BACKGROUND: Carotid intima-media thickness (CIMT) is increasingly used as a prognostic indicator for early atherosclerosis and the development of cardiovascular disease. The objective of this study is to assess the exact effects of bariatric surgery on CIMT reduction in different age groups. METHODS: CIMT was measured just proximal to the bifurcation of the carotid artery in 166 patients with mean body mass index of 43.4 kg/m before and at 6 and 12 months after bariatric surgery. Preoperative CIMT and Framingham Risk Score (FRS) were compared to measurements at 6 and 12 months, postoperatively. Impact of age on CIMT change and cardiovascular risk reduction was analyzed. RESULTS: Median follow-up was 12 months; 12% were lost to follow-up. Mean CIMT values at 12 months after bariatric surgery were significantly lower compared to baseline (0.619 vs. 0.587 mm, p = 0.005 in women and 0.675 vs. 0.622 mm, p = 0.037 in men, respectively), and these effects were statistically significant in all age groups. The mean reduction of CIMT for patients < 50 years at 12 months was 0.043 mm (- 7.0%), while CIMT was reduced with 0.013 mm for patients ≥ 50 years (- 1.9%, p = 0.022). At 12 months after bariatric surgery, FRS had decreased with 52% in patients < 50 years as compared with 35% in patients ≥ 50 years (p = 0.025). CONCLUSIONS: Bariatric surgery resulted in a significant CIMT decrease in patients with morbid obesity in all evaluated age categories. These beneficial effects of bariatric surgery were more pronounced in younger patients, while cardiovascular risk reduction by bariatric surgery appeared inferior in patients of 50 years and older.