The health effects of fasting have become an intriguing new subject of study. Besides the obvious benefit of weight loss for people who are overweight, multiple studies have come out suggesting intermittent fasting conveys numerous other health benefits like reduced blood pressure, normalized blood glucose levels and possibly, reduced risk of heart disease.
A new study published in Cell Reports
by researchers at the University of Southern California, Davis is now proposing that a fasting-like diet also reduces the symptoms of multiple sclerosis. This study included both mice and human subjects with multiple sclerosis.
It was found that the diet started a life-or-death process for cells that is apparently crucial for repairing the body. "During the fasting-mimicking diet, cortisone is produced and that initiates a killing of autoimmune cells," said the study's lead author, Valter Longo, a professor who heads the USC Longevity Institute at the Davis School of Gerontology. "This process also leads to the production of new healthy cells."
Multiple sclerosis (MS) is a neurological disease that affects an estimated 2.3 million people worldwide, according to the National MS Society. Symptoms of the disease are highly variable between individuals and range from blurred vision to paralysis.
Mice with an autoimmune disease, (experimental autoimmune encephalomyelitis, the most commonly used experimental model for multiple sclerosis), were put on a three cycle fasting-mimicking diet for three days every seven days, plus a control group on a normal diet for comparison. The results showed that diet mimicking fasting reduced disease symptoms in all of the mice and “caused complete recovery for 20 percent of the animals,” the researchers reported.
As a physiological readout, they observed increased levels of the hormone corticosterone, which controls metabolism. There was a reduction in the cytokines, which cause inflammation. Improvements in the white blood T cell counts were measured as well. Crucially, the researchers also found that the fasting-mimicking diet promoted a regeneration of the myelin sheath that was damaged by the autoimmunity.
Myelin is vital for the timely conduction of nerve impulses throughout the nervous system. In people with multiple sclerosis, T cells malfunction, attacking the myelin and damaging nerve fibers. Interrupting that degeneration while promoting regeneration is critical for delaying the disease's development. The periodic, regular fasts appear to trigger that regeneration.
"On the one hand, this fasting-mimicking diet kills bad immune cells," Longo said. "Then, after the mice return to the normal diet, the good immune cells but also the myelin-producing cells are generated, allowing a percentage of mice to reach a disease-free state."
The researchers were able to investigate the efficacy of the diet on people with multiple sclerosis through a pilot trial. Eighteen patients were put on the diet mimicking fasting for a seven day cycle followed by a Mediterranean diet for 6 months. In addition, for six months, 12 participants were on a normal diet, with 18 others were on a ketogenic diet. Those who got a fasting-mimicking, then Mediterranean diet cycle and those on a ketogenic diet reported improvements in their physical health, quality of life, and mental health.
"We are optimistic," Longo said. "What we don't want is patients trying to do this at home without involvement of their specialist or without understanding that larger trials are necessary to confirm that the diet, as a treatment, is effective against multiple sclerosis or other autoimmunities."
, Cell Reports