The Evaluation of Dietary Antioxidant Capacity, Dietary Inflammatory Index and Serum Biomarkers in Breast Cancer: A Prospective Study.

Dietary antioxidant capacity (dTAC) and dietary inflammatory index (DII) are commonly used to assess nutrition. This prospective study examined dTAC, DII, and serum biomarkers in women with breast cancer (BC). Patients were followed-up before surgery (T1), before chemotherapy (T2), at 6th (T3) and 12th months of chemotherapy (T4). Serum tumor necrosis factor alpha, interleukin 1ß, interleukin 6, protein carbonyl, malondialdehyde, total antioxidant capacity (TAC), and total oxidant status levels were analyzed. Dietary antioxidant intake, dTAC, and DII were determined using a three-day dietary record. dTAC was calculated using vitamin C equivalent (VCE), oxygen radical absorption capacity (ORAC), trolox equivalent antioxidant capacity (TEAC), total radical-trapping antioxidant parameter (TRAP), and ferrous ion reducing antioxidant potential (FRAP). This study included 32 women with BC and 32 controls (CG). ORAC, TEAC, TRAP, and FRAP were significantly lower in BC than in CG. During follow-up, only ORAC increased significantly at T2 compared to T1. A weak positive correlation was found between dTAC (VCE) and serum TAC levels at T2 (rho = 0.371, p = 0.036). The relationship between diet and serum biomarkers was not significant. Multicenter prospective studies on different age groups are needed to understand the association between diet and serum biomarkers levels in patients with BC.