Multiple sclerosis (MS) is an inflammatory and immune-mediated neurological disease with multifactorial etiology. The specific etiopathogenetic mechanisms of MS are still unknown but it is clear that it results from a combination of genetic and environmental factors. Several studies have reported the possible role of diet as a risk factor for MS and its progression. To date, many dietary patterns and their association with MS have been studied, but data is still limited and inconclusive. Mediterranean Diet (MedDiet) has been associated with a lower risk of developing MS, compared to a Western-style diet. In one of investigators' studies, higher MedDiet adherence was associated with a 6-fold greater likelihood of having lower disease severity than those with low adherence. A significant restriction of carbohydrates (up to ketogenesis) can have beneficial effects on various parameters (inflammatory markers, oxidative stress, altered glucose metabolism) which are altered in subjects with MS. Ketogenic diet therapies (KDTs) have been recommended mainly for children with drug-resistant epilepsy, but in recent years they have been applied to Multiple Sclerosis. Preclinical studies in animal models evaluating the efficacy of KDTs in experimental autoimmune encephalomyelitis (EAE) found a beneficial effect of diet in slowing of disease progression, improvement of motor disability, reduction of inflammatory cytokines and reactive oxygen species. In a randomized study, improvements in health-related quality of life (HRQL) scores and a slight decrease in EDSS scores were found. An open-label, single-arm study of 20 patients with RRMS also reported that, after 6 months of MAD, no subjects had new or enlarging FLAIR/T2 lesions, with a significant improvement in the EDSS score, the Modified Fatigue Impact Scale subscales and arm. A 3-arm parallel-arm randomized controlled pilot study was planned to determine the effectiveness of a modified Atkins diet (MAD) compared to a Mediterranean diet (MedDiet) on quality of life in a population with MS.