Ashwagandha

About Ashwagandha

Ashwagandha, Withania somnifera, is an evergreen shrub of the nightshade family native to India, the Middle East and parts of Africa. Its Sanskrit name refers to the smell of a horse, describing the odor of the root, and the species name somnifera means sleep inducing in Latin. In Ayurvedic medicine it is classified as a rasayana, or rejuvenating tonic, and it is often described as an adaptogen. The root contains steroidal lactones called withanolides, including withaferin A. Clinical trials, mostly small and of short duration, have examined root extracts for stress, anxiety, sleep, exercise performance and male fertility, and several report reductions in perceived stress and cortisol, but study quality varies and longer independent trials are limited. Reported side effects are usually mild, such as digestive upset and drowsiness, although rare cases of liver injury have been described. Ashwagandha may raise thyroid hormone levels and has effects on the immune system, its safety in pregnancy has not been established, and some countries have restricted its sale.