Berberine for weight loss: what the evidence shows in Australia

Berberine may help with weight loss, but the effect is small: across randomised trials, people taking it lost about 1 to 2 kg more than people who did not. The trials were short and many were small. Berberine interacts with several medicines and is not safe in pregnancy, so check with your GP or pharmacist before you try it.

Three systematic reviews have pooled the berberine weight trials. They agree on the direction and differ on the size. Here is what each one found.

What is berberine?

Berberine is a bitter yellow compound found in plants such as barberry (Berberis), goldenseal and Chinese goldthread (Coptis chinensis). It has a long history in traditional Chinese and Ayurvedic medicine, mostly for gut infections.

Modern interest comes from its effects on metabolism. In lab studies, berberine switches on AMPK, an enzyme that works as a cell's fuel gauge and nudges cells to take up glucose and burn fat. A 2019 review in Theranostics (Feng et al.) summarised trials testing it for cholesterol, blood glucose and fatty liver, at doses of 0.5 to 2.0 g a day for 4 to 24 weeks.

Berberine is also poorly absorbed. The same review notes that it clumps together in the gut and is pumped back out of gut cells, so only a small fraction reaches the blood. That is one reason products and results vary so much.

Does berberine work for weight loss?

Berberine produces a small average weight loss in trials, roughly 1 to 2 kg over a few months. That is real, but it is modest, and the quality of the evidence is mixed.

• Asbaghi 2020 pooled 12 randomised trials. Body weight was 2.07 kg lower with berberine, BMI 0.47 points lower and waist 1.08 cm smaller. CRP, a marker of inflammation, also fell a little. Liver enzymes did not change.
• Xiong 2020 pooled 10 studies. BMI fell by 0.29 points and waist by 2.75 cm, but the change in body weight (0.11 kg) was not statistically clear.
• Elahi Vahed 2026, the largest, pooled 23 trials. Weight fell by 0.88 kg, BMI by 0.48 points and waist by about 1.3 cm. Waist-to-hip ratio did not change.

The authors of the 2026 review flagged the problems themselves. Many trials did not report the purity, potency or exact amount of berberine in the product, and many had weak blinding or randomisation. Trials ran for weeks to months, so we do not know what happens over years, or whether the weight stays off.

“The health system doesn't focus on health. Lifestyle is the root cause of health. Most chronic diseases are lifestyle driven.”
Dr Michelle Woolhouse, Vively Medical Director

Berberine dosage in trials

Clinical trials have used 0.5 to 2.0 g of berberine a day, usually split into two or three doses with meals, for 4 to 24 weeks. Taking it with food is how most trials did it and may reduce stomach upset.

We do not give dosing advice for supplements. Follow the directions on the product, and ask your GP or pharmacist whether it suits you, especially if you take any regular medicine. More is not better: higher doses mostly bring more gut side effects.

Is berberine safe? Side effects and interactions

Berberine is usually well tolerated for short periods, but it is not risk-free. The US National Center for Complementary and Integrative Health lists stomach pain, constipation, diarrhoea, nausea and vomiting as the most common side effects.

Who should not take berberine

• Pregnancy and breastfeeding: NCCIH advises against berberine. It can cause or worsen jaundice in newborn babies and could lead to kernicterus, a rare but serious brain injury.
• Babies and young children: for the same reason.
• People taking cyclosporin: in kidney transplant recipients, berberine raised blood levels of cyclosporin, a transplant medicine (Wu 2005).

Medicine interactions

Berberine slows several of the liver enzymes that clear medicines. In healthy men taking 300 mg three times a day for two weeks, it reduced the activity of CYP2D6, CYP2C9 and CYP3A4 (Guo 2012). Those enzymes clear many common medicines, such as some antidepressants, blood pressure tablets, statins and blood thinners, so levels of those medicines can rise.

Because berberine is taken to lower blood glucose, combining it with metformin, insulin or other diabetes medicines could add to their effect and raise the risk of low blood glucose. If you take any glucose-lowering medicine, talk to your GP before starting berberine. Our guides to metformin for weight loss and weight loss medication in Australia cover the prescription options.

Berberine in Australia: how it is regulated

Most berberine products sold in Australia are listed medicines on the Australian Register of Therapeutic Goods (ARTG). You can tell by the AUST L number on the pack.

Listed (AUST L) medicines can contain only pre-approved low-risk ingredients and must be made to quality standards, but the TGA does not evaluate whether they work before they go on sale. The company has to hold evidence for its claims. Registered (AUST R) medicines, including prescription medicines, are assessed for effectiveness as well as safety and quality.

So an AUST L number tells you the product is legally supplied. It does not tell you it will help you lose weight. If a berberine product promises dramatic weight loss, or calls itself "nature's Ozempic", treat that as marketing.

What is the best berberine supplement in Australia?

We do not recommend brands. When you compare products, look for an AUST L or AUST R number, the amount of berberine (often as berberine hydrochloride) per capsule, a batch number and expiry date, and directions that match what trials used. Combination products with several herbs make it harder to know what you are taking. Our guide to supplements for blood sugar covers the other options people ask about.

Check your insulin before you reach for a supplement

Most people looking at berberine want help with weight that will not shift, cravings or creeping blood glucose. Insulin resistance often sits behind all three, and it can be there for years while blood glucose still reads normal.

Among 4,579 Vively members whose HbA1c and fasting glucose were both inside the lab range, 57% had fasting insulin above our optimal range of 3 to 5 mIU/L. Find where you sit for your age and sex below.

“Insulin moves decades generally... the thinking is around 10 to 15 years before glucose does. That's how much the body works to try and keep homeostasis intact.”
Dr Michelle Woolhouse, Vively Medical Director

A raised fasting insulin or HOMA-IR is an early warning you can act on. The changes that bring it down are everyday ones: more fibre and protein, fewer refined carbohydrates, regular movement, strength training and enough sleep. We explain the test in why fasting insulin is the best early test, and how to lose weight with insulin resistance sets out the plan.

Testing also tells you whether anything you try is working. If you do take berberine with your GP's OK, measure before and after rather than relying on the scales alone.

How Vively can help

The Vively membership is $99 a month. It starts with the Baseline, a blood test covering 70+ markers, including fasting glucose, fasting insulin, HbA1c and cholesterol, read against optimal ranges. A practitioner explains your results, dietitian coaching is available through the membership, and your membership includes a targeted re-test after 3 months, so you can see whether your changes are moving the numbers. If you want to watch your glucose day to day, our CGM program shows how meals, sleep and movement affect it.

Frequently asked questions

Does berberine really work for weight loss?

A little. In meta-analyses of randomised trials, people taking berberine lost on average about 0.9 to 2.1 kg more than control groups, and one review found no clear difference in weight, only in BMI and waist. The trials were short and of mixed quality, so berberine is no substitute for changes to food, movement and sleep.

What dosage of berberine should I take for weight loss?

Trials used 0.5 to 2.0 g a day, usually split into two or three doses with meals, for 4 to 24 weeks. We do not give supplement doses. Follow the product directions and check with your GP or pharmacist first, especially if you take any medicine or have diabetes.

What is the best berberine for weight loss in Australia?

No brand has shown better weight loss than another, and we do not recommend brands. Choose a product with an AUST L or AUST R number that states the amount of berberine per capsule. An AUST L number means the product is legally listed, not that the TGA has checked it works.

Can you take berberine with metformin?

Only with your doctor's advice. Both lower blood glucose, so together they may add to each other's effect and raise the risk of lows, and berberine also slows liver enzymes that clear other medicines. Never stop or change a prescribed medicine to take berberine instead.

Is berberine safe to take every day?

Berberine is usually well tolerated in short trials, with stomach upset, constipation and diarrhoea the common side effects. It is not safe in pregnancy or breastfeeding and interacts with medicines such as cyclosporin and others cleared by CYP liver enzymes. Long-term safety data are limited.

Sources

1. Asbaghi O et al. The effect of berberine supplementation on obesity parameters, inflammation and liver function enzymes: a systematic review and meta-analysis of randomized controlled trials. Clin Nutr ESPEN 2020;38:43-49.
2. Xiong P et al. The effect of berberine supplementation on obesity indices: a dose-response meta-analysis and systematic review of randomized controlled trials. Complement Ther Clin Pract 2020;39:101113.
3. Elahi Vahed I et al. The effect of berberine on obesity indices: a systematic review and meta-analysis. Int J Obes 2026;50(1):53-73.
4. Feng X et al. Berberine in cardiovascular and metabolic diseases: from mechanisms to therapeutics. Theranostics 2019;9(7):1923-1951.
5. National Center for Complementary and Integrative Health. In the news: berberine. Updated June 2023.
6. Wu X et al. Effects of berberine on the blood concentration of cyclosporin A in renal transplanted recipients. Eur J Clin Pharmacol 2005;61(8):567-572.
7. Guo Y et al. Repeated administration of berberine inhibits cytochromes P450 in humans. Eur J Clin Pharmacol 2012;68(2):213-217.
8. Therapeutic Goods Administration. How we regulate medicines.