HIF1A and anemia: The partial reversal of this effect at higher levels of nitrate was associated with increased renal Epo expression, possibly as a result of renal hypoxia due to the relative anemia brought about by nitrate’s effects on hepatic Epo. Indeed, acute anemia has been shown to stabilize renal HIF1 and HIF2 in mice, whilst renal EPO production increases exponentially on hemodilution (26).