Do all cranberry supplements contain enough proanthocyanidins?
All cranberries contain proanthocyanidins, but the amount varies dramatically between products. Therefore, it is important to choose a product that has been independently tested and certified for proanthocyanidin content (such as by NSF® International). If the actual content of proanthocyanidins in a cranberry supplement has not been measured and independently certified, the efficacy of that product is uncertain.
