Magnesium oxide side effects
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Common Side Effects of Magnesium Oxide: Gastrointestinal and Systemic Reactions
Magnesium oxide is widely used as a supplement and laxative, but it can cause several side effects. The most common side effects are related to the digestive system, such as increased intestinal motility and sensations of gastric heaviness, especially at higher doses or with certain formulations. Microencapsulated forms of magnesium oxide have been shown to reduce these gastrointestinal side effects compared to standard magnesium oxide supplements .
Risk of Hypermagnesemia: Vulnerable Populations
A significant risk associated with magnesium oxide use is hypermagnesemia, a condition where blood magnesium levels become dangerously high. This risk is especially pronounced in elderly individuals with poor kidney function, low body weight, or a history of hyperuricemia, as well as in children, particularly those who are younger or leaner. These groups are more likely to develop side effects, including elevated magnesium levels in the blood, which can lead to serious complications 36. In rare cases, hypermagnesemia can cause symptoms such as loss of consciousness and circulatory collapse, especially when magnesium oxide is used alongside medications that slow bowel movements, like antipsychotics .
Biochemical and Genotoxic Effects: Laboratory and Animal Studies
Animal studies have shown that magnesium oxide, especially in nanoparticle form, can cause DNA damage, changes in chromosome structure, and alterations in liver enzyme levels. These effects are dose-dependent and can occur regardless of gender. Magnesium oxide nanoparticles can also interfere with proteins and enzymes, disrupt the redox balance in cells, and accumulate in various tissues 125. High doses have been linked to increased white and red blood cell counts, elevated liver enzymes, and histopathological changes in the liver, such as bile duct proliferation and congestion .
Reproductive and Long-Term Toxicity: Emerging Concerns
Research in rats indicates that high doses of magnesium oxide nanoparticles can negatively affect reproductive organs, causing changes in sex hormone levels and tissue structure in both males and females. These effects are more pronounced at higher doses and include both functional and structural damage to the testis and ovary . Long-term exposure to magnesium oxide nanoparticles may also pose risks such as allergenicity, mutagenicity, and embryotoxicity, highlighting the need for further toxicological studies .
Conclusion
Magnesium oxide is generally safe when used appropriately, but it can cause gastrointestinal discomfort, and in certain populations, there is a risk of serious side effects like hypermagnesemia. Animal studies suggest potential for DNA damage, liver changes, and reproductive toxicity at high doses, especially with nanoparticle forms. Special caution is needed for children, the elderly, and those with kidney problems. Newer formulations, such as microencapsulated magnesium oxide, may help reduce some side effects.
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