Does a bowl of blueberries a day keep dementia away?
The prevalence of cognitive impairment in general, and dementia in particular, is increasing with the expansion of the older adult population in the U.S. and other countries. Because we do not have effective curative medications and treatments, preventive approaches are critical to public health initiatives aimed at mitigating cognitive health problems. At our research center, we receive numerous questions about non-pharmacological strategies for preventing dementia and improving cognition. People are especially curious about cognitive enhancement exercises, physical exercise, and health comorbidities. Lately, however, we have recognized an increase in diet-related questions. One in particular involves the role of blueberries and blueberry supplements in dementia prevention. In other words, does a bowl of blueberries a day keep dementia away?
The answer is complicated. Blueberries contain polyphenolic compounds, which have positive antioxidant and anti-inflammatory effects. Anthocyanin, one of the polyphenolic compounds found in blueberries, has been shown to have lipid-lowering effects and is thought to improve metabolic function. In addition to blueberries, anthocyanins can be found in foods like strawberries, blackberries, cherries, eggplant, plums, raisins, red or purple grapes, red beans, red beets, red apples, red onions, and red cabbage. Maintaining a diet rich in fruits and vegetables is associated with a lowered risk of neurodegenerative disorders. Moreover, there have been some studies reporting improvement in cognitive performance in older adults who consume regular amounts of fruits and vegetables, inclusive of blueberries. Other studies have found that, following blueberry consumption, anthocyanins have been identified in the hippocampus and specific cortical areas.
While this is encouraging news, a few words of caution are in order to put blueberry consumption in context. Based on the available research literature, one can say that consumption of blueberries and other fruits and vegetables can contribute to positive physical, mental, and cognitive health. However, consumption of anthocyanin-rich foods like blueberries, is likely more effective as a preventative strategy than as actual treatment for memory impairment. Even as a preventative measure, it is unclear how many blueberries one needs to eat in order to realize a positive effect. The best approach for mitigating the risk of dementia is a combination of positive overall health, physical exercise, cognitive stimulation (such as the BCAT Working Memory Exercise Book), and proper diet. As for the latter, one should not only eat healthy foods routinely, but also subtract less healthy ones.