How Selenium-Rich Foods Boost Thyroid And Heart Health
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It’s likely that most of us have not heard of selenium. And yet, it plays an important part in sustaining the functions of some major systems in the body, such as the endocrine, immune, and cardiovascular systems. Notably, the thyroid, which is part of the endocrine system, contains the highest amount of selenium compared to other organs. 

Selenium is a powerful micronutrient. It is known to be a powerful antioxidant, responsible for countering excess free radicals in the body. One review of 69 studies covering more than 350,000 individuals revealed that having an elevated concentration of selenium in the bloodstream is correlated with a lower likelihood of various kinds of cancer, such as lung, breast, colon, and prostate cancer. Studies have also shown that selenium reduces the risk of heart disease by reducing inflammation and oxidative stress. Selenium is particularly important for maintaining thyroid health. Selenium deficiency has been associated with thyroid conditions like Hashimoto’s thyroiditis, a type of hypothyroidism in which the immune system attacks the thyroid gland. Additionally, new research shows that a multivitamin plus selenium may slow the progression of HIV in people who don’t have access to antiretroviral drugs.  

Recent studies have pointed to the possibility of a link between selenium deficiency and certain types of cancer, but further research is necessary. A 2020 research study suggested that selenium insufficiency might affect cognitive functioning as well. On the other hand, some research has produced contrasting results, so further studies are required in this field. Along with living in an area that has low levels of selenium in the soil, there are several factors that can increase the likelihood of suffering from selenium deficiency. These include going through dialysis, having HIV, and having a digestive complaint such as Crohn's disease. All of these can impede the body's ability to take in selenium, even if the necessary amount is present in the diet. A deficiency of selenium, while rare, can lead to a variety of signs and symptoms, which include male and female infertility, muscle fatigue, tiredness, confusion, alopecia, and an impaired immune system. 


Fortunately, the best way to combat selenium deficiency is by eating selenium-rich foods. Some of the best sources include: 

1.    Oysters: 238% of the daily value (DV) in 3 ounces (85 grams) can be obtained through oysters, among the best sources of selenium. Fancy up your dinner with an oyster plate or try out this recipe for a delicious oyster stew.

2.    Brazil nuts: These are little pockets of great nutrition packed with vitamins and antioxidants. 174% of the DV in one nut (5 grams) can be obtained through these nuts. You can incorporate Brazil nuts as part of your evening snack via Brazil nut banana bread. 

3.    Fish like yellowfin tuna, sardines, and halibut: among these, halibut is the richest source of selenium, followed by tuna and sardines. Here is an option to cook halibut with Indian spices.

4.    Sunflower seeds: Sunflower seeds are an extremely popular and healthy snack. 27% of the DV in 1 ounce (28 grams) is the amount of selenium you can derive from sunflower seeds. Here are some ways you can incorporate sunflower seeds into your diet. We are particularly partial to the risotto.   

5.    Shiitake mushrooms and eggs: You can derive more than half of your daily selenium requirements with just two eggs. Go ahead, make a healthy breakfast of two eggs and a side of sauteed shiitake mushrooms, and make it a happy day for your heart and your thyroid.  

Selenium supplements are rarely ever required but are prescribed in some cases, like in HIV. But one needs to be cognizant of selenium toxicity as well. Consuming very high doses of selenium can be toxic and even fatal. The RDA for selenium is 55 mcg per day, with an upper limit of 400 mcg per day.

Here's a great bread you can make at home using Brazil nuts, one of the best sources of selenium. 

Banana bread with Brazil nuts


    100 ml of sunflower oil, plus extra for greasing 

    150g caster sugar 

    150g plain flour 

    150g Brazil nuts, roughly chopped 

    50g desiccated coconut 

    1 tbsp butter, diced 

    2 large, overripe bananas  

    1 large egg, plus 1 large egg white 

    5 tbsp milk 

    ½ tsp baking powder 

    ¼ tsp ground cinnamon 



Heat the oven to 180 degrees C. Grease a 900-gram loaf tin, then line the base and ends with a long strip of baking parchment. Stir together 2 tablespoons each of the sugar, flour, nuts, and coconut. Add the butter and rub together to make sticky crumbs. Set aside. 


Mash the bananas well, then stir in the sunflower oil, egg, and milk. In a separate large bowl, mix half of the remaining sugar, followed by the remaining flour, nuts, and coconut, then the baking powder and cinnamon. 


Whisk the egg whites to stiff peaks, add the final bit of sugar, and whisk again until stiff and shiny. Stir the banana mixture into the dry ingredients, then lightly fold in the egg white mixture. Gently scrape into the tin and scatter over the crumb mixture. 


Bake for 40 minutes or until a skewer poked in comes out clean, covering with foil if the bread starts to go too brown. Cool in the tin, then remove and thickly slice, eating with butter, if you like.