New scientific evidence shows that drinking plain old cranberry juice or eating cranberry sauce is better at fighting urinary tract infections than swallowing the berry’s extracts in condensed pill form or liquid.

Researchers at Worcester Polytechnic Institute arrived at that conclusion after they tested a group of compounds found in the berries that many scientists believed would be effective if put in pill form. But the berry and juice itself turned out to have better infection-fighting properties than the extract.

Writing in the journal Food Science and Biotechnology, the researchers admitted that they “are not yet clear” on just why nature’s own original cranberry is better for you than a lab-produced extract from the berry. But they said the cranberry juice and sauce worked better in their studies preventing bacterial growth that leads to infections.

“Cranberries have been recognized for their health benefits for a number of years, especially in the prevention of (urinary tract infections),” the researchers wrote. “While the mechanisms of action of cranberry products on bacterial adhesion and biofilm formation are not fully understood ... this study shows that cranberry juice is better at inhibiting" infection.