Berberis vulgaris or barberry is a thorny shrub native to southern Europe and northwest Africa. Its tart berries are consumed as a healthy fruit, and have also long been used in traditional medicine.
Berberine is the main active ingredient in barberry, which has known antibacterial and antibiotic properties. Barberry extract is sometimes used to treat skin conditions and fungal conditions.
Taken internally, barberries are very rich in vitamin C, and have in the past been used to treat scurvy. Berberine helps to fight off infections and is thought to boost the immune system. It's also reported that berberine can ease inflammation and help to soothe intestinal pain.
Studies have shown that berberine is potent in the control of blood sugar, and it may also have beneficial biochemical actions on the heart. Because berberine aids in the secretion of bile, it may also help to lower cholesterol and to act as a detoxifying agent for the liver.
Barberry supplements are available in tablet, capsule or tincture form, and sometimes as a cream or a tea. Barberries can also be eaten dried, or juiced and mixed with other fruits to mitigate the bitter taste.