Are Blueberries A Brain Food?

Botanists estimate that blueberries have been around for over 13,000 years. These deep purple berries can be enjoyed, fresh and frozen, throughout the year in smoothies, jams, baked goods, or raw. Plump, juicy blueberries are not only a delicious fruit to enjoy at meals and snacks, but may also provide nutrients that help improve memory and learning ability, and decrease effects of degenerative diseases of the brain and nervous system.

Nutrients

Blueberries provide vitamin C, fiber, manganese, potassium, lutein, virtually no fat, and only 84 calories per cup. The deep purple color of the berries comes from anthocyanins, a subclass of flavonoids. Scientists are interested in dietary flavonoids because of their possible health benefits: they possess antioxidant, anti-inflammatory, and metal-chelating properties and modulate cell-signaling pathways.

Oxidative Stress

Oxidative stress is a major cause of disease in humans, including neurodegenerative diseases like Alzheimer's and Parkinson's diseases. Oxidative damage can be caused to cells, tissues and organs by the by-products of normal metabolic reactions, as well as exposure to environmental pollutants like cigarette smoke and excess alcohol consumption. Research has shown that antioxidants, including those found in blueberries, help decrease oxidative damage.

Cognitive Performance

A study in Greece, published in 2009, found wild blueberry extract increased cognitive performance in adult male mice. Mice that were given the extract showed a significant improvement in learning and memory compared to those not receiving the extract. The mice that received the extract also showed decreased signs of oxidative damage, as well as increased brain antioxidant levels. The research scientists concluded these findings "stress the critical impact of wild blueberry bioactive components on brain function."

Neurodegenerative Diseases

A prospective study in Dutch men found that smokers decreased risk of Alzheimer's disease by 50 percent for every 12 mg increase in total dietary flavonoid intake. A study of French men and women found that risk of dementia increased with lower levels of flavonoid intake. These studies took into account all dietary intake of flavonoids, not just those from blueberries.

Considerations

Much of the research regarding the benefits of blueberries and brain health has been done with animals, particularly in rats. The primary question is whether these benefits exist for humans as well? It is not clear whether the flavonoids in blueberries and their metabolites are available in the human brain. To date, research has not found a consistent inverse association with blueberry consumption and the risk of dementia or other neurodegenerative diseases in humans. While a definitive benefit for brain health has not been determined, there is no question regarding the overall health benefits of a diet high in fruit and vegetable intake.