To identify dietary total antioxidant capacity (DTAC) in people with MS (PwMS) and evaluate its interrelation with nutritional status and disease progression. Cross-sectional, quantitative study with 127 patients with MS recruited from the Interdisciplinary Center for Assistance, Research and Teaching in Neuroimmunology (CIAPEN) (Fortaleza, Ceará, Brazil). The clinical parameters were clinical phenotype, the expanded disability status scale (EDSS), the medical research council (MRC) muscle scale, and Magnetic Resonance Imaging (MRI) evaluation. Weight and height measurements were obtained to calculate the body mass index (BMI), waist circumference (WC) and estimate body fat percentage (BF%). The DTAC was estimated using food intake data from the 24DR and the intake of antioxidant supplements. As for the nutritional status, it was found that 48 (37.80%) and 64 (50.39%) had excess adiposity according to the BMI and BF%, respectively, and 67 (53.60%) had elevated WC. Higher DTAC was associated with higher WC (r = 0.192, p = 0.032) and BF% (r = 0.246, p = 0.005); and higher intake of energy (r = 0.418, p < 0.001). There was no association between the clinical phenotype of the disease, the EDSS, the presence of visible lesions and the DTAC tertiles. However, in the unadjusted model, it was observed that the second tertile of DTAC reduced by 64% (OR = 0.36; 95% CI: 0.14-0.96) the individual's chance of having lower muscle strength, assessed by the MRC muscle scale. Healthy nutrition, especially sufficient intake of dietary antioxidants, should be encouraged in PwMS.