Background and objectives: Calorie restriction (CR) ameliorates preclinical models of multiple sclerosis (MS) through reduction of inflammation via multiple mechanisms including reduced adiposity and changes in pro-inflammatory adipokine levels. Daily and intermittent CR (iCR) have been tested in people with MS (pwMS) with benefits shown on fatigue and wellbeing measures. The aim of this trial was to study the effects of 12-week iCR on metabolic, immunological and clinical outcomes in pwMS. Methods: Participants with relapsing-remitting MS were randomly assigned to iCR or a control group for 12 weeks. Anthropometric measures, clinical and patient-reported outcomes, and blood samples were collected at baseline, 6 and 12 weeks. Oral glucose tolerance test and dual-energy X-ray absorptiometry were performed at baseline and week 12. Primary outcome of the study was change in leptin serum levels; secondary outcomes included changes in anthropometric and body composition measures, peripheral blood metabolic and immunologic profiling, and clinical measures. Mixed effects linear regression models were used to evaluate differences in the outcomes of interest between and within groups over time. Results: Forty-two pwMS were randomized, 34 completed the study (17 iCR and 17 control). Leptin levels decreased over the course of the study in the iCR group and were significantly lower in the iCR than the control group at 6 (mean difference 11.49 ug/dL, 95% CI 32.54, 9.54; P=0.01) and 12 weeks (6.97 ug/dL, 95% CI 28.02, 14.06; P=0.03). Adiponectin increased from baseline in the iCR, but not in the control cohort. We observed a significant reduction of weight, body mass index and body adiposity measures over the 6 and 12-weeks in participants randomized to iCR. Immune profiling showed a significant increase in CD45RO+ regulatory T cell numbers after 6 weeks of iCR. Lysophosphatidylcholine, lysophophatidylethanolamine and phosphatidylinositol lipids species were significantly increased after 12 weeks in the iCR group compared to baseline, and all three were higher at 12 weeks compared to controls. Exploratory cognitive testing demonstrated improvement in the symbol digit modality test score in the iCR group. Conclusions: Short term iCR is safe, feasible and can benefit metabolic and immunologic profiles in pwMS.