A recent study shows the effectiveness of cranberry against bacteria, spending money that seems to prove what we’ve been saying for a long time. The study tested a combination of cranberry and antibiotics against a very resistance bacterial line. In both cell culture and a preliminary animal model, bacteria proved more sensitive to cranberry-antibiotic combos than to antibiotics alone. The combos, which in every case incorporated proanthocyanidin (cPACs) derived from cranberries, appear to suppress two antibiotic resistance mechanisms.

Studies conducted at McGill University where scientists followed up on the popular notion that cranberry juice can help fight urinary tract infections. The scientists, led by chemical engineering professor Nathalie Tufenkji, decided to investigate cranberry molecules—specifically, cPACs—and how they might affect pathogenic bacteria. Ultimately, cPACs and antibiotics were jointly administered to bacteria responsible for urinary tract infections, pneumonia, and gastro-enteritis.

“Normally when we treat bacteria with an antibiotic in the lab, the bacteria eventually acquire resistance over time,” said Tufenkji, the study’s corresponding author. “But when we simultaneously treated the bacteria with an antibiotic and the cranberry extract, no resistance developed. We were very surprised by this, and we see it as an important opportunity.”

“These are really exciting results,” added coauthor Éric Déziel, a professor of microbiology at INRS (Institut national de la recherche scientifique) in Montreal. “The activity is generated by molecules called proanthocyanidins. There are several different kinds of proanthocyanidins, and they may work together to deliver this outcome. We’ll need to do more research to determine which ones are most active in synergy with the antibiotic.”