The novel coronavirus, which is the cause of COVID-19, is just the latest of a number of disease-causing viruses to apparently spring forth from China.
In 1957 China gave us the Asian flu. Then in 1968, the Hong Kong flu killed about one million people. In 2003, Guangdong, China was the birthplace of SARS - Severe Acute Respiratory Syndrome caused by a coronavirus. Most recently, in late 2019, the novel coronavirus began causing disease in Wuhan, China. This is the cause of COVID-19, that we are dealing with now.
What is it about China and viruses? Keshan disease may provide the answer.
Keshan disease is the name given to a juvenile cardiomyopathy (heart disorder) endemic to Keshan county and, actually, large areas of 14 out of the 23 provinces in China. Deficiency of the essential trace mineral selenium seems to be a contributing factor to Keshan disease. Much of China has very low levels of selenium in the soil. Therefore, the food grown in the soil is low in selenium. The animals and humans that eat these foods are lacking in selenium. In the regions with greater incidence of Keshan disease the corn was found to have less selenium and hair analysis found the residents to have lower selenium levels.
It has also been found that people with Keshan disease have higher levels of antibodies to Coxsackie virus. Selenium deficiency and viral infection together seem to result in Keshan disease.
What’s the relationship between selenium deficiency, Coxsackie virus, and cardiomyopathy (Keshan disease)? Interestingly, an animal study found reduced activity of the free radical-quenching enzyme glutathione peroxidase, increased Coxsackie virus replication, more heart damage, and increased death rate in selenium deficient animals. Coxsackie viral infection damages the heart and the infection is much more active when selenium is lacking. Actually, when a benign form of the virus was injected into selenium deficient animals, the virus mutated into a destructive form. The same thing was found with a mild strain of influenza virus. Why does this matter?
Selenium is an essential trace mineral (your body can’t make it) with several important functions in the body. It is a coenzyme for the function of a free-radical neutralizing antioxidant enzyme, glutathione peroxidase, and is a component of other selenoproteins, as well. When selenium is lacking, there is more damage by free radicals. Mice lacking glutathione peroxidase have viruses that mutate into more damaging forms - likely from unopposed tissue-damaging free radicals. People with Keshan disease are more likely to have a genetic variant of glutathione peroxidase that makes it less efficient. This will necessitate a higher amount of selenium to compensate.
A large proportion of animals and humans in China are apparently selenium deficient. This allows for viruses to mutate and become more virulent. It allows for accelerated viral replication. This is likely why China is a breeding ground for pandemic viruses.
Viral infections cause oxidative stress, which in turn fosters more viral replication, resulting in a vicious cycle. Adequate selenium is required to neutralize these free radicals and break the cycle. Selenium has been referred to as birth control for viruses. Practice “safe sex” - eat some Brazil nuts - the best food source of selenium.
If you want to have your selenium levels measured, that can be done. I usually order a blood test for selenium status. However, I believe there is little downside to simply supplementing with 200-600 mcg daily of selenium to provide some protection against coronavirus infection. This is one such product: Selenium.
Selenium supplements were given to people in areas affected by Keshan disease, resulting in dramatic improvement. To summarize, Keshan disease appears to involve viral infection and selenium deficiency, magnified by genetics that require more selenium. Don’t let anyone tell you that diet and supplements are not absolutely powerful, essential modifiers of health status; outcomes of viral infections included. I saw a medical doctor on television the other day state that supplements are not needed. That’s disappointing but not surprising, given that the average medical school includes only about 10 hours of nutrition discussion. Selenium is not “the cure” for COVID-19. It is, however, one effective weapon that should not be overlooked in our battle against this virus. We need every advantage we can get. I will be discussing others soon.