Micronutrients & recovery
Selenium intake exhibits extreme variability based on soil geology and plant species, making it difficult to define a single optimal intake level without considering specific health contexts and selenium species.
Do not assume a standard selenium supplement dose is optimal for you. Your selenium needs depend heavily on where your food is grown (soil content), what type of selenium it is (e.g., selenomethionine vs. selenite), and your specific health conditions. If you live in a low-selenium region or have specific health risks, consult a professional to determine if you need more, less, or no supplementation, as both deficiency and toxicity are possible.
Though it is clear that there are adverse consequences for health of both deficient and excessive intake, health effects at intermediate levels of intake are less certain. Thus it is difficult to define optimal intake which depends on a large number of factors, such as which functions of Se are most relevant to a particular disease state, which species of Se is most prominent in the Se source... and whether the ability to make selenoproteins may be compromised.
Why this rating
The paper is a comprehensive review citing numerous observational studies, RCTs, and epidemiological data, though it highlights the complexity and lack of consensus on 'optimal' levels.
Source
Food-chain selenium and human health: emphasis on intake
Margaret P. Rayman · British Journal Of Nutrition · 2008
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