What is cranberry?

Cranberry (Vaccinium macrocarpon) is a tart, deep red berry native to North America. Indigenous communities have long valued it as both a food and traditional remedy.

Its distinctive sourness comes from naturally occurring organic acids and polyphenols. Cranberry is particularly rich in a type of proanthocyanidin called A type proanthocyanidins.

These compounds are thought to contribute to cranberry’s association with urinary tract health. Cranberry is one of the most extensively researched botanicals for this purpose, with clinical studies examining its potential benefits over several decades.

Urinary tract health

Cranberry’s main mechanism for urinary tract support is its effect on bacterial adhesion. It contains A type proanthocyanidins (PACs), a distinctive form of these plant compounds.

Research suggests these PACs can reduce the ability of certain bacteria, particularly E. coli, to attach to cells lining the urinary tract. This differs from a direct antimicrobial action that kills bacteria.

By reducing bacterial adhesion, cranberry may help support the body’s natural defences within the urinary tract. This mechanism has contributed to cranberry’s longstanding use for urinary tract health, particularly among women.

Antioxidant protection and oral health

Cranberry also provides anthocyanins and other polyphenols with antioxidant properties. These compounds contribute to the berry’s overall nutritional profile and may help protect cells from oxidative stress.

Cranberry’s anti adhesion properties have also attracted interest in oral health. Research has explored whether its proanthocyanidins may reduce the adhesion of certain bacteria to teeth and gums.

This potential effect has prompted research into cranberry extracts for oral health. However, more research is needed to establish their practical benefits.

Choosing an effective cranberry supplement

When choosing a cranberry supplement, consider the product’s proanthocyanidin (PAC) content. Look for products that state a standardised PAC amount rather than only listing the total cranberry extract.

Some products measure PAC content using the BL-DMAC method. A stated PAC level makes it easier to compare the amount provided by different products.

Unsweetened cranberry juice is another dietary option. However, juice generally provides a lower concentration of PACs than standardised extracts.

Many cranberry products are naturally tart, so commercial juices may contain added sugars or sweeteners. Check the nutrition information if you want to limit your sugar intake.

Cranberry is sometimes combined with D-mannose, a simple sugar with a different proposed mechanism. This combination is commonly used in products designed to support urinary tract health.