Barberry 90ml Twin Pack

Barberry is usually a considered choice. These are the questions our naturopaths ask in store, mostly about which part of the plant you want and whether anything you already take gets in the way.

A good fit if

• You want to help keep your cholesterol and blood fats in the healthy range, which is where most barberry research has been done
• You're happy to eat the dried berries as a food every day, at about the amount the trials used
• You want a traditional bitter before meals, and you're comfortable that it rests on tradition rather than trials
• You'd rather start with a food you can cook with than a capsule

Check with us first if

• You take medicine for blood glucose. Barberry changed fasting glucose and insulin in pooled trials, so your prescriber needs to know and you may need to monitor your levels.
• You take a medicine where small changes in dose matter, such as cyclosporine or digoxin. At high doses, herbs containing berberine are expected to raise levels of medicines cleared by the CYP3A enzyme or carried by P-glycoprotein.
• You take metformin. Goldenseal, a related herb containing berberine, cut metformin levels by about a quarter, though berberine alone didn't do the same in animals.
• You have a sensitive gut. Mild, short-lived gut upset is the most commonly reported side effect, and it's more likely above about 0.5 g of berberine a day.
• You take any prescription medicine. Check with your doctor, pharmacist or our naturopaths before starting.

• Dried berries (zereshk). Best known for: The food form, sour and rich in anthocyanins, and the one the cholesterol and blood vessel trials actually used. Absorption: Not measured. No study we hold looked at how the whole fruit is absorbed. Typical use: Cooked into rice and stews, or eaten daily at the 10 g the trials used, about two heaped teaspoons.
• Fruit extract capsules. Best known for: A concentrated fruit preparation. One trial used 2,000 mg a day of a water-and-alcohol extract, and two others used capsules of unstated strength. Absorption: Not measured. Typical use: Label strengths vary, and none of the trials lets you convert its dose into a retail capsule.
• Root or bark liquid extract. Best known for: The Western herbal medicine form, and where the alkaloids are: berberine, berbamine, jateorrhizine, palmatine and oxycanthine. Absorption: Not measured. Typical use: Traditionally used as a bitter and digestive tonic, and to promote bile flow. That's tradition only, with no trial behind it.
• Dried root or stem bark, as a decoction. Best known for: The traditional home preparation, simmered in water. Absorption: Not measured. Typical use: One teaspoon of dried material simmered in a cup of water for 15 to 20 minutes, taken three times a day.
• Isolated berberine. Best known for: A different product: one purified alkaloid, with its own larger but lower-quality evidence. Absorption: Poor. A 500 mg dose reached a peak of only 0.4 ng/mL in the blood. Typical use: See our berberine page. Barberry can't borrow berberine's evidence, and berberine can't borrow barberry's.

Reference values. There isn't one. Barberry is a herb, not a nutrient, so the NHMRC doesn't set a recommended intake for it.

Typical supplemental range. Traditional herbal doses from the Southern Cross University monograph are 1 to 2 mL of a 1:5 tincture three times a day, 3 to 6 mL a day of a 1:2 liquid extract, or 1.5 to 3 g a day of dried root or stem bark. Those are bark doses, and no trial has tested them. The research used something else: 10 g a day of dried berries for 8 weeks, or 2,000 mg a day of a fruit extract in one trial. So there's no single studied dose for a barberry product. There's the traditional dose, in millilitres of bark extract, and the research dose, in grams of berries.

Upper level. Australia's permitted ingredients list (Schedule 1) sets no daily cap for Berberis vulgaris. That isn't permission to take a lot. The Southern Cross University monograph notes that more than 0.5 g of berberine a day may cause gut irritation and other side effects, and we don't know how much berberine is in a gram of barberry berry or bark. There's no dose for children, because it isn't for children under 12.

Worth knowing. Bitters are traditionally taken shortly before food. If you're eating the berries, they're a food, so treat them like one and cook with them. What you need depends on your age, diet and health, so talk to one of our naturopaths.

Food first, where the diet allows it.

• Dried barberries (zereshk), sold in Persian and Middle Eastern grocers: 10 g a day, roughly two heaped teaspoons, was the amount used in the cholesterol and blood vessel trials
• Fresh barberries: scarlet and about 1 cm long; used less often than the dried fruit, and no per-serve composition figure is available

If any of these sound like you, talk to one of our naturopaths or your doctor before you start.

• You're pregnant. It's not recommended (Southern Cross University monograph).
• You're breastfeeding. It's classed as unsafe (Herbal Reality), and Berberis aristata products must carry a pregnancy and breastfeeding warning.
• Children under 12, and newborns or young children with jaundice. Don't use it.
• You take glucose-lowering medicine. An added effect on glucose is plausible, so involve your prescriber.
• You take a medicine with a narrow safe dose range that's handled by CYP3A4 or P-glycoprotein, such as cyclosporine or digoxin. An interaction is predicted at high berberine doses.
• You take metformin. Goldenseal extract reduced metformin levels by about 23 to 27 per cent, although berberine alone didn't in mice.
• At commonly recommended doses, herbs containing berberine only weakly block the CYP3A4 and CYP2D6 enzymes.
• Mild stomach and bowel upsets are the common side effect, and more than 0.5 g of berberine a day may irritate the gut.
• There's no Schedule 1 daily cap for Berberis vulgaris, and how much berberine is in each gram of berry or bark is unknown.
• If you take prescription medicines, check with your doctor, pharmacist or our naturopaths before you start.