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Selenium supplement benefits and dosage

What is selenium good for, which foods contain it, and do you need a supplement?

Sophie Medlin
Sophie Medlin
Head of Nutritional Research
March 10, 2020
4 min read

Present in large quantities in Brazil nuts but little else, selenium is one of the essential minerals that we all need. In this summary, we’ll look at the benefits of selenium, along with examples of other selenium-rich foods, and the symptoms of a deficiency.

What is selenium?

While selenium is vital for several key processes in the body, it has recently garnered more attention as an antioxidant, helping to protect cells from damage. This recent attention has led to more research being conducted, so we’re still discovering things about the benefits of selenium.

We only need small amounts of selenium, but as we can’t produce any of it ourselves, we need to get it from external sources—predominantly our food.

Should I be taking a selenium supplement?

The nutrient reference value (NRV) is 55mcg per day. Most people can get this from a balanced diet, but a supplement can be helpful to ensure you get the full amount every day. And to make it simple, every dose of the Heights Smart Supplement contains 55mcg (equal to 1 Brazil nut or a tin of sardines) so 100% of your needs. It’s recommended that you don’t exceed 350mcg of selenium a day.

Which foods contain selenium?

Brazil nuts are famous as a selenium-rich food, and for good reason. While the exact content can vary based on the quality of the soil it was grown in, on average you can get the full NRV from one Brazil nut. However, there are other examples of selenium-rich foods, including:

  • Tuna

  • Sardines

  • Offal

  • Prawns

  • Cottage cheese

For those following a vegan diet, there are other plant-based sources of selenium but higher quantities will need to be eaten to reach the daily required amount:

  • Sunflower seeds

  • Green or brown lentils

  • Cashew nuts

What are the benefits of a selenium supplement?

There is still a lot of ongoing research into the effects of selenium, and the full extent of its benefits. However, we do know that it contributes to:

  • Healthy function of the immune system

  • DNA synthesis

  • Production of thyroid hormones

  • Normal reproductive function

Selenium’s powerful antioxidant properties can help to prevent cell damage and oxidative stress caused by free radicals. Reducing oxidative stress can protect against cognitive decline, which can lead to Alzheimer’s and mood disorders such as depression.

What are the symptoms of a selenium deficiency?

Serious selenium deficiencies are rare, although certain groups are at higher risk than others..Not getting enough can lead to an increased risk of heart disease, male infertility, and arthritis.

A study on young adults also found that low or excessively high blood levels of selenium resulted in higher risk of depressive symptoms than in people with healthy levels.

How we use selenium in the Smart Supplement

We've designed the Heights Smart Supplement with selenium from sodium selenate, so that your brain gets all the benefits. You can be sure that:

  • Each dose contains 100% of the NRV for selenium.

  • Our selenium is pure and quality-tested.

  • Everything is manufactured in small batches.

  • It meets many common dietary and lifestyle practices: It's gluten-free, 100% plant-based, allergen-free and contains absolutely zero GMOs, contaminants, fillers or colourants.

Our formula

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Here’s a handful of relevant scientific studies on selenium.

  • Conner, T. S., Richardson, A. C., & Miller, J. C. (2015). Optimal serum selenium concentrations are associated with lower depressive symptoms and negative mood among young adults. The Journal of nutrition, 145(1), 59-65.

  • de Wilde, M. C., Vellas, B., Girault, E., Yavuz, A. C., & Sijben, J. W. (2017). Lower brain and blood nutrient status in Alzheimer's disease: Results from meta-analyses. Alzheimer's & Dementia: Translational Research & Clinical Interventions, 3(3), 416-431.

  • Cardoso, B. R., Apolinário, D., da Silva Bandeira, V., Busse, A. L., Magaldi, R. M., Jacob-Filho, W., & Cozzolino, S. M. F. (2016). Effects of Brazil nut consumption on selenium status and cognitive performance in older adults with mild cognitive impairment: a randomized controlled pilot trial. European journal of nutrition, 55(1), 107-116.

  • Berr, C., Arnaud, J., & Akbaraly, T. N. (2012). Selenium and cognitive impairment: A brief‐review based on results from the EVA study. Biofactors, 38(2), 139-144.

  • Santos, J. R., Gois, A. M., Mendonça, D. M., & Freire, M. A. (2014). Nutritional status, oxidative stress and dementia: the role of selenium in Alzheimer's disease. Frontiers in aging neuroscience, 6, 206.

  • Smorgon, C., Mari, E., Atti, A. R., Dalla Nora, E., Zamboni, P. F., Calzoni, F., ... & Fellin, R. (2004). Trace elements and cognitive impairment: an elderly cohort study. Archives of Gerontology and Geriatrics, 38, 393-402.

  • Slawinska, K., Bielecka, G., Iwaniak, K., Wosko, S., & Poleszak, E. (2017). Selenium and manganese in depression–preclinical and clinical studies. Current Issues in Pharmacy and Medical Sciences, 30(3), 151-155.

We also used these sources when writing this article:

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