Isha was born on 29 September, 1984 in Gujarat, India to an Australian musician father & a Gujarati artist mother. She lived in Ahmedabad, from where she moved to Delhi, Orissa, Vrindavan and Bangalore, before settling down in Trivandrum.
Isha's parents founded an arts school called Academy for Art Research, Training and Innovation (AARTI) in Trivandrum, Kerala where she lived for 13–14 years. At the age of thirteen, she began formal learning in dance from her mother Daksha Sheth at her dance school and learned Kalaripayattu, Kathak and Chhau dance as well as giving performances in twenty-two countries over last seven years.
According to an interview with India Daily, Isha stated she "lived a different life poles apart from the film industry. For 11 years I have been training eight to 10 hours a day in a very disciplined atmosphere where there is no distinction between boys and girls. I was not supposed to cry over a clipped nail. Beyond stage even my wardrobe has mostly unisexual dresses, jeans and T-shirts". She is a trained Malkam dancer, a part of folk dance.
Isha never gave acting in films much priority, until she was spotted by filmmaker Subhash Ghai who required someone with dancing skills to perform in his movie Kisna (2005). He offered her a main role in the film opposite Vivek Oberoi. The film did not do well but her dance performances were appreciated. She was also the dancer opposite Hritik Roshan in the Parle Hide & Seek commercial, performing a much appreciated dance duet with Hrithik Roshan.
Since then she has continued her dance performances on stage, as well as signing for several movies which were released in 2006 and 2007. She appeared as a female lead in the Hindi comedy Darwaza Bandh Rakho in 2006.