Follicular lymphoma (FL), the second most common non-Hodgkin's lymphoma (NHL), is well characterised by a classic histological appearance and an indolent course. Current treatment protocols for FL range from close observation to immunotherapy, chemotherapy and/or radiotherapies. We report the case of a 42-year-old woman diagnosed by excisional biopsy with stage IIIa, grade 1 FL. In addition to close observation, the patient underwent a medically supervised, 21-day water-only fast after which enlarged lymph nodes were substantially reduced in size. The patient then consumed a diet of minimally processed plant foods free of added sugar, oil and salt (SOS), and has remained on the diet since leaving the residential facility. At 6 and 9-month follow-up visits, the patient's lymph nodes were non-palpable and she remained asymptomatic. This case establishes a basis for further studies evaluating water-only fasting and a plant foods, SOS-free diet as a treatment protocol for FL.