Micronutrients & recovery
Adequate dietary selenium intake is essential for optimal immune function, particularly enhancing T-cell proliferation, NK cell activity, and antibody responses, with the strongest benefits observed when correcting selenium deficiency rather than supplementing already sufficient levels.
If you live in a region with low soil selenium (parts of China, Europe, NZ) or have dietary restrictions, getting enough selenium (55-75 mcg/day) is crucial for a robust immune system, especially as you age. However, if you already eat a varied diet with Brazil nuts, seafood, or meat, extra selenium supplements likely offer no additional immune benefit and may carry risks. Focus on food sources first.
Selenium supplementation, for the most part, is immuno-stimulatory... This depends on the baseline selenium status and the strongest effects can be seen when supplementation boosts selenium levels from inadequate to adequate while the benefits of increasing an adequate selenium level to supra-nutritional levels is less clear.
Why this rating
The paper is a comprehensive review citing numerous human observational studies, clinical trials, and mechanistic animal models, though it notes mixed results in some areas.
Source
Selenium, Selenoproteins, and Immunity
Joseph C. Avery et al. · Nutrients · 2018
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