Quantitative ethnobotany and evidence-based analysis of antidiabetic medicinal plants used in Biswanath district, Assam, India.

Type 2 diabetes is a growing public health concern in India, while plant-based remedies remain important in Assam. This study documented plants used for diabetes-related complaints in Biswanath district, quantified diabetes-specific salience and consensus, and integrated ethnobotanical indices with pharmacological evidence. From December 2022 to March 2024, semi-structured interviews with 440 informants were complemented by voucher-based taxonomic authentication. Relative Frequency of Citation (RFC) and Fidelity Level (FL) were diabetes-specific, whereas Use Value (UV) measured ethnomedicinal versatility across all ailments. Published species-level antidiabetic evidence was graded as no eligible evidence, in vitro only, or in vivo and/or human. We documented 63 species in 57 genera and 39 families. Among 83 plant-part use records, fruit (22.9%) and leaf (21.7%) were most frequent. Andrographis paniculata (RFC = 0.223), Kalanchoe pinnata (0.200), and Nyctanthes arbor-tristis (0.180) were most frequently cited for diabetes; Allium sativum had the highest overall UV across all ailments (2.359), and Syzygium cumini the highest diabetes-specific FL (92.59%). Evidence-salience mapping placed 16 species (25.4%) in the Overlap zone; none met Gap-zone criteria under the species-level framework. Hydrocotyle sibthorpioides and Alocasia odora had only in vitro evidence. The framework supports prioritisation but does not establish the efficacy or safety of locally used plant parts or preparations.