Evidence suggests low-grade inflammation as the cause of metabolic syndrome and suggests diet as a promoter of chronic inflammation. We evaluated the association between inflammatory diets and the development of metabolic syndrome in Mexican adults. A total of 399 participants of the Health Workers Cohort Study were included in this study. The follow-up period was 13 y. Metabolic syndrome definition was the presence of ≥3 of the following components: waist circumference ≥102 cm for males or ≥88 cm for females, blood pressure ≥130 mmHg for systolic or ≥85 mmHg for diastolic, HDL cholesterol <40 mg/dL for males and <50 mg/dL for females; triglycerides ≥150 mg/dL, and glucose ≥100 mg/dL. To evaluate the inflammatory potential of the diet we used the Dietary Inflammatory Index (DII), which was divided into quartiles. To assess the risk of metabolic syndrome we estimated HRs and 95% CIs using Cox proportional hazards models. After adjustment for potential confounders, we found a positive association between participants in the highest quartile (Q) of DII and the incidence of metabolic syndrome (HRQ4vsQ1= 1.99; 95% CI: 1.03, 3.85; P-trend = 0.04) over a period of 13 y. When we divided the metabolic syndrome by its components, we found that participants in the highest quartile of DII were associated with hypertriglyceridemia (HRQ4vsQ1= 2.28; 95% CI: 1.13, 4.57; P-trend = 0.01), hypertension (HRQ4vsQ1= 2.22; 95% CI: 1.03, 4.77; P-trend = 0.032), and abdominal obesity (HRQ4vsQ1= 2.68; 95% CI: 1.06, 6.79; P-trend = 0.02). A highly inflammatory diet is associated with metabolic syndrome, hypertension, abdominal obesity, and hypertriglyceridemia. Further studies are needed to corroborate the role of inflammation and diet in the development of metabolic syndrome; yet, a reduction in dietary components that have been linked to inflammation is desirable.