Washington DC, May 13 -- A huge long-term study found that drinking two to three cups of coffee a day was linked to a much lower risk of dementia, especially before age 75.

Researchers say caffeine may help keep brain cells active while reducing inflammation and harmful plaque buildup associated with Alzheimer's disease. But more coffee wasn't better the protective effect appeared to level off after moderate intake.

Scientists say your daily coffee habit may do more than give you an energy boost. New research suggests that drinking a moderate amount of caffeinated coffee or tea could help lower the risk of dementia as people age.

However, the benefits appear to level off after a certain point, meaning more caffeine is not necessarily b...