Lifestyle Changes Following a Health Promotion Intervention in Adults Aged 40 to 60 Years with Type 2 Diabetes Mellitus in Rural Mexico: A Preliminary Pre–Post Single-Group Study

Type 2 diabetes mellitus (T2DM) is a global public health problem whose management largely depends on lifestyle modification. Objective: In this preliminary study, we examined short-term changes in the lifestyle of adults aged 40 to 60 years with T2DM at the Taxhuada Health Center, Hidalgo, Mexico, following a health promotion intervention. Method: A quantitative, pre-experimental, single-group study with pre- and post-intervention measurements was conducted without a control group (n = 25 adults with T2DM). A seven-session educational health promotion intervention, grounded in the Health Belief Model (MCS), was implemented between February and March 2024, and lifestyle was assessed using the Instrument to Measure Lifestyle in Diabetics (IMEVID; Cronbach’s α = 0.78 in this sample). Results: Prior to the intervention, 52.0% of participants had an “unhealthy” lifestyle (score ≤ 70); following the intervention, 88.0% were classified as “healthy” (score > 70). A statistically significant increase in the overall IMEVID score was observed following the intervention (Wilcoxon Z = −4.39, p < 0.001, r = 0.88, large effect), and a significant change in clinical classification (exact McNemar p = 0.002). All 25 participants improved their IMEVID total score. Significant score increases were observed in physical activity, alcohol consumption, disease knowledge, emotional aspects, and treatment adherence, but not in diet or tobacco consumption. Conclusions: These preliminary findings suggest that the seven-session health promotion intervention was associated with short-term improvements in self-reported lifestyle scores among participants with T2DM in a rural Mexican primary care setting. Given the small sample size (n = 25), the absence of a control group, and the reliance on self-report, these results should be interpreted with caution and confirmed in future controlled studies with larger samples.