Cranberry

Studies in people

• Benefit

  Urinary tract infections³

  Cranberry products reduced urinary tract infections in women, children and people with catheters, though some groups saw no clear benefit.

• Benefit

  Urinary tract inflammation⁴

  Cranberry may help against urinary tract inflammation in adults and children, but more research is needed.

• Benefit

  Antioxidant levels after hard exercise⁵

  In rowers, cranberry extract raised resting and post-exercise antioxidant levels, but did not change inflammation or iron markers.

• Benefit

  Blood sugar control⁷

  In people with type 2 diabetes, cranberry juice daily for 12 weeks showed a helpful effect on blood sugar control.

• Concern

  Kidney stone risk⁸

  Cranberry tablets raised oxalate levels in healthy people's urine, which can help form kidney stones.

• Benefit

  Mood and memory in students⁹

  In students, cranberry drinks did not change mood, but memory improved and cortisol dropped.

• Benefit

  Urinary symptoms in women¹⁰

  In women with repeat cystitis, a cranberry, propolis and D-mannose sachet cleared urinary symptoms in most who took it.

• Benefit

  Gut bacteria balance¹¹

  In people, cranberry extract changed gut bacteria within four days, boosting Bifidobacterium and butyrate-producing bugs.

• Benefit

  Urinary tract infections in women¹²

  In women with repeat urinary infections, cranberry fruit powder led to fewer infections over six months.

• Benefit

  Blood pressure and cholesterol¹³

  In adults with extra weight, drinking cranberry juice daily slightly lowered daytime blood pressure and changed LDL particle size.

Animal and lab studies only

• Benefit

  Cancer cell growth¹⁶

  In lab studies, cranberry extracts and compounds slowed the growth of breast, colon, prostate and lung tumor cells.

• Benefit

  Gut inflammation in mice¹⁷

  In animal studies, eating cranberry eased gut inflammation and changed gut bacteria in mice.

Study type not stated

• Concern

  Blood thinners and kidney stones¹⁴

  Cranberry seems fine for most people, but large amounts may affect blood thinners or kidney stones.

• Benefit

  Urinary tract health¹⁵

  Cranberry juice may help keep urinary tract health, but how much cranberry proanthocyanidins the body absorbs is still not known.

Single cases of misuse or overdose

One person or one incident, such as an accidental overdose or a mistake in a kitchen or factory. They are real, but a single case does not show what happens at normal amounts, so the signal does not count them.

• Blood clotting with warfarin⁶

  A woman on warfarin saw her blood clotting test rise after drinking cranberry juice daily, twice.

The signal at the top counts the findings in people and in animal and lab studies. A concern in studies of people outranks animal and lab studies, and “No concerns” needs at least one finding in people. When most findings in people point one way, the page leans that way (“Mostly”), and every finding is still shown. Findings whose study type is not stated are shown but not counted. This page is a reference, not medical advice. It describes what regulators and published research say. Talk to a doctor or dietitian about your own diet.