Effects of selenium toxicity and deficiency on humans

Thesis Abstract

Abstract
Selenium is an essential micronutrient that plays a crucial role in human health. Both deficiency and toxicity of selenium can have significant impacts on various physiological processes in the human body. Selenium deficiency is associated with an increased risk of various chronic diseases, such as cardiovascular disease, certain types of cancer, and impaired immune function. On the other hand, selenium toxicity can result in adverse health effects, including gastrointestinal disturbances, hair and nail brittleness, and neurological abnormalities. The effects of selenium deficiency on humans are well-documented. In regions where the soil is deficient in selenium, populations are at a higher risk of developing health problems related to selenium deficiency. Insufficient dietary intake of selenium can lead to decreased activity of selenoproteins, which are essential for antioxidant defense mechanisms and thyroid hormone metabolism. As a result, individuals with selenium deficiency may experience oxidative stress, compromised immune function, and thyroid disorders. Conversely, selenium toxicity is a concern in regions where selenium levels in the soil are high or due to overconsumption of selenium supplements. Chronic exposure to high levels of selenium can lead to selenosis, a condition characterized by symptoms such as garlic odor breath, hair loss, and gastrointestinal disturbances. Selenium toxicity can also impact the nervous system, causing symptoms such as tremors, muscle weakness, and in severe cases, paralysis. The mechanisms underlying the effects of selenium toxicity and deficiency on human health are complex and involve interactions with various biological pathways. Selenium acts as a double-edged sword, where both inadequate and excessive levels can disrupt the delicate balance required for optimal health. Understanding the factors that influence selenium status in individuals, such as dietary intake, genetic variations, and environmental exposure, is crucial for mitigating the risks associated with selenium imbalances. In conclusion, selenium is a micronutrient with a narrow therapeutic range, where both deficiency and toxicity can have detrimental effects on human health. Maintaining an optimal selenium status is essential for supporting overall health and well-being. Further research is needed to elucidate the precise mechanisms by which selenium influences human health and to develop strategies for preventing and managing selenium-related disorders.