{"id":36384,"date":"2026-05-05T16:48:52","date_gmt":"2026-05-05T15:48:52","guid":{"rendered":"https:\/\/jegharkraeft.dk\/?p=36384"},"modified":"2026-05-05T19:57:17","modified_gmt":"2026-05-05T18:57:17","slug":"selenium","status":"publish","type":"post","link":"https:\/\/jegharkraeft.dk\/en\/selenium\/","title":{"rendered":"Selenium and cancer"},"content":{"rendered":"\n<div class=\"wp-block-group alignfull is-style-section-5 has-contrast-color has-base-background-color has-text-color has-background has-link-color wp-elements-b06486e9aa45829c7ad2a4e961c9c15a has-global-padding is-layout-constrained wp-block-group-is-layout-constrained is-style-section-5--2\" id=\"menu\" style=\"margin-top:0;margin-bottom:0;padding-top:var(--wp--preset--spacing--50);padding-bottom:var(--wp--preset--spacing--50)\">\n<div class=\"wp-block-columns alignwide is-layout-flex wp-container-core-columns-is-layout-ca2dd60b wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<h2 class=\"wp-block-heading has-custom-int-link-p-sort-1-color has-text-color has-link-color wp-elements-a867a5e69af727a1b962d2b1d75fb9e7\"><span class=\"ez-toc-section\" id=\"Dietary_Supplements_Grouped_by_Effect\"><\/span><a href=\"https:\/\/jegharkraeft.dk\/en\/kosttilskud-grupperet\/\"><\/a><a href=\"https:\/\/jegharkraeft.dk\/en\/kosttilskud-grupperet\/\">Dietary Supplements Grouped by Effect<\/a><span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Dietary_Supplements_Alphabetical\"><\/span><a href=\"https:\/\/jegharkraeft.dk\/en\/supplements-alphabetically\/\">Dietary Supplements Alphabetical<\/a><span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<h4 class=\"wp-block-heading has-custom-int-link-p-sort-1-color has-text-color has-link-color wp-elements-6a11181498a55b7e2d17e10846556a75\"><a href=\"https:\/\/jegharkraeft.dk\/en\/acai-berries-and-cancer\/\">A,<\/a><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-custom-sort-tekst-color\">.<\/mark> <a href=\"https:\/\/jegharkraeft.dk\/en\/baicalin\/\">B,<\/a><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-custom-sort-tekst-color\">.<\/mark> <a href=\"https:\/\/jegharkraeft.dk\/en\/cats-claw-tomentosa\/\">C,<\/a><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-custom-sort-tekst-color\">.<\/mark> <a href=\"https:\/\/jegharkraeft.dk\/en\/danshen\/\">D,<\/a><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-custom-sort-tekst-color\">.<\/mark> <a href=\"https:\/\/jegharkraeft.dk\/en\/echinacea\/\">E+F,<\/a><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-custom-sort-tekst-color\">.<\/mark> <a href=\"https:\/\/jegharkraeft.dk\/en\/garcinia-cambogia\/\">G,<\/a><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-custom-sort-tekst-color\">.<\/mark> <a href=\"https:\/\/jegharkraeft.dk\/en\/hemp-seeds\/\">H,<\/a><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-custom-sort-tekst-color\">.<\/mark> <a href=\"https:\/\/jegharkraeft.dk\/en\/indol-3-carbinol\/\">I+J+K,<\/a><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-custom-sort-tekst-color\">.<\/mark> <a href=\"https:\/\/jegharkraeft.dk\/en\/lions-mane\/\">L,<\/a><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-custom-sort-tekst-color\">.<\/mark> <a href=\"https:\/\/jegharkraeft.dk\/en\/maitake\/\">M,<\/a><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-custom-sort-tekst-color\">.<\/mark> <a href=\"https:\/\/jegharkraeft.dk\/en\/?p=35837\">N,<\/a><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-custom-sort-tekst-color\">.<\/mark> <a href=\"https:\/\/jegharkraeft.dk\/en\/omega-3\/\">O,<\/a><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-custom-sort-tekst-color\">.<\/mark> <a href=\"https:\/\/jegharkraeft.dk\/en\/peppermint\/\">P,<\/a><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-custom-sort-tekst-color\">.<\/mark> <a href=\"https:\/\/jegharkraeft.dk\/en\/quercetin\/\">Q,<\/a><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-custom-sort-tekst-color\">.<\/mark> <a href=\"https:\/\/jegharkraeft.dk\/en\/reishi\/\">R,<\/a><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-custom-sort-tekst-color\">.<\/mark> <a href=\"https:\/\/jegharkraeft.dk\/en\/selenium\/\"><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-custom-hvid-tekst-color\">S<\/mark>,<\/a><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-custom-sort-tekst-color\">.<\/mark> <a href=\"https:\/\/jegharkraeft.dk\/en\/thc-cannabis\/\">T,<\/a><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-custom-sort-tekst-color\">.<\/mark> <a href=\"https:\/\/jegharkraeft.dk\/en\/vitamin-b\/\">U+V+Z<\/a><\/h4>\n\n\n\n<ul class=\"wp-block-list has-custom-hvid-tekst-color has-text-color has-link-color wp-elements-a6e0008d318186de6fe3ac5fc69d0e0d\">\n<li class=\"has-custom-int-link-p-sort-1-color has-text-color has-link-color wp-elements-712e92408ad5a621520ed682c645d6cc\"><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-custom-baggrund-header-color\">S-adenosylmethionin (SAMe)<\/mark><\/li>\n\n\n\n<li class=\"has-custom-int-link-p-sort-1-color has-text-color has-link-color wp-elements-95b8047517a51389aea7bc67a5cc92e9\"><a href=\"https:\/\/jegharkraeft.dk\/en\/saffron\/\">Saffron<\/a><\/li>\n\n\n\n<li class=\"has-custom-int-link-p-sort-1-color has-text-color has-link-color wp-elements-3cf89715212893b070adc11783bf461a\"><a href=\"https:\/\/jegharkraeft.dk\/en\/sage\/\">Sage<\/a><\/li>\n\n\n\n<li class=\"has-custom-int-link-p-sort-1-color has-text-color has-link-color wp-elements-6364dfd567a60b16f4298ba52f6b836f\"><a href=\"https:\/\/jegharkraeft.dk\/en\/schisandra\/\">Schisandra<\/a><\/li>\n\n\n\n<li class=\"has-custom-int-link-p-sort-1-color has-text-color has-link-color wp-elements-74a016de08fa405f002f5417614b8c6a\"><a href=\"https:\/\/jegharkraeft.dk\/en\/scutellaria-barbata\/\">Scutellaria barbata<\/a><\/li>\n\n\n\n<li class=\"has-custom-her-st-r-du-color has-text-color has-link-color wp-elements-7bda543ee6ae1340f2fd87cee011ef84\"><a href=\"#selenium\">Selenium (scroll down)<\/a><\/li>\n\n\n\n<li class=\"has-custom-int-link-p-sort-1-color has-text-color has-link-color wp-elements-356dee59fabaf19557eb1ab33799e9bc\"><a href=\"https:\/\/jegharkraeft.dk\/en\/serrapeptase\/\">Serrapeptase<\/a><\/li>\n\n\n\n<li class=\"has-custom-int-link-p-sort-1-color has-text-color has-link-color wp-elements-0e85b790e06df91f879b39f9386aa1bc\"><a href=\"https:\/\/jegharkraeft.dk\/en\/shark-liver-oil\/\">Shark Liver Oil<\/a><\/li>\n\n\n\n<li class=\"has-custom-int-link-p-sort-1-color has-text-color has-link-color wp-elements-d47781fbdeb18ed1e254c14688bd4b95\"><a href=\"https:\/\/jegharkraeft.dk\/en\/shiitake\/\">Shiitake<\/a><\/li>\n\n\n\n<li class=\"has-custom-int-link-p-sort-1-color has-text-color has-link-color wp-elements-167341b5627bd615c109a3ac7389a85d\"><a href=\"https:\/\/jegharkraeft.dk\/en\/milk-thistle\/\">Silibinin (Milk thistle)<\/a><\/li>\n\n\n\n<li class=\"has-custom-int-link-p-sort-1-color has-text-color has-link-color wp-elements-102100f7dc5d28b0da00ad9d76fc242f\"><a href=\"https:\/\/jegharkraeft.dk\/en\/spirulina\/\">Spirulina<\/a><\/li>\n\n\n\n<li class=\"has-custom-int-link-p-sort-1-color has-text-color has-link-color wp-elements-5ada372c9662efbc5b8dbae0b1b48f2d\"><a href=\"https:\/\/jegharkraeft.dk\/en\/st-johns-wort\/\">St. John&#8217;s wort<\/a><\/li>\n\n\n\n<li class=\"has-custom-int-link-p-sort-1-color has-text-color has-link-color wp-elements-a1423f36d7e722f85b327e6bd5648dff\"><a href=\"https:\/\/jegharkraeft.dk\/en\/sulforaphane\/\">Sulforaphane<\/a><\/li>\n\n\n\n<li class=\"has-custom-int-link-p-sort-1-color has-text-color has-link-color wp-elements-020125a459a97e41056e8ed5411b0b2c\"><a href=\"https:\/\/jegharkraeft.dk\/en\/gymnema-sylvestre\/\">Sylvestre, Gymnema<\/a><\/li>\n<\/ul>\n\n\n\n<div class=\"wp-block-group has-custom-interne-links-color has-text-color has-link-color wp-elements-a141aae0da29d0267d89e3bd69e2a683 has-global-padding is-layout-constrained wp-block-group-is-layout-constrained\"><\/div>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-vertically-aligned-center is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:50%\">\n<figure class=\"wp-block-image aligncenter size-full is-resized\"><img loading=\"lazy\" decoding=\"async\" width=\"650\" height=\"650\" src=\"https:\/\/jegharkraeft.dk\/wp-content\/uploads\/2025\/02\/bselen.jpg\" alt=\"Selen illustreret ved et gr\u00f8nt pilleglas fra Swanson med p\u00e5skriften Selenium, Antioxidant Support.\" class=\"wp-image-36383\" style=\"aspect-ratio:3\/2;object-fit:cover;width:550px\" srcset=\"https:\/\/jegharkraeft.dk\/wp-content\/uploads\/2025\/02\/bselen.jpg 650w, https:\/\/jegharkraeft.dk\/wp-content\/uploads\/2025\/02\/bselen-300x300.jpg 300w, https:\/\/jegharkraeft.dk\/wp-content\/uploads\/2025\/02\/bselen-100x100.jpg 100w, https:\/\/jegharkraeft.dk\/wp-content\/uploads\/2025\/02\/bselen-600x600.jpg 600w, https:\/\/jegharkraeft.dk\/wp-content\/uploads\/2025\/02\/bselen-150x150.jpg 150w\" sizes=\"auto, (max-width: 650px) 100vw, 650px\" \/><\/figure>\n<\/div>\n<\/div>\n<\/div>\n\n\n\n<div class=\"wp-block-group alignfull is-style-default has-global-padding is-layout-constrained wp-container-core-group-is-layout-b040ace0 wp-block-group-is-layout-constrained has-background\" style=\"margin-top:0;margin-bottom:0;padding-top:var(--wp--preset--spacing--60);padding-right:var(--wp--preset--spacing--20);padding-bottom:var(--wp--preset--spacing--60);padding-left:var(--wp--preset--spacing--20);background-image:url(&apos;http:\/\/jegharkraeft.dk\/wp-content\/uploads\/2025\/02\/bselen.jpg&apos;);background-position:44% 36%;background-size:cover;\">\n<div class=\"gb-element-906497af\">\n<h1 class=\"wp-block-heading\" id=\"selenium\"><span class=\"ez-toc-section\" id=\"Selenium_and_cancer\"><\/span>Selenium and cancer<span class=\"ez-toc-section-end\"><\/span><\/h1>\n\n\n\n<h4 class=\"wp-block-heading\">What is selenium<\/h4>\n\n\n\n<p class=\"wp-block-paragraph\">Selenium is an essential trace mineral, meaning the body needs it in small amounts to function properly. It is found in two forms in the body: organic selenium (selenomethionine and selenocysteine) and inorganic selenium (selenite and selenate). Organic selenium is primarily found in animal products, while inorganic selenium is found in soil and plants.<\/p>\n\n\n\n<h4 class=\"wp-block-heading\">Where selenium is involved<\/h4>\n\n\n\n<p class=\"wp-block-paragraph\">Selenium is involved in the structure of over 25 different selenoproteins, which perform important functions in the body, including:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Antioxidant defense<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Selenoproteins such as glutathione peroxidases protect cells from damage caused by free radicals.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Thyroid function<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Selenium is essential for the production of thyroid hormones.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Immune function<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Selenoproteins are involved in regulating the immune response and fighting infections.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>DNA synthesis and repair<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Selenium plays a role in DNA replication and repair, which is important for preventing mutations and cancer development.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Use\"><\/span>Use<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">In addition to its essential role in the body, selenium has gained increased attention for its potential role in cancer prevention and treatment. Research suggests that selenium may have a number of beneficial effects in connection with cancer, including:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Inhibition of cancer cell division<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Selenium can induce cell death and inhibit proliferation (cell division) in cancer cells.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Promotion of apoptosis<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Selenium can promote apoptosis (programmed cell death) in cancer cells.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Strengthening of the immune system<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Selenium can increase the activity of immune cells that fight cancer.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Reduction of side effects in cancer treatment<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Selenium can protect healthy cells from damage caused by chemotherapy and radiation therapy.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Mechanisms_of_action_and_potential\"><\/span>Mechanisms of action and potential<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Selenium exerts its potential anti-cancer effects through various mechanisms:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Antioxidant effect<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Selenium is an essential component of glutathione peroxidases, a family of enzymes that neutralize free radicals and protect cells from oxidative stress. Oxidative stress can damage DNA and contribute to cancer development.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Immune-stimulating effect<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Selenium can strengthen the immune system by increasing the activity of NK cells (natural killer cells) and T lymphocytes, which play a central role in the body&#8217;s defense against cancer. Selenium can also increase the production of cytokines, signaling molecules that regulate the immune response.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Inhibition of cell proliferation<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Selenium can inhibit the growth and spread of cancer cells by affecting the cell cycle and signaling pathways involved in cell division. For example, it can inhibit the activity of cyclin-dependent kinases (CDKs), which regulate the cell cycle.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Induction of apoptosis<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Selenium can trigger programmed cell death (apoptosis) in cancer cells through various mechanisms, including activation of the caspase cascade and modulation of the Bcl-2 family of proteins. Apoptosis is an important mechanism for removing damaged or abnormal cells, including cancer cells.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Inhibition of angiogenesis<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Selenium can inhibit the formation of new blood vessels (angiogenesis), which is necessary for the growth and spread of tumors. For example, it can inhibit the production of vascular endothelial growth factor (VEGF), a growth factor that stimulates the formation of new blood vessels.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Modulation of DNA repair<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Selenium plays a role in DNA repair processes that can prevent DNA damage that could otherwise lead to cancer. Selenoproteins such as thioredoxin reductases are involved in DNA repair and protect cells from DNA-damaging substances.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Clinical_trials\"><\/span>Clinical trials<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">A number of clinical trials have investigated selenium&#8217;s effect on cancer. Some studies have shown promising results, while others have been less convincing.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>NPC trial (Nutritional Prevention of Cancer trial)<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">This large clinical trial showed that selenium supplementation reduced the risk of prostate cancer, lung cancer, and colon cancer in men. Participants in the study took 200 micrograms of selenium daily in the form of selenomethionine.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">However, the results of clinical trials are not unambiguous, and more research is needed to confirm selenium&#8217;s effectiveness and safety in cancer treatment. Factors such as selenium form, dosage, cancer type, and the patient&#8217;s selenium status can affect the effect of selenium supplementation.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Use_as_a_supplement\"><\/span>Use as a supplement<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Selenium can be taken as a dietary supplement in various forms, including:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Selenomethionine<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">An organic form of selenium that is naturally found in foods and has good bioavailability.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Selenium-enriched yeast<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Another source of organic selenium.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Sodium selenite<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">An inorganic form of selenium.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The recommended daily dose of selenium varies depending on age and gender. For adults, the recommended daily dose in Denmark is 55 micrograms. It is important to follow the recommendations on the product (which are usually somewhat higher) and preferably consult a qualified healthcare provider, especially if you are taking other medication or have a chronic illness.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Benefits_of_selenium\"><\/span>Benefits of selenium<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Essential mineral<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Selenium is an essential mineral that plays an important role in a number of bodily functions, including immune defense, antioxidant defense, and DNA repair.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Potential synergistic effect<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Selenium can potentially enhance the effect of conventional cancer treatment, for example by increasing cancer cells&#8217; sensitivity to chemotherapy or radiation therapy.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Can improve quality of life<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Selenium can contribute to reducing side effects of cancer treatment, such as fatigue, nausea, and hair loss, and improve overall well-being in cancer patients.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Can support the immune system<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Selenium can strengthen the immune system and increase the body&#8217;s ability to fight cancer cells.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Disadvantages_and_limitations\"><\/span>Disadvantages and limitations<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Limited clinical evidence<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">More research is needed to confirm selenium&#8217;s effect on cancer in humans. The results of clinical trials are not unambiguous, and there is uncertainty about optimal dosage and selenium form.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Interactions with medication<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Selenium can interact with certain types of medication, including chemotherapy and radiation therapy. (Studies suggest that intake of selenium together with chemotherapy may allow the dose to be lowered). It is important to inform your doctor about any selenium supplementation.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Side effects<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Too high doses of selenium can cause side effects, such as nausea, diarrhea, hair loss, nail changes, and garlic odor in the breath. It is important to follow the dosage recommendations and not exceed the recommended daily dose.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Not a substitute for conventional cancer treatment<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Selenium should not be used as a substitute for conventional cancer treatment, but can be used as a supplement in consultation with a qualified healthcare provider.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Iodine_selenium_and_hormone_balance\"><\/span>Iodine, selenium and hormone balance<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">There is a complex connection between deficiency of iodine and selenium, the body&#8217;s estrogen levels, and the risk of certain cancers, especially breast and thyroid cancer.<\/p>\n\n\n\n<h4 class=\"wp-block-heading\">Key points<\/h4>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Control of hormones via the thyroid gland:<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Both iodine and selenium are completely crucial for the thyroid gland to function properly. Iodine is used to form thyroid hormones, and selenium helps activate them in the body. Since the two substances work closely together, a deficiency in just one of them can be enough to impair function, so that one can develop low metabolism (hypothyroidism).<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Low metabolism and estrogen:<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>When metabolism is too low, the entire body&#8217;s systems slow down &#8211; including the liver&#8217;s ability to break down and excrete used hormones, including estrogen. This can lead to a condition called &#8220;estrogen dominance,&#8221; where there is a high amount of active estrogen in the body relative to other hormones.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Estrogen and breast cancer:<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>A large proportion of breast cancer cases (approx. 70-80%) are hormone-sensitive, meaning that cancer cells use estrogen to grow. A persistently high level of estrogen is therefore a well-known risk factor, as it can stimulate cells in the breast tissue to divide uncontrollably.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Direct effect in breast tissue:<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Some research also suggests that iodine has a direct protective effect in breast tissue, making cells less sensitive to the influence of estrogen and acting as an antioxidant.<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Conclusion\"><\/span>Conclusion<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Selenium is an essential trace mineral with potential in the fight against cancer. There is evidence that selenium can have beneficial effects on the immune system, quality of life, and treatment outcomes in cancer patients. However, more research is needed to confirm these findings and determine the optimal dosage and use of selenium in cancer treatment.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Selenium should always be used in consultation with a competent healthcare provider, as it can interact with medication and cause side effects at too high doses. It is important to choose quality products from reliable manufacturers and follow the dosage recommendations.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Be aware that selenium is not a miracle cure for cancer. It is a supplement that can support the body and improve quality of life during cancer treatment.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\" id=\"selenium\">Back to <a href=\"https:\/\/jegharkraeft.dk\/en\/supplements-alphabetically\/\" target=\"_blank\" rel=\"noreferrer noopener\">Supplements<\/a><\/p>\n\n\n\n<p class=\"has-custom-menu-links-color has-text-color has-link-color wp-elements-0b01013667400f93702849346fc24830 wp-block-paragraph\"><a href=\"#menu\">(to menu)<\/a><a href=\"https:\/\/jegharkraeft.dk\/en\/supplements-alphabetically\/\"><\/a><a href=\"https:\/\/jegharkraeft.dk\/en\/supplements-alphabetically\/\"><\/a><\/p>\n\n\n\n<h4 class=\"wp-block-heading\">Links<\/h4>\n\n\n\n<p class=\"has-custom-sort-tekst-color has-text-color has-link-color wp-elements-be74c9df6bab3210b213e2955b648a6d wp-block-paragraph\">[1] <a href=\"https:\/\/netdoktor.dk\/vitaminer\/sygdomme\/selen\/\" target=\"_blank\" rel=\"noreferrer noopener\">Selen<\/a> (Netdoktor.dk, 2024) <\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Content: General information about selenium. (Danish Language)<\/li>\n<\/ul>\n\n\n\n<p class=\"has-custom-sort-tekst-color has-text-color has-link-color wp-elements-afb60315cc6d533d50cd66386555eb0c wp-block-paragraph\">[2] <a href=\"https:\/\/sund-forskning.dk\/artikler\/selen-beskytter-mod-kraeft-pa-flere-mader\/\" target=\"_blank\" rel=\"noreferrer noopener\">Selen beskytter mod kr\u00e6ft \u2013 p\u00e5 flere m\u00e5der<\/a> (Sund Forskning, 2017) <\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Content: General information about how selenium protects against cancer in multiple ways. (Danish Language)<\/li>\n<\/ul>\n\n\n\n<p class=\"has-custom-sort-tekst-color has-text-color has-link-color wp-elements-bb13c1514d4fe01ab9d79ad1f5e4df14 wp-block-paragraph\">[3] <a href=\"https:\/\/magasinethelse.dk\/nyheder\/selen-kan-beskytte-mod-kraeft\" target=\"_blank\" rel=\"noreferrer noopener\">Selen kan beskytte mod kr\u00e6ft<\/a> (Magasinet Helse, 2024) <\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Content: General information about how selenium can protect against cancer. (Danish Language)<\/li>\n<\/ul>\n\n\n\n<p class=\"has-custom-sort-tekst-color has-text-color has-link-color wp-elements-73ede1b99197c378b82f5a7ffc7fa196 wp-block-paragraph\">[4] <a href=\"https:\/\/pubmed.ncbi.nlm.nih.gov\/39760958\/\" target=\"_blank\" rel=\"noreferrer noopener\">Study of the effect of zinc oxide, selenium, and silver nanoparticles on the expression level of oxidative stress-associated genes in ovarian cancer<\/a> (PubMed, 2025) <\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Content: In vitro study investigating the effect of zinc oxide, selenium, and silver nanoparticles on the expression level of oxidative stress-associated genes in ovarian cancer.<\/li>\n<\/ul>\n\n\n\n<p class=\"has-custom-sort-tekst-color has-text-color has-link-color wp-elements-fb8a19bea578051220b7a433bc21d60b wp-block-paragraph\">[5] <a href=\"https:\/\/pubmed.ncbi.nlm.nih.gov\/39747357\/\" target=\"_blank\" rel=\"noreferrer noopener\">The anticancer activity of fucoidan coated selenium nanoparticles and curcumin nanoparticles against colorectal cancer lines<\/a> (PubMed, 2025) <\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Content: In vitro study investigating the anticancer activity of fucoidan-coated selenium nanoparticles and curcumin nanoparticles against colorectal cancer cell lines.<\/li>\n<\/ul>\n\n\n\n<p class=\"has-custom-sort-tekst-color has-text-color has-link-color wp-elements-06a5712fc503c3f47ff8aa7f1bc2a0e9 wp-block-paragraph\">[6] <a href=\"https:\/\/pubmed.ncbi.nlm.nih.gov\/39560213\/\" target=\"_blank\" rel=\"noreferrer noopener\">Selenium-containing metallodrug overcomes cervical cancer radioresistance through physical-chemical dual sensitization<\/a> (PubMed, 2025) <\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Content: In vitro study showing that selenium-containing metallodrug overcomes cervical cancer radioresistance through physical-chemical dual sensitization.<\/li>\n<\/ul>\n\n\n\n<p class=\"has-custom-sort-tekst-color has-text-color has-link-color wp-elements-d6e72239d8969b0555ab6634137bbd3f wp-block-paragraph\">[7] <a href=\"https:\/\/pubmed.ncbi.nlm.nih.gov\/37708315\/\" target=\"_blank\" rel=\"noreferrer noopener\">Synthesis and its characterisation of selenium\/silver\/chitosan and cellular toxicity against liver carcinoma cells studies<\/a> (PubMed, 2025) <\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Content: In vitro study investigating the synthesis and characterization of selenium\/silver\/chitosan and cellular toxicity against liver carcinoma cells.<\/li>\n<\/ul>\n\n\n\n<p class=\"has-custom-sort-tekst-color has-text-color has-link-color wp-elements-c4037a27907f684f748f960dca89a6bb wp-block-paragraph\">[8] <a href=\"https:\/\/pubmed.ncbi.nlm.nih.gov\/29489289\/\" target=\"_blank\" rel=\"noreferrer noopener\">Selenium Deficiency<\/a> (PubMed, 2023) <\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Content: Review article on selenium deficiency.<\/li>\n<\/ul>\n\n\n\n<p class=\"has-custom-sort-tekst-color has-text-color has-link-color wp-elements-7cf4eb398f4b5c9c1643d33c60158890 wp-block-paragraph\">[9] <a href=\"https:\/\/pubmed.ncbi.nlm.nih.gov\/40347624\/\" target=\"_blank\" rel=\"noreferrer noopener\">Anticancer signal transduction pathways of selenium nanoparticles in mouse colorectal cancer model<\/a> (PubMed, 2025) <\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Content: In vivo study showing that selenium nanoparticles (SeNPs) naturally accumulate in colon cancer tumors. Here they change the cancer cells&#8217; gene expression, leading to increased anti-inflammatory activity and significant inhibition of both tumor growth and spread (metastasis).<\/li>\n<\/ul>\n\n\n\n<p class=\"has-custom-sort-tekst-color has-text-color has-link-color wp-elements-45c876720111f0e270d24e3dca12e97b wp-block-paragraph\">[10] <a href=\"https:\/\/pubmed.ncbi.nlm.nih.gov\/40024314\/\" target=\"_blank\" rel=\"noreferrer noopener\">Targeting mineral metabolism in cancer: Insights into signaling pathways and therapeutic strategies<\/a> (PubMed, 2025) <\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Content: Review article examining how an imbalance in essential minerals such as copper, iron, zinc, and selenium plays a crucial role in cancer development, as cancer cells have a disturbed metabolism for these substances. This imbalance creates a vulnerability that can potentially be exploited to develop new, targeted treatments and biomarkers for diagnosis.<\/li>\n<\/ul>\n\n\n\n<p class=\"has-custom-sort-tekst-color has-text-color has-link-color wp-elements-a39404f4ed5071aaea2a808962ddf2b6 wp-block-paragraph\">[11] <a href=\"https:\/\/pubmed.ncbi.nlm.nih.gov\/40199010\/\" target=\"_blank\" rel=\"noreferrer noopener\">Synthesis of N-heterocyclic carbene\u2011selenium complexes modulating apoptosis and autophagy in cancer cells: Probing the interactions with biomolecules and enzymes<\/a> (PubMed, 2025) <\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Content: In vitro study showing that new, laboratory-produced substances containing selenium (Selenium-NHC) show strong cell-killing effect against cervical cancer cells. They work by attacking the cancer cell from multiple angles simultaneously, including triggering programmed cell death (apoptosis), disrupting autophagy, and stopping cell division.<\/li>\n<\/ul>\n\n\n\n<p class=\"has-custom-sort-tekst-color has-text-color has-link-color wp-elements-635a2315391b6a82501c5fbd973e1628 wp-block-paragraph\">[12] <a href=\"https:\/\/pubmed.ncbi.nlm.nih.gov\/40273628\/\" target=\"_blank\" rel=\"noreferrer noopener\">Anti-cancer potential of chitosan-starch selenium Nanocomposite: Targeting osteoblastoma and insights of molecular docking<\/a> (PubMed, 2025) <\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Content: In vitro study showing that a newly developed nanoparticle based on selenium and chitosan shows strong and targeted effect against bone tumor cells (osteoblastoma). The particle kills cancer cells by creating destructive oxidative stress and can bind to cancer-specific proteins in bone tissue.<\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<p class=\"has-custom-sort-tekst-color has-text-color has-link-color wp-elements-dd24351491ec780246ab9b28304fc871 wp-block-paragraph\"><strong>Page created:<\/strong> January 12, 2025, Last revised June 9, 2025<\/p>\n\n\n\n<p class=\"has-text-align-center wp-block-paragraph\"><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-custom-menu-links-color\">\u2764<\/mark><\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong><em>What you read on &#8220;Jeg har Kr\u00e6ft&#8221; is not a recommendation. Seek competent guidance.<\/em><\/strong><\/p>\n<\/div>\n<\/div>\n<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_85 counter-hierarchy ez-toc-counter ez-toc-grey ez-toc-container-direction\">\n<div class=\"ez-toc-title-container\">\n<p class=\"ez-toc-title\" style=\"cursor:inherit\">Indhold<\/p>\n<span class=\"ez-toc-title-toggle\"><a href=\"#\" class=\"ez-toc-pull-right ez-toc-btn ez-toc-btn-xs ez-toc-btn-default ez-toc-toggle\" aria-label=\"Toggle Table of Content\"><span class=\"ez-toc-js-icon-con\"><span class=\"\"><span class=\"eztoc-hide\" style=\"display:none;\">Toggle<\/span><span class=\"ez-toc-icon-toggle-span\"><svg style=\"fill: #999;color:#999\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" class=\"list-377408\" width=\"20px\" height=\"20px\" viewBox=\"0 0 24 24\" fill=\"none\"><path d=\"M6 6H4v2h2V6zm14 0H8v2h12V6zM4 11h2v2H4v-2zm16 0H8v2h12v-2zM4 16h2v2H4v-2zm16 0H8v2h12v-2z\" fill=\"currentColor\"><\/path><\/svg><svg style=\"fill: #999;color:#999\" class=\"arrow-unsorted-368013\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"10px\" height=\"10px\" viewBox=\"0 0 24 24\" version=\"1.2\" baseProfile=\"tiny\"><path d=\"M18.2 9.3l-6.2-6.3-6.2 6.3c-.2.2-.3.4-.3.7s.1.5.3.7c.2.2.4.3.7.3h11c.3 0 .5-.1.7-.3.2-.2.3-.5.3-.7s-.1-.5-.3-.7zM5.8 14.7l6.2 6.3 6.2-6.3c.2-.2.3-.5.3-.7s-.1-.5-.3-.7c-.2-.2-.4-.3-.7-.3h-11c-.3 0-.5.1-.7.3-.2.2-.3.5-.3.7s.1.5.3.7z\"\/><\/svg><\/span><\/span><\/span><\/a><\/span><\/div>\n<nav><ul class='ez-toc-list ez-toc-list-level-1 ' ><ul class='ez-toc-list-level-2' ><li class='ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/jegharkraeft.dk\/en\/selenium\/#Dietary_Supplements_Grouped_by_Effect\" >Dietary Supplements Grouped by Effect<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/jegharkraeft.dk\/en\/selenium\/#Dietary_Supplements_Alphabetical\" >Dietary Supplements Alphabetical<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-1'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/jegharkraeft.dk\/en\/selenium\/#Selenium_and_cancer\" >Selenium and cancer<\/a><ul class='ez-toc-list-level-2' ><li class='ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/jegharkraeft.dk\/en\/selenium\/#Use\" >Use<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-5\" href=\"https:\/\/jegharkraeft.dk\/en\/selenium\/#Mechanisms_of_action_and_potential\" >Mechanisms of action and potential<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-6\" href=\"https:\/\/jegharkraeft.dk\/en\/selenium\/#Clinical_trials\" >Clinical trials<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-7\" href=\"https:\/\/jegharkraeft.dk\/en\/selenium\/#Use_as_a_supplement\" >Use as a supplement<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-8\" href=\"https:\/\/jegharkraeft.dk\/en\/selenium\/#Benefits_of_selenium\" >Benefits of selenium<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-9\" href=\"https:\/\/jegharkraeft.dk\/en\/selenium\/#Disadvantages_and_limitations\" >Disadvantages and limitations<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-10\" href=\"https:\/\/jegharkraeft.dk\/en\/selenium\/#Iodine_selenium_and_hormone_balance\" >Iodine, selenium and hormone balance<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-11\" href=\"https:\/\/jegharkraeft.dk\/en\/selenium\/#Conclusion\" >Conclusion<\/a><\/li><\/ul><\/li><\/ul><\/nav><\/div>\n","protected":false},"excerpt":{"rendered":"<p>Dietary Supplements Grouped by Effect Dietary Supplements Alphabetical A,. B,. C,. D,. E+F,. G,. H,. I+J+K,. L,. M,. N,. O,. P,. Q,. R,. S,. T,. U+V+Z Selenium and cancer What is selenium Selenium is an essential trace mineral, meaning the body needs it in small amounts to function properly. It is found in two forms [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":36383,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"inline_featured_image":false,"_lmt_disableupdate":"","_lmt_disable":"","footnotes":""},"categories":[389,375,374],"tags":[],"class_list":["post-36384","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-supplements","category-alternative-treatments","category-treatments"],"modified_by":"Hanne Kj\u00e6r Uhlig","wpml_current_locale":"en_US","wpml_translations":[],"_links":{"self":[{"href":"https:\/\/jegharkraeft.dk\/en\/wp-json\/wp\/v2\/posts\/36384","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/jegharkraeft.dk\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/jegharkraeft.dk\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/jegharkraeft.dk\/en\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/jegharkraeft.dk\/en\/wp-json\/wp\/v2\/comments?post=36384"}],"version-history":[{"count":5,"href":"https:\/\/jegharkraeft.dk\/en\/wp-json\/wp\/v2\/posts\/36384\/revisions"}],"predecessor-version":[{"id":36480,"href":"https:\/\/jegharkraeft.dk\/en\/wp-json\/wp\/v2\/posts\/36384\/revisions\/36480"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/jegharkraeft.dk\/en\/wp-json\/wp\/v2\/media\/36383"}],"wp:attachment":[{"href":"https:\/\/jegharkraeft.dk\/en\/wp-json\/wp\/v2\/media?parent=36384"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/jegharkraeft.dk\/en\/wp-json\/wp\/v2\/categories?post=36384"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/jegharkraeft.dk\/en\/wp-json\/wp\/v2\/tags?post=36384"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}