In India, undernutrition is a key driver of the tuberculosis (TB) epidemic. The high burden of severe and very severe undernutrition leads to higher death rates among those with TB. Despite documentation of weight and height, body mass index calculations to prioritise nutrition support for those with severe and very severe undernutrition are lacking in India’s National Tuberculosis Elimination Programme. This state-level operational research in Chhattisgarh led to a change in state-level policy in this regard. The learnings from this operational research–guided policy change have lessons for other states in India.