berberine

Berberine is a naturally occurring yellow plant compound found in several botanicals, including European barberry, goldenseal, goldthread, Oregon grape, phellodendron, and tree turmeric. Plants that contain it have a long history of use in Ayurvedic medicine and traditional Chinese medicine, and it is sold today as a dietary supplement.

According to NCCIH, the evidence for berberine is preliminary and not conclusive. Some research suggests it may have a small effect on lowering blood glucose in people with type 2 diabetes and may help reduce cholesterol levels. For weight loss, NCCIH says there "isn't enough rigorous scientific evidence" to determine whether it works; a 2022 review reported decreases in weight and BMI, but many of the included studies had a high risk of bias and produced inconsistent results. NCCIH has reported a possible benefit for blood pressure only when berberine was combined with the prescription medication amlodipine, not on its own. The agency states that additional high-quality research is needed before firm conclusions can be drawn, so berberine should not be assumed to treat or cure any condition.

NCCIH does not set a recommended dose. In studies, effects on body weight were seen mainly at doses above 1 gram per day taken for more than 8 weeks. Because berberine can affect blood sugar, blood pressure, and the way some medications work, talk with a clinician before starting it, especially if you take prescription drugs or manage a chronic condition.

NCCIH notes that when taken orally berberine is generally well tolerated, but it is "not without its risks and side effects." People who are pregnant or breastfeeding should not use it, and it should not be given to infants, because it can cause or worsen jaundice in newborns and may lead to a life-threatening condition called kernicterus (a type of brain damage from a buildup of bilirubin).

Reported side effects are mostly gastrointestinal and can include nausea, vomiting, abdominal pain, bloating, constipation, and diarrhea.

NCCIH reports that berberine can interact with cyclosporine, a medication used to prevent rejection of transplanted organs, and warns more broadly that it may interact with other medicines in harmful ways. Because it may lower blood sugar and blood pressure, it could add to the effects of diabetes or blood-pressure medications. Discuss potential interactions with a healthcare provider or pharmacist before use.