Mayotte, a French overseas territory, experienced an outbreak of infantile beriberi in 2004, a condition caused by a deficiency in thiamine (vitamin B1). Preventive measures were subsequently implemented, but no recent assessment has been conducted on the evolution of these deficiencies in the territory. The objective of the study was to characterize the epidemiological situation of thiamine deficiency in Mayotte between 2008 and 2020. Cases of thiamine deficiency were identified using data from the Hospital Information Systems Medicalization Program (PMSI) of the Mayotte Hospital Center from January 1, 2008, to December 31, 2020. They were described by sex, age, and date of hospitalization. Between January 2008 and December 2020, 256 cases of thiamine deficiency were identified, of which 4 patients died. The median age of the cases was 28 years (95% CI: [22–39]). The male-to-female sex ratio was 0.4, and women of childbearing age (between 15 and 44 years) accounted for 61% of cases. Beriberi was observed in 22 children under 5 years of age, nearly all of whom (20/22) were under 1 year old. An increase in cases was observed starting in 2014, primarily affecting women: N=183/256, or 76% of cases identified after 2014, with a peak in 2019 (N=42). Starting in 2018, an increase in cases among children was also observed (10 cases recorded), whereas no cases had been identified between 2016 and 2017. The study’s results demonstrate the persistence of thiamine deficiency cases in Mayotte, primarily among women of childbearing age. The evolution of prevention efforts, their reinforcement, and the improvement of dietary diversity are essential levers for action in the fight against these deficiencies.