Selenium ptroects against hazardous environmental toxins

Everybody is exposed to heavy metals and other environmental toxins. They are present in the water, the air, our diet, in cosmetics, tobacco smoke, medicine, and countless other sources. These toxins increase our risk of cancer, neurological disorders, thyroid disease, autoimmune disease, and numerous other health problems. Also, the combination of different toxins causes a “cocktail effect” that we know very little about. According to a Spanish study of mice, which is published in Science of The Total Environment, a selenium-enriched diet has a protective effect.

The new study was conducted at the Cordobas University in Spain. To begin with, the researchers looked at how environmental toxins such as mercury, cadmium, arsenic, and widely used painkillers and antibiotics (diclofenac and flumequine) affected the liver function in mice. All these heavy metals and toxins are widespread in our environment and tend to accumulate throughout the food chain, which leaves us humans vulnerable to their harmful impact.
The different toxins have one thing in common: They cause oxidative stress in the body. Oxidative stress is when harmful free radicals outnumber the protective antioxidants and initiate chain reactions where they attack healthy cells and tissues. This increases the risk of reduced IQ, impaired immune function, chronic fatigue, difficulty with concentration, headache, leukemia, Alzheimer’s disease, Parkinson’s disease, thyroid disorders, and other health problems.
By studying the mice, the scientists could see how the combination of the five specific toxins caused a particularly worrying “cocktail effect”. Not only did the result in increased oxidative stress, it also had an impact on 275 different proteins that are related to liver function. In addition, the scientists observed disturbances in the lipid and carbohydrate metabolism of the mice plus increased concentrations of proteins related to stress response and inflammation. It’s a fact that oxidative stress and chronic inflammation are related to a majority of chronic ailments. The presence of oxidative stress and metabolic disturbances was substantially greater in mice that were exposed to the cocktail of environmental pollutants compared with mice that were exposed to individual heavy metals or medical substances. In other words, it is much worse when we are exposed to many different toxins at the same time.

Does selenium offer hope?

The researchers wanted to find out if selenium supplementation could counteract oxidative damage caused by the different toxins, so they supplemented a third of the mice. Selenium supports a variety of different antioxidants, especially the powerful GPX antioxidant that scavenges free radicals and counteracts chronic inflammation. Also, selenium supports a host of selenium-dependent enzymes (selenoproteins) that are important for cellular energy turnover, immune defense, thyroid function, cancer protection, etc.
They found that mice on a selenium-supplemented diet had significantly fewer pathological changes in their liver function compared with non-supplemented mice. The researchers assume that selenium supplementation can reduce oxidative stress and prevent liver damage caused by exposure to environmental toxins. Previous studies have demonstrated that selenium reacts with mercury and forms an inert compound called mercury selenide, which the body can excrete. That way, selenium has a protective effect.

How do get enough selenium?

Selenium is found in fish, offal, meat, eggs, wholegrains, Brazil nuts, and several other foods. The agricultural soil in Europe, however, is low in selenium and that affects the entire food chain. It can be a challenge to get enough selenium from your daily diet because of this. The above-mentioned study and other studies suggest that exposure to environmental toxins increases the need for selenium for antioxidant protection and for carrying out all its other functions in the body. Remember, the selenium that binds to mercury is no longer available to form selenoproteins and that shortage must be compensated for.
One of the selenoproteins, selenoprotein P, is commonly used as a marker of the blood’s selenium status. It takes around 100 micrograms of selenium daily to properly saturate this selenoprotein. An ever higher selenium intake is required to effectively rid the body of heavy metals and other environmental toxins. According to the European Food Safety Authority (EFSA), the safe upper intake level for selenium is 300 micrograms per day.

References:

Paula V. Huertos-Abril et al. Proteomic analysis of the hepatic response to a pollutant mixture in mice. The Protective action of selenium. Science of The Total Environment. 2023

Jing Huang et al. Selenium Status and Its Antioxidant Role in Metabolic Diseases. Oxidative Medicine and Cellular Longevity. 2022

Michael Gochfeld, Joanna Burger. Mercury interactions with selenium and sulfur and the relevance of SE: HG molar ratio to fish consumption advice. Environ Sci Pollut res Int. 2021

Rosewell Timmerman, Stanley Omaye. Selenium´s Utility in Mercury Toxicity: A Mini-Review. Scientific Research. 2021