In two new case-control studies, conducted by a team from the Karolinska Institute in Stockholm, there was evidence that a high consumption of coffee, equivalent to more than six cups a day, is associated with a reduced risk of developing multiple sclerosis (MS ).
The authors point out that these results are in line with the already conducted observations with animal models on multiple sclerosis and the coffee and the caffeine were both also associated with a reduced risk for Parkinson’s disease.
Case-control studies have been conducted in Sweden and California. The Swedish study included 1620 adults with MS (case-patients) and a comparison group of 2,788 people matched for age and sex (controls); the Californian study included 1159 patients with multiple sclerosis (case-patients) and 1,172 healthy matched controls.
In both studies, participants were recommended to take coffee in different periods of time.
The results showed that the risk of MS was consistently higher among those whose coffee intake was minimal during each day in both studies, even after adjustment for confounding factors, such as smoking and weight during adolescence .
In the Swedish study, the intake of more than six cups of coffee a day was associated with a lower risk of 30% for MS.
In the Californian study those who drank more than 948 ml of coffee a day had a 31% lower risk of MS compared to those who never drank coffee.
The researchers suggest that possible mechanisms that may explain their results include observations from experimental studies that caffeine increases adenosine receptor 1A (which protects against experimental autoimmune encephalomyelitis, and reduces the production of pro-inflammatory cytokines) .
Certainly further studies are needed to determine whether it is actually caffeine, or if there is another molecule in the coffee at the base of the results and to evaluate the association between its consumption and the development of MS, and to assess mechanisms through which the coffee can act on new therapeutic targets. These interesting results suggest that the role of coffee in the MS protection clearly warrants further development surveys.
Furthermore this study is notable for its wide international particular sample of 2779 patients with multiple sclerosis and access to detailed information on several major potential confounders.
The authors were able to show that while smoking is a clear confounding factor and has an important mitigating effect, the association between the high consumption of coffee and the reduction of risk for MS was evident in people with and without a history of smoking.