New Delhi, Oct 29 Prime Minister Narendra Modi on Sunday talked about the benefits of Chhath Puja, saying it helped to prevent diseases. "Sun prayer or Chhath Puja is a festival of environment protection, prevention of diseases and discipline. Importance of cleanliness in our lives is attached to this festival," Modi said in his monthly radio address 'Mann ki Baat'. He said the festival was connected with nature and its worship. "While the sun and water are the centre of the Festival, bamboo, clay pots and fruits are the items which are used while performing the Puja." Chhath, held on October 25 this year, is one of the most popular festivals in eastern Uttar Pradesh and Bihar.