The journal Nutritional Neuroscience reported that the study involved 20 healthy young adults aged between 18 and 35, divided into two groups:

The first group received a dose of blackcurrant juice fortified with 500 milligrams of polyphenols, while the second group consumed a placebo drink similar in color and taste but without active compounds.

Researchers monitored changes in blood oxygen levels—which reflect cerebral blood flow activity—using near-infrared spectroscopy.

Results showed that just 35 minutes after consuming blackcurrant juice, oxyhemoglobin levels increased in the left frontal lobe of the first group, indicating improved blood flow and increased oxygen saturation in the brain. Conversely, deoxyhemoglobin levels decreased, suggesting enhanced efficiency of cerebral blood vessels and their ability to supply neurons with oxygen more effectively.

Dr. Anthony Watson, the study’s author and director of the Human Nutrition and Activity Research Centre at Newcastle University, commented on the findings:

“After consuming blackcurrant juice, we observed a significant increase in blood flow within the left frontal cortex, the area responsible for attention and decision-making. This corresponds with greater activity in the left side of the brain during working memory tasks.”

The researchers noted that blackcurrant berries are rich in polyphenolic compounds, especially anthocyanins, plant-based substances known for their positive effects on cardiovascular health.

Scientists suggest these compounds may boost nitric oxide production, which helps dilate blood vessels, or influence dopamine and serotonin levels in the brain—two neurotransmitters that play important roles in regulating blood flow and neurological functions related to focus and memory.