Long-term ingestion of excessive levels of selenium (> 1000 µg/day) may produce fatigue, depression, arthritis, hair or fingernail loss, garlicky breath or body odour and gastrointestinal disorders or irritability.
The organic form of selenium found in high-selenium yeast is often preferred because it is less toxic.
The National Health and Medical Research Council of Australia states that selenium intake should not exceed 600 µg/day.
Selenium may reduce associated nephrotoxicity, myeloid suppression and weight loss, according to in vitro and in vivo tests — beneficial interaction.
HEAVY METALS (E.G. MERCURY, LEAD, ARSENIC, SILVER AND CADMIUM)
Selenium reduces toxicity of heavy metals such as mercury, lead, arsenic, silver and cadmium by forming inert complexes — beneficial interaction.
Contraindications and Precautions
Sensitivity to selenium.
Considered safe in usual dietary doses; safety at higher levels is unknown.