Study Recognizes Potential of Cranberry Polyphenols on Short-Term Memory and Cortisol

A randomized, double-blind, controlled trial published in Clinical Nutrition showed promise for the benefit of cranberry polyphenols on cortisol levels and cognitive function, according to the Cranberry Institute, which funded the study.

The clinical trial involved 72 college students aged 20-25 years old. Participants were given 8 fluid ounces of a cranberry drink daily at breakfast for 12 weeks.

When compared to placebo, those in the cranberry group had significant changes in circulating polyphenol metabolite concentrations. Although improvements in self-reported mood, stress, anxiety, and depression were not observed, it’s possible that this healthy, young population had limited potential for observable improvement in these areas.

Those consuming the cranberry drink showed reduced diurnal cortisol levels and enhancement of certain aspects of cognitive function, including short-term and phonological memory, or the brain’s ability to hold, remember, and process what is heard.

Cranberries are a significant source of bioactive compounds, including polyphenols such as anthocyanins, flavonoids, and proanthocyanidins (PACs). Anthocyanins are the flavonoids found in cranberries that give them their red color.

These compounds are quickly absorbed into the bloodstream and offer potent health benefits. Anthocyanins have anti-inflammatory effects and have been shown to cross the blood-brain barrier, which may contribute to supporting nerve cells in the brain.

Cranberries are also unique as they are a potent source of A-type PACs, which inhibit the adhesion of harmful bacteria in the body. They are well known for their ability to prevent urinary tract infections, but this anti-adhesion action also benefits the stomach and oral cavity, and research in this area continues to grow.

This study adds to research on the possible benefit of cranberries for memory. A 2022 RCT found that daily cranberry supplementation over a 12-week period in a group of 60 healthy older adults benefited neural functioning and episodic memory performance.