Ginkgo biloba has many health benefits. It’s often used to treat mental health conditions, Alzheimer’s disease, and fatigue. It’s been used in traditional Chinese medicine for about 1,000 years. It came on the Western culture scene a few centuries ago, but has enjoyed a surge of popularity over the last few decades.

Ginkgo is used as an herbal remedy to treat many conditions. It may be best known as a treatment for dementia, Alzheimer’s disease, and fatigue. Other conditions it’s used to treat are:

Like many natural remedies, ginkgo isn’t well-studied for many of the conditions it’s used for.

Ginkgo’s health benefits are thought to come from its high antioxidant and anti-inflammatory properties. It may also increase blood flow and play a role in how neurotransmitters in the brain operate.

Some studies support the effectiveness of ginkgo. Other research is mixed or inconclusive. In 2008, results of the Ginkgo Evaluation of Memory (GEM) study were released. The study sought to find out if ginkgo would reduce the occurrence of all types of dementia, including Alzheimer’s disease. It also looked at ginkgo’s impact on:

  • overall cognitive decline
  • blood pressure
  • incidence of cardiovascular disease and stroke
  • overall mortality
  • functional disability

The GEM study, the largest of its kind to date, followed 3,069 people age 75 or older for 6 to 7 years. Researchers found no effect for preventing dementia and Alzheimer’s disease in study participants who either took ginkgo or a placebo. And a 2012 meta-analysis found ginkgo had no positive effects on cognitive function in healthy people.

Still, a 2014 study showed ginkgo supplementation may benefit people who already have Alzheimer’s and take cholinesterase inhibitors, common medications used to treat the condition.

The GEM study also found ginkgo didn’t reduce high blood pressure. There was also no evidence ginkgo decreases the risk of heart attack or stroke. It may, however, reduce the risk of peripheral artery disease caused by poor blood circulation.

According to a 2013 systematic review, ginkgo can be considered an adjuvant therapy for schizophrenia. Researchers found ginkgo seemed “to exert a beneficial effect on positive psychotic symptoms” in people with chronic schizophrenia who take antipsychotic medication.

Researchers in that study also found positive study results for ADHD, autism, and generalized anxiety disorder, but indicated more research is needed.

According to an older review of evidence study, ginkgo may improve erectile dysfunction caused by antidepressant medications. Researchers believe ginkgo increases the availability of nitric oxide gas which plays a role in increasing blood flow to the penis.

Ginkgo may help relieve premenstrual syndrome (PMS) symptoms, according to a 2009 study. During the study, participants taking either ginkgo or a placebo experienced a reduction in symptoms. Those taking ginkgo had significantly more relief.

Ginkgo is generally safe for healthy people to use in moderation for up to six months. Severe side effects are rare. Still, the Food and Drug Administration (FDA) doesn’t regulate ginkgo and other over-the-counter herbal supplements as strictly as other drugs. This means it’s hard to know exactly what’s in the ginkgo you buy. Only buy a brand of supplement you trust.

Ginkgo may cause an allergic reaction in some people. Your risk may be higher if you’re allergic to urushiols, an oily resin found in poison ivy, sumac, poison oak, and mango rind.

Ginkgo may increase bleeding. Don’t use ginkgo if you have a bleeding disorder or take medications or use other herbs that may increase your risk of bleeding. To limit your bleeding risk, stop taking ginkgo at least two weeks before undergoing a surgical procedure.

Don’t take ginkgo if you’re on any medications that alter clotting. Don’t take it if you’re taking NSAIDS like ibuprofen, too. Ginkgo can have serious side effects. If you’re on any medication, let your doctor know the dose you plan on taking.

Ginkgo may lower blood sugar. Use with caution if you have diabetes or hypoglycemia or if you take other medications or herbs that also lower blood sugar.

Don’t eat ginkgo seeds or unprocessed ginkgo leaves; they’re toxic.

Due to the potential bleeding risk, don’t use ginkgo if you’re pregnant. Ginkgo hasn’t been studied for use in pregnant women, breastfeeding women, or children.

Other potential side effects of ginkgo are:

There was a time ginkgo seemed like a magic bullet for preventing age-related memory loss and other health conditions. But research to date doesn’t support much of the enthusiasm.

Most evidence for ginkgo is anecdotal or decades old. Still, research has shown ginkgo may slow the progression of Alzheimer’s disease, help treat some common mental health conditions, improve sexual function, and improve blood flow to the peripheral arteries.

Don’t replace a current medication with ginkgo or start taking ginkgo to treat a serious condition without consulting your doctor.