Summary Background & aims The Dietary Inflammatory Index (DII) consists of a tool that assesses dietary inflammatory potential based on the assignment of an inflammatory score to a variety of nutrients, seasonings and bioactive compounds. Pro-inflammatory diets are associated to weight and abdominal fat excess. High Body Mass Index (BMI) and Waist Circumference (WC) seem to contribute to a worse prognosis in Multiple Sclerosis (MS) patients. Therefore, this study seeks to investigate the relation between anthropometric indexes and body adiposity with the clinical condition and the Dietary Inflammatory Index of MS individuals. Methods This is a cross-sectional, analytical study that included 137 MS patients residing in the Brazilian northeast. Through a structured questionnaire and medical records consultation, we collected data on demographics, nutritional state, arterial pressure, clinical and dietary variables. Clinical variables included the MS type, number of pulse therapies and attack rate in the last two years, number of days of most recent pulse therapy and muscular strength assessment scores (MRC) and most recent disability level (EDSS). The nutritional state was evaluated based on BMI, WC, waist-hip ratio (WHR), Body Roundness Index (BRI), Body Shape z score Index (ABSIz) and body fat percentage (%BF). The DII was calculated according to a validated methodology. Results The ABSIz presented a positive correlation with regards to the EDSS score (r = 0.294. p = 0.001). WC and WHR presented a negative correlation in relation to the number of pulse therapy days (r = −0.255. p = 0.022 and r = −0.251. p = 0.024). BMI and %BF were not correlated to clinical variables (p > 0.05). The DII was positively correlated to the BMI in people with progressive MS (r = 0.556. p = 0.025). Conclusions The DII may interfere in the nutritional state of MS patients and the nutritional state may affect disability levels but it is necessary to establish which nutritional indicator can better predict the relation between DII and the clinical condition of MS patients.