Ashwagandha

Ashwagandha is a plant in the nightshade family commonly used as a medicinal herb in Ayurvedic medicine.

Also known as: Withania Somnifera, Indian Ginseng, Poison Gooseberry, Winter Cherry 

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https://www.lifeextension.com/magazine/2012/6/new-reason-avoid-stress/page-01

https://www.lifeextension.com/magazine/2007/2/report_cognitex/page-03