Ashwagandha is a popular herb in Ayurvedic medicine, where it's been used for thousands of years to improve brain function. The herbal supplement and tea are derived from the ashwagandha plant, known by the botanical name Withania somnifera.It also promotes overall immunity, strength, energy and endurance." Adding to this, Consultant Nutritionist Rupali Datta said, "It is used to fight depression, anxiety, boost fertility and brain functioning. In addition, ashwagandha is known for its antibacterial, anti-inflammatory and anti-carcinogenic activities.