Among a group of older women, self-reported caffeine consumption of more than 261 mg per day was associated with a 36 percent reduction in the risk of incident dementia over 10 years of follow-up. This level is equivalent to two to three 8-oz cups of coffee per day, five to six 8-oz cups of black tea, or seven to eight 12-ounce cans of cola.
The high levels of caffeine in energy drinks may lead to cardiac complications. A new case report adds to previous reports of adverse cardiovascular events related to consuming energy drinks, including abnormal heart rhythms (arrhythmias).
New research shows that drinking one 16-ounce energy drink can increase blood pressure and stress hormone responses significantly. This raises the concern that these response changes could increase the risk of cardiovascular events.