breastfeeding mothers could consume 60-70mcg per day.
The upper limit for the optimal level of selenium for adults is 400 mcg. It is rare for anyone to overdose on selenium.
However, the risk of selenium toxicity is increased when this powerful antioxidant is introduced in the form of supplementation. Those who are on regular selenium supplementation need to keep an eye on their dietary selenium intake.
Very high doses of selenium are not advised as they may cause issues such as fatigue, nausea, vomiting, brittle nails, skin rash, muscle soreness, kidney or heart failure and even death too.
Food sources of selenium:
Selenium is easily found in whole grains and few animal products such as fish and eggs. To add more of this powerful antioxidant to your diet, the following foods are recommended –
- Brazil Nut
- Sunflower seeds
- Tuna
- Sardines
- Fortified bread
- Brown rice
selenium may be a trace mineral, but it surely has far greater than a ‘trace’ effect on our all-round health and wellbeing. It has multiple positive health benefits. People can get selenium from supplements in the short term. However, in the long term, it is better to ensure optimum levels via food sources.
References:
https://www.sciencedirect.com/science/article/abs/pii/S0140673600024909
https://www.hsph.harvard.edu/nutritionsource/selenium/
https://www.researchgate.net/publication/7630279_Selenium_and_the_Control_of_Thyroid_Hormone_Metabolism
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5307254/
