What Are the Benefits and Side Effects of Taking the Herb Supplement Berberine?

Berberine is an alkaloid compound naturally found in shrubs in the Berberis (barberry) family. Benefits of berberine include better blood sugar control and less PCOS symptoms and side effects include digestive symptoms and jaundice.

Berberine is a compound found in plants. It might benefit heart health and metabolic diseases like type 2 diabetes, but experts say you also need to make lifestyle changes.

Berberine is an alkaloid compound naturally found in shrubs in the Berberis (barberry) family. Many plants contain berberine, including barberry, goldenseal, Oregon grape, tree turmeric, and Chinese goldthread. Berberine has a bitter taste and a yellow color and is commonly used as a dye.

Berberine and plants containing berberine are commonly used in Ayurveda, traditional Chinese medicine, and other healing systems. It’s a popular remedy for diarrhea, infections, and inflammation. It’s often also used for high blood pressure, type 2 diabetes, and high blood fat levels. 

Today, companies market berberine supplements for similar health benefits. Most of the research on these claims isn’t of rigorous quality, but it shows that berberine is bioactive. This means it affects your body and can impact your health. 

It’s not clear yet whether supplements are a good idea because humans don’t absorb berberine very well. It doesn’t dissolve easily  in water, it doesn’t easily cross into your cells, and your body eliminates it quickly. 

Some early animal studies suggest that only half of a dose of berberine is absorbed through your gut while you get rid of the rest. These studies suggest low amounts end up in your blood. 

Companies have tried to change the structure of berberine to make it more absorbent and effective. These products are sometimes called berberine derivatives or analogs. These changes might help, but for some problems, the analogs only work well if they aren’t modified too much. There isn’t a simple solution yet. 

Despite its limits, berberine might have some health benefits. More research is necessary, though. 

Antimicrobial

In China, berberine is a common over-the-counter drug for treating gut infections. Studies show it’s effective against many disease-causing microbes, including bacteria.

Some lab dish studies show that berberine can damage the proteins of group B streptococcus bacteria. Depending on the dose, berberine could kill all the bacteria in the lab dish within four hours. The researchers suspect berberine can also block bacteria from synthesizing or processing DNA, which would slow their growth.

Other studies show that berberine alone might not be a very strong antimicrobial. They might work better alongside other compounds or plants. 

Blood sugar control

Berberine is commonly used and marketed to control blood sugar and type 2 diabetes. Type 2 diabetes happens when your body becomes resistant to insulin. This resistance occurs in your muscles, liver, and fat cells, and later in the beta-cells that make insulin. 

Insulin helps your cells convert glucose, or sugar, from your food to make energy. When you can’t use insulin properly, your body can’t use glucose properly either, and it can build up in your blood. 

Experts first reported that berberine could lower blood sugar in 1986. In a three-month trial, berberine had similar effects to an anti-diabetes drug called metformin. Berberine could lower blood glucose levels and other diabetes markers. 

Since then, more studies have been done, but most are of poor quality. Some reviews of study results suggest that berberine might work better as a short-term treatment or if you’re younger. Other results show it might improve your heart health, which could have a secondary effect on diabetes and metabolic disease. 

Might help IBS

Berberine might help digestive symptoms. In one study, patients with irritable bowel syndrome (IBS) received berberine tablets or a placebo pill twice a day for eight weeks. After a four-week break, they found that those who took the berberine had lower IBS symptoms than those who didn’t. 

The test subjects also had a better quality of life score and lower anxiety and depression. The study was small, so more research is necessary to confirm the results. 

Might lower colon cancer risk

There are a few studies on the effects of berberine on cancer; some show it might have anti-cancer activities. Berberine blocks the growth of some cancer cells by blocking protein enzyme signaling and free radicals. 

Early studies also indicate berberine has anti-tumor effects, can promote tumor cell death, and can suppress cell spread. In a study of 1000 patients, berberine appeared to lower the risk of benign colon and rectal tumors returning in the test group compared to those in the control group. The study suggests that berberine could help reduce the risk of colon cancer after surgery to remove growths called polyps.

Might help PCOS 

Polycystic ovary syndrome, or PCOS, is a reproductive and metabolic disorder where your ovaries make more male hormones than normal. It’s not clear what causes PCOS, but it might be related to insulin resistance.

When your body doesn’t use insulin properly, your body responds by making more insulin. Excess amounts can cause your body to produce more male sex hormones called androgens.  

One small study of patients with PCOS compared berberine to metformin and to a placebo pill. After three months, those who had the berberine had lower waist measurement, waist-to-hip ratio, cholesterol, blood fat levels, and higher levels of a protein that binds sex hormones. Compared to the placebo group, they also had lower fasting glucose and insulin. 

Berberine improved some of the metabolic and hormonal markers of PCOS. Researchers felt the effects of berberine were probably due to changes in body composition. The study was small, though, so more research is necessary.  

Might improve heart health

Atherosclerosis is a condition that happens slowly when fat, cholesterol, and blood cells form plaque in your blood. The plaque builds up and causes your arteries to narrow, which blocks blood flow to your organs and tissues. Atherosclerosis in the arteries of your heart is called coronary artery disease. 

Studies show that berberine is anti-atherosclerotic, which means it stops plaque from building up in your arteries. Some data suggest berberine can improve blood fat levels in those with coronary artery disease who don’t respond to statin medications. 

A combination of berberine and red yeast rice also lowered bad cholesterol and blood fat levels in patients with heart disease. Experts feel that the evidence for berberine is limited, but it might help if it’s used alone or as part of a combination supplement. 

Berberine might help prevent heart disease. It might work best when you have a mild case of high cholesterol that doesn’t respond to statins or metabolic syndrome. 

Might improve fatty liver disease

Nonalcoholic fatty liver disease, or NAFLD, happens when fat builds up in your liver. It’s not clear exactly why it happens, but it’s linked to insulin resistance, high blood sugar, and high blood fat levels.

In a small study, NAFLD patients were randomly assigned adopted lifestyle changes and either berberine or medication as treatment. After four months, those who had the lifestyle changes plus berberine had lower liver fat content, blood fats, and better insulin response. Berberine worked better at lowering body weight and blood fats than the medication.

Experts think berberine might help your liver break down fat. Based on this research, it’s likely that it works best alongside lifestyle changes. 

Berberine is safe when you take it by mouth. A dose of 1.5 grams daily for up to six months is likely safe for adults, though you should ask your doctor first. Berberine is well-tolerated, but some side effects are possible. 

Digestive symptoms

The most common side effect of berberine supplements is digestive issues. Berberine commonly causes diarrhea, constipation, upset stomach, and loss of appetite. It can cause a rash, too.  

Might worsen jaundice in babies

Berberine is likely unsafe for children and might worsen jaundice in babies. Don’t take berberine if you’re pregnant or breastfeeding, as it can pass to your baby and cause liver problems. Berberine might cause prolonged high bilirubin levels, which can cause permanent damage and a condition called kernicterus. 

Interacts with medication

Like many other herbs and supplements, berberine can interact with medications and other supplements. 

CYP substrates are medications your body breaks down and changes in your liver. Because of their effects on the liver, berberine might change how quickly your liver breaks these down. Your medications might not work as usual, and you might experience some side effects.

Berberine can also lower blood pressure and blood sugar and slow blood clotting. If you take blood thinners, anti-diabetes, or blood pressure medication, berberine might make these effects too strong. 

Berberine can also interact with sedatives, phenobarbital, cyclosporine, and other medications. It can strengthen some medications and cause serious side effects. 

The research on berberine suggests some health benefits. It can interact with some medications and cause serious side effects, though. Talk to your doctor and your pharmacist before you take berberine.