A 12-week clinical study is recruiting people with relapsing-remitting multiple sclerosis (RRMS) to evaluate if intermittent fasting can improve their immune response, metabolism, and gut microbiome — the bacterial community that inhabits the gastrointestinal tract.
Its findings may also hint at whether such a diet might ease MS symptoms or alter discourse course and, if used in conjunction with other treatments, boost their efficacy.
Conducted by researchers at Washington University in St. Louis (WUSTL), Missouri, the trial is supported by their findings in an earlier mouse study.
Results showed that fasting worked to ease MS-like symptoms in a mouse model of the disease, the research team reported. Specifically, EAE mice fed every other day were less prone to symptoms that included difficulty in walking, limb weakness, and paralysis than mice allowed to eat freely.
This study, “Intermittent Fasting Confers Protection in CNS Autoimmunity by Altering the Gut Microbiota” was published in the journal Cell Metabolism in May.
A fasting diet also enriched bacterial diversity in the mice guts, and shifted immune cell populations there toward a lower inflammatory response. When gut bacteria were transferred from fasting mice to nonfasting mice, the later also were seen to be better protected against MS-like movement problems, supporting the influence of the gut microbiome on MS symptoms.
Several diets have been proposed to help ease disease progression in MS patients, but solid scientific evidence is lacking to support any one diet over another, leaving the issue much to an individual’s choice.
“The fact is that diet may indeed help with MS symptoms, but the studies haven’t been done,” Laura Piccio, MD, an associate professor of neurology at WUSTL and the study’s lead author, said in a WUSTL news release written by Tamara Bhandari.
Taking place at the Missouri university, the trial (NCT03539094) is expected to enroll 60 RRMS patients. Half will be randomly assigned to eat a standard Western-style diet seven days a week, and the other half to Western-style diet five days a week, with two days set aside for fasting (consuming a maximum of 500 calories each day).
On fasting days, patients can only drink water or calorie-free beverages and eat fresh, steamed or roasted non-starchy vegetables
All will undergo a neurological assessment, and provide blood and stool samples in the study’s beginning, at mid-point or week six, and at its end (week 12). Those using MS medications will continue on their prescribed treatment regimens throughout the study. More information, including enrollment information, is available here.
Piccio noted that a pilot study on diet in 16 MS patients showed that limiting calories every other day for two weeks led to immune and gut microbiome changes that resembled those observed in the mice study she helped to lead.
Its researchers concluded that intermittent fasting had the potential to positively manipulate the immune response in MS patients by changing their gut microbiome.
The gut microbiome plays a central role in digestion, and in producing vitamins and amino acids (the building blocks of proteins). But a growing body of evidence indicates that it also determines how our immune systems develops and matures. Indeed, an increasing number of studies link irregularities in the gut microbiome with MS.
“There are several possible ways fasting can affect inflammation and the immune response,” Piccio said. “One is by changing hormone levels. We found that levels of the anti-inflammatory hormone corticosterone were nearly twice as high in the fasting mice. But it also could act through the gut microbiome.”
The new trial will allow the team to analyze more deeply the effects of a fasting diet — and perhaps gather evidence for a larger study investigating if skipping meals can ease MS symptoms.
Its goal is to find out “whether people on limited fasts undergo changes to their metabolism, immune response and microbiome similar to what we see in the mouse,” Piccio said.
“I don’t think any physician working with this disease thinks you can cure MS with diet alone,” she added, “but we may be able to use it as an add-on to current treatments to help people feel better.”