Selenium Status and Mortality Risk

Mortality and morbidity. As we get older, we start to think about ways to reduce the risk of an early death. We want to reduce the risk of living out our lives in ill health.

Zion National Park in the USA
Pictured here: A creek in the Zion National Park in Utah.

We think about diet, exercise, 10,000 steps a day, hobbies, social contact. But, do we think about our selenium intake and status? Now, some large survey studies conducted in the US have shown that higher selenium status is significantly associated with lower mortality.

Each year, the National Health and Nutrition Examination Survey (NHANES) in the United States conducts surveys that focus on different population groups or health topics. This week, we present data from studies of selenium status and mortality.

Selenium Status and Type 2 Diabetes

Qiu et al examined the data from 3199 adults with type 2 diabetes. Their analysis showed that higher serum selenium concentrations are associated with lower all-cause mortality and lower heart disease mortality among individuals with type 2 diabetes [Qiu 2022]. read more

Selenium-Enriched Yeast Supplementation Studies

The rationale for taking a selenium-enriched yeast preparation: one or more of the selenium compounds in the preparation other than selenomethionine may be the selenium species that has specific effects against cancer. This is an area for further research.

Glass of beer made using brewer's yeast
Selenium-enriched yeast preparations use Saccharomyces cerevisiae, commonly known as as brewer’s yeast. The yeast is grown in a selenium-enriched medium in which the yeast absorbs the selenium. The finished preparation is pasteurized, causing the yeast cells to die. Selenium-enriched yeast preparations contain many organic selenium compounds in addition to selenomethionine.

This week, we focus on studies conducted with a selenium-enriched yeast preparation containing at least 20 different species of selenium in addition to selenomethionine [Bendahl & Gammelgaard 2004].

Randomized, double-blind, controlled clinical trials are the gold standard method for testing the safety, absorption, and efficacy of nutritional supplements and medical drugs. Below, we summarize some of the important clinical trials of nutritional interventions using selenium-enriched yeast. read more

Selenium and Toxic Metals and the Ageing Kidney

In individuals older than 50-60 years, the kidneys’ glomerular filtration rate decreases with increasing age. The glomerular filtration rate is a measure of how well your kidneys are working. In your kidneys, there are tiny filters (called glomeruli) that remove waste and excess fluid from the blood.

Jan Aaseth
Jan Aaseth is a Norwegian physician and professor who has done extensive research in endocrinology, toxicology, and medical biochemistry. Here we summarize his review of the relationship between selenium status, heavy metal toxicity, and the kidneys.

Exposure to toxic metals – mercury, cadmium, lead – can be detrimental to kidneys of normal adults. Accordingly, exposure to toxic metals can affect individuals with reduced glomerular filtration rates even more adversely.

Professor Jan Aaseth and a team of researchers have reviewed the available research data. Their findings show the following relationships [Aaseth 2021]:

Elderly Individuals More Susceptible to Toxic Metal Exposure

Healthy elderly individuals are capable, for the most part, of maintaining normal kidney function. However, especially after the age of 70 years, physiological changes occur in the kidneys. read more