Status, antioxidant riboflavin

Glutathione reductase has selenium at the catalytic site, as a selenocysteine residue (section 11.15.2.5) this explains the role of selenium as an antioxidant nutrient. Glutathione reductase is a flavoprotein, and is especially sensitive to riboflavin (vitamin B ) depletion as discussed in section 11.7.4.1, measurement of glutathione reductase is used as a means of assessing riboflavin status. 

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