Re‐Emergence of Thiamine Deficiency Among Pregnant and Lactating Women in Northeast India

Thiamine (vitamin B1) deficiency, once considered controlled in India, has re‐emerged in parts of Northeast India, raising concern for maternal and infant health. We conducted a community‐based cross‐sectional study during 2023–2024 to estimate its prevalence and dietary determinants among pregnant and lactating women in the Barak Valley of Assam and adjoining districts of Tripura. Using multistage cluster sampling, women were recruited from 120 villages with documented beriberi clusters. Thiamine status was assessed by determining the erythrocyte transketolase activation coefficient (ETKAC), a functional marker, and whole‐blood thiamine diphosphate (ThDP), a biochemical marker measured by high‐performance liquid chromatography. Of 1329 women, 1083 were analyzed. Both markers gave similar estimates of suboptimal status: 20.1% by ThDP (95% CI: 17.8−22.6; deficient: 4.9%, marginal: 15.2%) and 20.6% by ETKAC (95% CI: 18.3−23.1; severe: 8.5%, marginal: 12.1%), higher among pregnant than lactating women. Diets were rice‐based with low diversity. As the functional marker ETKAC was more sensitive to dietary context, we focused on its determinants: stored rice, washing rice repeatedly before cooking, and drinking salted tea were each associated with higher odds of ETKAC‐defined suboptimal status. Socioeconomic disadvantage further increased risk. This substantial, subclinical, preventable burden driven by dietary monotony and thiamine‐depleting rice practices underscores the need for targeted maternal nutrition strategies.