Toronto: Excessive intake of coffee is likely to reduce the risk of multiple sclerosis (MS), an autoimmune condition affecting the nerve cells, finds a study.

The findings, which add to the growing evidence of health benefits of coffee, showed that the higher the quantity of coffee consumed in a day, the lower is the risk of multiple sclerosis.

More than 900 ml (30 fluid ounces), or about six cups, a day can reduce the risk of MS.

The risk of MS is higher among those drinking fewer cups of coffee each day, even after taking account of potentially important influential factors, such as smoking during the teenage years, said Elaine Kingwell from the University of British Columbia in Canada.

The animal studies of MS have pointed out the evidence in favour of caffeine’s protective effects against the neurodegenerative diseases such as Alzheimer’s and Parkinson’s.

Caffeine, a central nervous system stimulant, has neuroprotective properties and can suppress the production of chemicals involved in the inflammatory response, describing its association with MS, the researchers explained.

The researchers, in the study published online in the Journal of Neurology Neurosurgery & Psychiatry, based their findings on two representative population studies.

The first study they referred to was conducted in Sweden comprising 1620 adults with MS and 2788 adults with no symptoms of it, the second one was a US study comprising 1159 people with MS and 1172 people without any symptoms of it.

In both the studies, the participants were quizzed about their maximum daily consumption of coffee.

The researchers then used this information to estimate coffee consumption during MS symptoms in those with the condition and compared with the healthy groups.

In the Swedish study, coffee consumption was associated with a 28-30 percent lower risk of MS among those drinking more than six cups (900 ml) every day.

Similar results were found in the US study, with a 26-31 percent lower risk among those drinking more than 948 ml daily at least five years beforehand and at the start of symptoms compared with those who never drank coffee.

Multiple sclerosis a serious illness affecting the nerve cells of the brain and spine that gradually makes it difficult for someone to move, speak, or see.