Selenium May Not Reduce the Risk for Heart Disease

A new study suggests that selenium supplementation may not reduce the risk of heart disease.

Selenium is an essential trace mineral found in soil, water and some foods. It is a component of the amino acids cysteine and methionine. Selenium is required for functioning of the body's antioxidant enzymes and for cell growth and survival.

The presence of selenium in locally grown food and selenium levels in human populations reflects the selenium levels in local soil. The selenium content in food is influenced by geographical location, seasonal changes, protein content and food processing. Periodic monitoring of selenium levels in soil and food is necessary. Selenium supplements may benefit people living in regions with very low environmental levels of selenium.

In a recent study, researchers conducted a comprehensive literature search for well-designed clinical trials evaluating the effects of selenium supplementation on heart disease, death, diabetes and changes in heart disease risk. Twelve studies evaluating 19,715 individuals were ultimately identified for inclusion.

The researchers found that selenium supplementation may not have a significant effect on the risk for death, death caused by heart disease, non-fatal heart disease-related events and all heart disease-related effects. Adverse effects related to selenium supplementation included hair loss and dermatitis. The authors noted that selenium supplementation reduced total cholesterol; however, the reductions were not significant. Furthermore, supplementation was linked to a slight increased risk for diabetes; however, this result was also not significant.

The authors concluded that there is a lack of supportive evidence to suggest that selenium supplementation may reduce the risk for heart disease. Further research is warranted.

In addition to selenium, several other integrative therapies have been studied for their potential to reduce heart disease risk. Early studies in animals and humans suggest that diets containing chia seed may decrease risk factors for cardiovascular disease (CVD). Evidence suggests that the benefits of Salba® in humans are similar to those of other whole grains. Further study is needed.

For more information about integrative therapies with evidence of benefit of heart disease prevention, please visit Natural Standard's Comparative Effectiveness Database.

For more information about selenium, please visit Natural Standard's Foods, Herbs & Supplements Database.

Comments

[Amber]

I'm surprised just hearing that Selenium was even used as a supplement for heart disease. The things you learn from this blog (even indirectly)! When looking briefly at the Selenium monograph on Natural Standard, there's a host of uses that have evidence grades. I think the only one that stood out to me as familiar was it's use in Dandruff. I remember seeing it as an ingredient in a shampoo before. But even so, it has an evidence grade of C for use in dandruff.

[ML]

It seems like Selenium does not have any effect on the risk for heart disease. I am not that familiar with Selenium. The adverse effects are quite unfavorable. Looking at the bottom line monograph, Selenium has a grade of B for prostate cancer prevention. It seems that there needs to be a better designed study to confirm the lack of cardiovascular benefit of Selenium. It will be interesting to see if other uses of Selenium will be discovered since it is a trace element that is commonly found in soil.

[Zach]

I remember selenium being one of the minerals that needs to be supplemented when patients are on total parenteral nutrition (TPN) for extended periods, so one would assume that there is at least reason for not being deficient.
I found myself wondering what foods had selenium in them. Here's a nice table from the NIH
http://ods.od.nih.gov/factsheets/Selenium-HealthProfessional/
Holy Brazil nuts!

[SB]

I had not ever heard of selenium being used to prevent heart disease. I would think the best things to prevent heart disease would be plain old diet and exercise. But I find it interesting that our selenium intake coresponds with the amount of selenium in the soil.

[MS]

According to the Natural Standard website, the professional monograph, selenium has around 50 common or studied uses. It has an evidence grade of B (Good Scientific Evidence) for Keshan disease, prostate cancer prevention and as an antioxidant. The rest of it's uses are mostly grade C(Unclear or Conflicting Scientific Evidence) and a few grade D (Fair Negative Scientific Evidence). I would be interested to know if in areas that have higher selenium content in their soil the incidence of Keshan disease and prostate cancer are lower.

[bz]

I wonder what regions are known to have more selenium in their soil, and if selenium deficiency is really reflective of regional selenium deficiency in soil anymore. The amount of vegetables and fruits shipped from out of state is staggering these days. I can't imagine that localized selenium deficiency in humans definitely reflects low soil levels in that area.

[a]

Selenium is one of the supplements that you don't hear too much about so this was a nice summary. I think the adverse effects of hair loss and dermatitis would scare off a lot of people from using this supplement even if they did find a cardiovascular benefit. I read on the Natural Standard monograph Selenium has been found to be beneficial for high cholesterol but at high (and therefore possibly unsafe) concentrations.

[AR]

Results from this trial concluded that the available information does not support the use of selenium to prevent cardiovascular disease, but this topic may need further research. One of the trials reviewed in this article found that selenium supplementation decreased non-HDL cholesterol, which was statistically significant.

[bz]

While the findings of this analysis are interesting, I did not realize selenium was ever thought to have major effects on the heart. As a necessary nutrient in the processing of antioxidants, I thought it would be more important in the prevention of cancer than heart disease. While it should not be eliminated from the diet, I suppose it reinforces the point that it should not be used alone to treat heart disease.

[bz]

While the findings of this analysis are interesting, I did not realize selenium was ever thought to have major effects on the heart. As a necessary nutrient in the processing of antioxidants, I thought it would be more important in the prevention of cancer than heart disease. While it should not be eliminated from the diet, I suppose it reinforces the point that it should not be used alone to treat heart disease.