Individualized medical nutrition therapy with weekly follow-up improves glycemic control, inflammation, and reduces circulating zonulin in adults with type 2 diabetes mellitus: a randomized controlled trial.

BACKGROUND: Medical nutrition therapy (MNT) is a key component of type 2 diabetes mellitus (T2DM) management, but evidence regarding its effects on inflammation and intestinal permeability-related markers remains limited. In this randomized controlled trial we evaluated the effects of individualized MNT with weekly follow-up on glycemic control, inflammatory markers, and zonulin in adults with T2DM. METHODS: Forty-six adults with T2DM receiving oral antidiabetic treatment were randomly assigned to an individualized MNT group or a control group for 12 wk. The intervention group received individualized dietary counseling with weekly follow-up, whereas the control group received standard dietary advice at baseline only. Outcomes included anthropometric measures, glycemic parameters, lipid profile, inflammatory markers, zonulin, dietary intake, and physical activity. RESULTS: Compared with the control group, the individualized MNT group showed greater reductions in fasting plasma glucose (Δ: -56.52 ± 33.9 mg/dL) and HbA1c (Δ: -1.54 ± 0.5%) over 12 wk (P < 0.001). Significant decreases were also observed in tumor necrosis factor-α (TNF-α), interleukin-6, and zonulin, together with improvements in body weight, BMI, self-care behaviors, and quality of life. Higher HbA1c was positively associated with TNF-α (β = 0.27, P = 0.009), and TNF-α was positively associated with zonulin (β = 0.53, P = 0.002). CONCLUSIONS: Individualized MNT with weekly follow-up was associated with improved glycemic control, lower inflammatory marker levels, and reduced circulating zonulin levels in adults with T2DM. These findings support the potential value of structured, individualized dietary management with regular follow-ups in T2DM care.