New research suggests that drinking more than 30 fluid ounces (about four cups) of coffee is linked to a reduced risk of multiple sclerosis (MS). The study, published in the Journal of Neurology, Neurosurgery & Psychiatry, adds its conclusions to the growing body of evidence indicating coffee’s beneficial health effects. Coffee is a central nervous system stimulant, and is capable of suppressing chemicals involved in the inflammatory response, which researchers say could explain the association.

The association was based on two representative population studies; one from Sweden involving 1,620 adults with MS and a control group of 2,788; and a United States study comprising 1,159 people with MS and 1,172 healthy people. Both studies asked participants about their coffee drinking habits — the Swedish study asked about average daily consumption across different time periods, and the U.S. study inquired about maximum daily consumption and age at which the participants began drinking coffee. Researchers took this information and estimated coffee consumption before and after MS onset in those with the condition and compared this to those in the healthy groups.

The results showed a consistently higher risk of MS among those drinking fewer cups of coffee every day in both studies, even after controlling for other potentially relevant factors like smoking and weight. The more coffee drunk, the findings showed, the lower the risk of MS. No firm conclusions can be drawn from the study, as it is observational, and the researchers caution inaccurate recall of coffee consumption cannot be ruled out when considering conclusions.

However, the findings do back up animal studies of multiple sclerosis, and point to caffeine as protective against neurodegenerative diseases such as Alzheimer’s and Parkinson’s. Further research is key for drawing firmer conclusions, the researchers said, since another chemical component of coffee could be responsible for the association. Drs. Elaine Kingwell and Jose Maria Andreas Wijnands, of the Faculty of Medicine, University of British Columbia, point out in an accompanying editorial that previous studies on the issue have come up with inconsistent results.

“Given the well-known challenges that exist in untangling the nature of associations between dietary factors and disease risk, these inconsistencies are perhaps not surprising,” they write. “Although it remains to be shown whether drinking coffee can prevent the development of MS, the results of these thorough analyses add to the growing evidence for the beneficial health effects of coffee.”

The editorial concludes that this study at least warrants further investigation into the potential role of coffee in MS prevention.

Source: Hedstrom A, Mowry E, Gianfrancesco M, Shao X, Schaefer C, Shen L, et al. High consumption of coffee is associated with decreased multiple sclerosis risk; results from two independent studies. Journal of Neurology Neurosurgery & Psychiatry. 2016.