Berberine: Benefits, Dosage and Side Effects

Berberine, a compound found in certain plants, is known for its deep yellow color and has frequently been used throughout history as a natural dye for wood, leather and wool. Berberine is also used in traditional Chinese medicine and has been studied for its potential benefits for heart health, lowering blood sugar and use as an antibacterial.

Here, we’ll explore these and more potential benefits of berberine and yellow root, along with dosage recommendations and side effects of berberine supplements.

Berberine is a compound found in a variety of plants, including European barberry, goldenseal (yellow root), goldthread, Oregon grape, phellodendron (not be confused with the house plant philodendron) and tree turmeric, according to the Memorial Sloan Kettering Cancer Center.

“These berberine-containing plants have a long history of treating infections throughout the centuries,” says Patrick Fratellone, MD, an integrative cardiologist with Fratellone Medical Associates.

Berberine is not typically found in the foods we eat, but it is sold as a supplement, says Christy B. Williamson, DCN, CNS, doctor of clinical nutrition and CEO of the Nutritional Genomics Institute. These supplements are most commonly said to help lower cholesterol and manage blood sugar for people with type 2 diabetes.

Williamson adds that berberine may help reduce inflammation and ward off bacterial infections. And it has been studied for heart failure and used for thousands of years as a treatment for diarrhea in China, according to the National Center for Complementary and Integrative Health (NCCIH).

Yellow root, also known as goldenseal, is a plant native to North America that was used by Native Americans and later, European settlers, for treating ailments like skin disorders, fevers and ulcers.

Yellow root is a small plant with a hairy stem, jagged leaves, small flowers and raspberry-looking fruit, and it contains a small amount of berberine. Yellow root can be found in tea, liquid extract, tablet and capsule form. It is also often combined with other herbs such as echinacea.

While it may have some helpful properties, the NCCIH explains that when people take yellow root by mouth — like in a pill supplement or yellow root tea — very little of the berberine actually enters the bloodstream. Because of this, it’s difficult to study the exact effect of berberine on the body from yellow root alone.

Additionally, goldenseal can interfere with how a blood sugar medication called metformin—most commonly used by people with type 2 diabetes to lower blood sugar — is processed in the body, so yellow root is not recommended for people taking oral blood sugar medication.

Dr. Fratellone says he has used berberine plants to treat urinary tract infections and that it is also commonly used for GI problems, circulatory issues, liver diseases and bronchial ailments. “I recommend berberine to most of my patients with diabetes, arthritis and even heart disease,” he notes.

Additionally, there have been quite a few studies done on the potential benefits of berberine. They include:

Berberine has been found to help regulate blood sugar and lipid metabolism. According to a September 2015 review in ​Science China Life Sciences​, it’s thought that berberine has an effect on blood sugar because it increases the receptivity of insulin cells, helping them work more effectively.

This is why berberine may be effective in treating people with polycystic ovary syndrome, many of whom struggle with insulin resistance or diabetes. It may also help reduce androgen levels, which can improve ovulation, according to The National Polycystic Ovary Syndrome Association.

An older but often-cited May 2008 study in ​Metabolism​ looked at a relatively small sample size of 36 adults newly diagnosed with type 2 diabetes who were treated with either berberine or metformin (both three times per day) over the course of three months. The study concluded that both methods had a similar effect on lowering blood sugar.

However, an October 2012 systematic review and meta-analysis on the topic, published in ​Evidence-Based Complementary and Alternative Medicine​, noted that, yes, berberine seems to help bring down high blood sugar, but the evidence for its use as a treatment for type 2 diabetes is still very limited and of low quality.

The same 2008 ​Metabolism​ study found that the group of people who took berberine saw other benefits in addition to regulating blood sugar, including lowering their total cholesterol and low-density lipoprotein (LDL, or “bad”) cholesterol.

According to the ​Science China Life Sciences​ review, there hasn’t yet been a large-scale, randomized, double-blind clinical trial on how berberine can lower cholesterol, but the researchers pointed to a number of independent groups that have documented this effect. The paper notes that berberine can reduce total cholesterol by up to 31 percent, LDL by up to 25 percent and triglycerides by up to 35 percent. It’s also been reported that berberine can raise HDL, the “good” cholesterol.

The Memorial Sloan Kettering Cancer Center notes that berberine may be most effective in people who have mild cases of high cholesterol, but it won’t take the place of healthy, cholesterol-lowering lifestyle habits like getting regular exercise and eating nutritious food.

Berberine is helpful as a tool for supporting heart health because it has properties that help combat high blood pressure, high cholesterol, arrhythmias and blood clots, according to a December 2015 paper in ​Chronic Diseases and Translational Medicine​.

Indeed, a January 2017 report in ​Clinical Lipidology​ explains that berberine was found to reduce blood lipid levels (fat levels in the blood) in people with type 2 diabetes, high cholesterol and fatty liver disease. It was also found to help dilate blood vessels and make them more elastic, thus lowering blood pressure and preventing against blood vessel disease.

Again, though, berberine is most effective in supporting heart health alongside other interventions, such as leading a healthy lifestyle.

Some research suggests berberine can help some people manage their weight. For instance, a July 2020 systematic review in ​Biomedicine & Pharmacotherapy​ on the effect of berberine on weight loss found that berberine can help prevent obesity in a few different ways: by changing the genes that make the body store fat, helping to stop the growth of fat in the body by encouraging enzymes that activate glucose and fatty acid uptake and regulating gut hormones, which also impact weight and insulin resistance.

Another study, published July 2012 in ​Phytomedicine​, confirmed that berberine can be helpful for weight loss: Study participants lost an average of 5 pounds after taking 500 milligrams of berberine three times a day for 12 weeks. They also improved other health markers, including lower cholesterol levels.

In a May 2014 study conducted on mice in ​Clinical Microbiology​, researchers found giving a berberine supplementation for 14 weeks significantly decreased inflammatory markers and helped protect the spleen, liver and kidney from the effects of chronic inflammation. However, these findings can’t necessarily be extended to humans.

The same study in ​Clinical Microbiology​ also found that berberine could help fight off bacteria when used in conjunction with antibiotics. Essentially, berberine might disrupt the stability of the biofilm that bacteria forms to do its dirty work (think of bacteria joining together to create a sort of sticky plastic wrap — that’s what the biofilm is like).

By disrupting that biofilm, the berberine can then allow antibiotics to more effectively kill off bacteria. This is also why some people tout berberine as a supplement to strengthen the mucous membrane.

Again, though, this study was done in rodents, so we don’t know if berberine would have the same effect in humans.

How much berberine you should take depends on what you want it to do for you. Williamson says the following recommended dosages have been based off various studies:

• ​For diabetes management:​ 500 mg before or after each meal for a total of 1,500 mg per day
• ​For high cholesterol and heart disease:​ 1,000 mg per day
• ​For weight loss:​ 500 mg per day
• ​As an antioxidant/anti-inflammatory:​ 300 mg per day

Note that you should always talk to your doctor first before adding any supplement to your regimen.

Whenever possible, Williamson recommends taking berberine in smaller dosages several times per day to decrease the risk of side effects.

The side effects that can occur with berberine are overall pretty mild, but can include:

• Appetite loss
• Upset stomach
• Diarrhea
• Constipation
• Skin rash

However, always be sure to talk to your doctor before taking berberine or yellow root because it can interfere with certain conditions and medications.

While Dr. Fratellone notes that there are no major known side effects to using berberine-containing plants, he does warn that higher doses can exacerbate shortness of breath. “I would use caution in giving it to a child with severe asthma,” he says.

“While berberine is generally considered safe, long-term use depends on the individual and condition that is being treated,” Williamson adds. “Most studies have only followed use for up to six months, so there currently isn’t enough data on long-term use. It is important to discuss long-term use with a qualified health care professional.”

You should not take berberine if you are:

• ​Pregnant or breastfeeding.​ Berberine can lead to jaundice in babies and brain disorders, and it may cause miscarriage.
• ​Taking tacrolimus or cyclosporin​, which are immune-suppressing drugs. Berberine can increase the levels of both of those drugs in your body, which can
  cause kidney toxicity.
• ​Taking sulfonylureas​, a medication for diabetes.
  It’s thought that berberine may interfere with the metabolism of this drug.
• ​Taking certain antibiotics like azithromycin or other macrolide antibiotics​. There can be serious side effects like cardiotoxicity, warns Williamson.
• ​Taking CYP2D6, 2C9 or 3A4 substrate drugs.​ Berberine may cause these medications to be
  less effective.
• ​On warfarin (Coumadin) for blood clots​, as berberine can increase the
  levels of the medication in. your blood, according to the December 2015 paper in ​Chronic Diseases and Translational Medicine​.