Can You Take Berberine and Metformin Together for Weight Loss?

Glucagon-like peptide-1 (GLP-1) medications like Ozempic and Wegovy have changed how people think about weight loss. But not everyone wants to use medications, and some people are looking for more affordable or “natural” options.

One supplement that’s gained attention online is berberine — sometimes called “nature’s Ozempic.” In particular, some people believe taking berberine with metformin, a common diabetes medication, could lead to even more weight loss.

Here’s what the science says about combining berberine and metformin for weight loss, as well as whether the reported benefits are worth the possible risks and side effects.

What are berberine and metformin?

Metformin is a prescription medication that’s FDA approved to treat Type 2 diabetes. Healthcare professionals also sometimes prescribe it off-label for conditions linked to metabolism and insulin resistance, like: 

• Diabetes 

• Polyendocrine metabolic ovarian syndrome (PMOS) — formerly called polycystic ovary syndrome (PCOS)

Berberine is a naturally occurring compound found in plants such as tree turmeric, barberry, and Oregon grape. It’s sold as an over-the-counter (OTC) dietary supplement and has been used in traditional medicine practices for centuries.

Neither metformin nor berberine is FDA approved for weight loss.

Unlike prescription medications, dietary supplements aren’t reviewed by the FDA for safety and effectiveness before they’re sold. This means the quality and amount of berberine can vary between products.

How do berberine and metformin work for weight loss?

Metformin and berberine seem to affect metabolism in some similar ways. Both may help lower blood sugar and influence how the body stores and uses energy. But they aren’t interchangeable.

Can you take berberine and metformin together for weight loss?

There’s not enough research to know whether combining berberine and metformin leads to more weight loss than taking metformin alone.

Since berberine and metformin can both affect blood sugar and cause digestive side effects, taking them together may increase the risk of problems such as:

• Diarrhea

• Bloating and gas

• Upset stomach

• Low blood glucose (hypoglycemia)

The risk of low blood glucose may be higher if you also take other diabetes medications. So talk with a healthcare professional before taking berberine and metformin together, especially if you have diabetes. 

How effective are berberine and metformin for weight loss?

Overall, metformin has stronger evidence for safety and effectiveness than berberine. 

Metformin can lead to modest weight loss in some people, especially those with Type 2 diabetes or obesity. Studies suggest that people taking metformin may lose a small amount of body weight over time, about 6 lbs to 8 lbs. But the effects are generally smaller than with FDA-approved weight-loss medications.

There’s some evidence that berberine may have small effects on the following in people with Type 2 diabetes:

• Body weight

• Waist circumference

• Cholesterol

• Blood glucose levels 

But researchers need higher-quality studies in humans to say for sure.

How long can you take berberine or metformin for weight loss?

Many people take metformin long-term to help manage Type 2 diabetes. Your prescriber can help determine whether you should continue taking metformin and whether it’s right for your health needs.

Researchers still don’t know much about the long-term safety or effectiveness of berberine for weight loss. Some studies have followed people taking berberine for several months, but long-term data is limited.

There also aren’t official dosage guidelines for berberine. But most studies used total doses between 500 mg and 1,500 mg per day, divided into 3 separate doses.

What are the risks and side effects of combining berberine and metformin?

Berberine and metformin can cause similar digestive side effects. Taking them together may make these side effects more likely.

Common side effects may include:

• Diarrhea

• Constipation

• Bloating and gas

• Upset stomach

• Nausea

Metformin rarely causes low blood glucose on its own. But because berberine may also lower blood sugar, combining the two could increase the risk of hypoglycemia — especially if you take other diabetes medications.

Some people should avoid berberine altogether. You should avoid berberine if you’re pregnant or breastfeeding. Berberine may also interact with certain medications, including some diabetes medications and immunosuppressive medications. And remember: Because berberine is a dietary supplement, the actual amount of berberine in a product may differ from what the label says.

Your healthcare team or pharmacist can help review your medications and determine whether berberine is safe for you.

What are the best alternatives to berberine and metformin for weight loss?

Berberine and metformin aren’t the only options for weight loss.

Long-term lifestyle changes — such as regular physical activity and nutrition changes — can still play an important role in weight management.

Healthcare professionals may also recommend FDA-approved weight-loss medications for some people. These include GLP-1 medications as well as other weight-loss medications.

If weight loss is a health goal for you, talk with a healthcare professional about the safest and most effective options for your health needs.

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Written by:

Hindu Rao, PharmD, APh, BCACP

Hindu Rao, PharmD, APh, BCACP is a clinical assistant professor of pharmacy practice at Chapman University School of Pharmacy and a clinical pharmacist at Providence Medical Foundation. She specializes in chronic disease management and has her board certification in ambulatory care.

Edited by:

Sophie Vergnaud, MD

Sophie Vergnaud, MD, is the Senior Medical Director for GoodRx Health. A pulmonologist and hospitalist, she practiced and taught clinical medicine at hospitals in London for a decade before entering a career in health education and technology.

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