Type 2 diabetes mellitus (T2DM) is strongly associated with cardiovascular mortality, with coronary artery disease (CAD) being the main manifestation. The pathophysiology of this condition is exacerbated by the accumulation of advanced glycation end-products (AGEs), specifically carboxymethyllysine (CML), which intensifies inflammation, vascular dysfunction, and the progression of atherosclerosis. Considering that diet is the primary exogenous source of these compounds and a modifiable risk factor, this study aimed to evaluate the effect of a low-CML diet on reducing serum levels in patients with T2DM and CAD. This was a randomized clinical trial involving 36 overweight elderly patients, divided into an intervention group (n=19, assigned to a low-CML diet) and a control group (n=17), over a period of 15 days. The intervention reduced CML intake by approximately 56% (p<0.001), resulting in a 30% decrease in serum CML (from 2.90 to 2.03 µg/g; p=0.015). The proposed diet also increased fiber intake and significantly reduced the consumption of trans fatty acids, polyunsaturated fatty acids, and cholesterol. A positive correlation was observed between serum CML and lipid peroxidation (r=0.33; p=0.045), body water (r=0.35; p=0.03), and dietary AGEs (r=0.52; p<0.01), indicating a relationship with oxidative stress and osmolarity. We conclude that reducing CML consumption for 15 days, through temperature control in food preparation, proved to be an effective nutritional strategy. The intervention promoted vascular and metabolic protection, suggesting potential for ameliorating diabetes complications. Future studies with a longer duration and the development of Brazilian food composition tables are recommended to expand upon these findings.