When Harshada Prakash Temghare was in her early 30s, her face began to swell until, she said, it looked “like a football”. Tests found nothing for nearly four months. Then a chest X-ray showed a lump larger than an apple on her right side. It was lymphoma, a cancer of the lymphatic system.

During her treatment, doctors proposed a package of chemotherapy and radiation that the family estimated would have cost Rs 20 to 22 lakh. Her husband, Prakash Temghare, said one question haunted them. “Nobody in our house has any addiction. How did cancer happen at 32 or 33?”

Oncologists gave no definite cause, but the family said they pointed to changing diets and lifestyles as a possible factor. The couple decided to overhaul what they ate. They turned to Abhinav Farmers Club, a collective of organic farmers, and to Dnyaneshwar Bodke, whom they call their guru.…