Selenium: Benefits, Uses, Side Effects, Dosage, and More

Health Notice: This article was written using the Consensus AI Academic Search Engine. It is intended solely for informational purposes and should not be considered medical advice. Always consult a licensed healthcare provider for diagnosis, treatment, or medical guidance. Please refer to the full Disclaimer at the end of this article.

Selenium is a vital nutrient with numerous health benefits, including antioxidant properties, cancer prevention, and improved glucose metabolism. However, it is essential to adhere to recommended dosages to avoid potential side effects and toxicity. Further research is needed to fully understand the long-term effects of selenium supplementation, particularly at higher doses.

Selenium is an essential trace element that plays a crucial role in various bodily functions, including antioxidant defense, thyroid hormone metabolism, and immune function. It is naturally found in soil, water, and some foods. This article explores the benefits, uses, side effects, and recommended dosages of selenium, drawing on recent scientific research.

Benefits of Selenium

Antioxidant Properties

Selenium is a key component of selenoproteins, which have antioxidant properties that help protect cells from damage caused by free radicals. This can reduce oxidative stress and may lower the risk of chronic diseases such as cancer and cardiovascular disease1 2 4.

Cancer Prevention

Several studies have investigated selenium’s role in cancer prevention. For instance, selenium supplementation has been shown to reduce the recurrence of advanced colorectal adenomas, which are precursors to colorectal cancer3. Additionally, selenium may improve the quality of life and reduce side effects in cancer patients undergoing chemotherapy6.

Glucose Metabolism

Selenium supplementation has demonstrated beneficial effects on glucose metabolism, particularly in pregnant women with gestational diabetes mellitus (GDM). It has been shown to significantly reduce fasting plasma glucose and serum insulin levels, as well as improve insulin sensitivity2.

Immune Function

Selenium is known for its immunomodulatory properties, which can enhance the body’s immune response. This is particularly beneficial for individuals undergoing treatments that weaken the immune system, such as chemotherapy6.

Uses of Selenium

Dietary Supplement

Selenium is commonly used as a dietary supplement to prevent selenium deficiency, which can lead to various health issues, including weakened immune function and cognitive decline. It is available in several forms, including selenomethionine, selenocysteine, and selenium-enriched yeast7.

Chemoprevention

Selenium is used in chemoprevention to reduce the risk of certain cancers. For example, it has been studied for its potential to prevent lung cancer in patients with resected non-small-cell lung cancer (NSCLC)8.

Management of Chronic Conditions

Selenium supplementation has been explored for its potential benefits in managing chronic conditions such as type 2 diabetes and cardiovascular diseases. However, the results are mixed, with some studies indicating an increased risk of type 2 diabetes with long-term selenium supplementation5 10.

Side Effects of Selenium

Toxicity

High doses of selenium can lead to toxicity, characterized by symptoms such as gastrointestinal distress, hair loss, and nail changes. In severe cases, it can cause liver and kidney damage1 7. A study on high-dose selenium supplementation in prostate cancer patients reported more selenium-related side effects at higher doses, although no serious toxicities were observed1.

Increased Risk of Type 2 Diabetes

Long-term selenium supplementation has been associated with an increased risk of type 2 diabetes, particularly at higher doses. This was observed in studies where participants were given selenium supplements for extended periods5 10.

Other Side Effects

Other potential side effects of selenium supplementation include nausea, fatigue, and changes in liver and kidney function. These side effects were noted in studies involving cancer patients and individuals undergoing chemotherapy6 9.

Recommended Dosage

General Population

The recommended dietary allowance (RDA) for selenium varies by age, sex, and life stage. For most adults, the RDA is 55 micrograms per day. However, the tolerable upper intake level (UL) is set at 400 micrograms per day to avoid toxicity1.

Specific Conditions

For specific conditions such as cancer prevention or management of GDM, higher doses may be used under medical supervision. For example, a study on GDM used a dose of 200 micrograms per day, which showed significant benefits without adverse effects2. However, doses exceeding 300 micrograms per day have been associated with increased mortality and should be avoided10.

Disclaimer

The content in this blog post was generated using Consensus, an AI-powered academic search engine, and is based on publicly available scientific literature. While we strive to provide accurate, up-to-date, and well-researched information, this content is intended for informational and educational purposes only.

It does not constitute medical advice, diagnosis, or treatment. Always consult a qualified healthcare professional before making decisions related to any medical condition, treatment, or medication.

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Use of this information is at your own risk. Where provided, citations link to original scientific studies for reference only—these should be reviewed independently and interpreted with the support of a qualified medical or research professional.

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