Cranberry (Vaccinium macrocarpon)

Table of Contents

Other names

Cranberry Fruit
Cranberry Juice Powder
Cranberry Extract (PAC-standardized)

Synopsis

Cranberry (Vaccinium macrocarpon) is a small, tart red berry native to North America, most famously used for its role in supporting urinary tract health. Rich in vitamin C, anthocyanins, flavonols, and unique polyphenols called proanthocyanidins (PACs), cranberries are both a nutrient-dense fruit and a powerful medicinal agent, particularly in preventing urinary tract infections (UTIs).

The primary mechanism behind cranberry’s medicinal benefit is its ability to inhibit bacterial adhesion, especially of Escherichia coli (E. coli), to the walls of the bladder and urinary tract. The A-type proanthocyanidins (distinct from those in other fruits like grapes) disrupt the fimbriae of E. coli, reducing their ability to colonize and cause infection. As such, cranberry is frequently used prophylactically, especially in individuals prone to recurrent UTIs.

In addition to urinary health, cranberry offers:

  • Antioxidant support, protecting cells from oxidative stress
  • Anti-inflammatory properties, particularly in mucosal linings
  • Oral and gastrointestinal health benefits, by inhibiting bacterial biofilms
  • Cardiovascular support, through mild cholesterol and blood pressure modulation

Cranberry is consumed as juice (preferably unsweetened), capsules, tablets, or whole-fruit extract powders, with standardized supplements offering more reliable dosing of active PACs than juice alone. It is generally safe for long-term use, although high-dose cranberry supplements may interact with blood thinners like warfarin due to mild antiplatelet effects.

Historical Use
Cranberries have been used for centuries by Native American tribes, who harvested them both as food and medicine. Known for their cooling, cleansing, and preserving qualities, cranberries were used to treat bladder and kidney conditions, wounds, fevers, and digestive upset. The berries were also mashed and mixed with dried meat and fat to make pemmican, a high-energy food used for travel and survival.

In early European-American herbalism, cranberries were adopted quickly into folk medicine and were used for scurvy prevention, thanks to their vitamin C content. Physicians in the 19th and early 20th centuries used cranberry to acidify urine and treat infections, a practice that anticipated modern findings on bacterial adhesion.

In modern herbal and functional medicine, cranberry is a staple remedy for:

  • Preventing UTIs, especially in women
  • Postmenopausal urinary health
  • Supporting bladder and kidney function
  • Maintaining oral and gut microbial balance

Though not typically used to treat active infections on its own, cranberry is often combined with D-mannose, uva ursi, goldenrod, or marshmallow root in bladder and kidney formulas. Its long history and growing body of clinical support continue to reinforce its reputation as one of the most effective natural agents for urinary tract protection.

Uses: Health Conditions

Bladder Infection (Traditional)
Blood in Urine (Traditional)
Kidney Infection (Traditional)
Pets (supplements for) (Traditional)

Body Systems

Urinary System (Traditional)
Circulatory System (Traditional)
Immune System (Traditional)
Kidneys (Traditional)