Mechanism of the Huangguoshu waterfall forest environment's promotive effect on human health in Guizhou, China.

The charm of the Huangguoshu waterfall scenery could be perceived by the participants and have a positive modulating effect on mood and cognitive function. In addition, the unique mixture of negative oxygen ions in this environment can increase the content of endogenous antioxidants and balance the metabolism of choline and amino acids.