The herb has become popular as a supplement, with ginkgo extract touted as a way to keep memory sharp, as well as a remedy for a variety of health issues, such as anxiety, dementia, and heart disease, according to the NCCIH. Study results have been mixed, however, so additional research is needed to confirm these uses. Here’s a closer look at what ginkgo biloba is and what the available evidence indicates about using this ancient herb for health.
What Is Ginkgo Biloba?
Ginkgo is native to China and is one of the oldest living tree species on the planet. One ginkgo tree can live up to 1,000 years and grow to 120 feet tall, reports Mount Sinai. The tree consists of small branches with fan-shaped leaves, and it produces fruits that are not safe to eat, as their seeds may be poisonous. In traditional Chinese medicine, the ginkgo leaf itself was used as a natural health remedy, but today’s research focuses on ginkgo biloba extract made from dried leaves. Ginkgo extract is commonly available as an oral tablet, capsule, or tea, according to the Mayo Clinic. “Ginkgo contains high levels of flavonoids and terpenoids, which are compounds known for their strong antioxidant effects,” explains Kristine Dilley, a registered dietitian at The Ohio State University Wexner Medical Center in Columbus. “Antioxidants combat or neutralize the damaging effects of free radicals. Many of the suspected benefits of taking ginkgo are related to these antioxidant effects.” Here is what the available research shows about ginkgo biloba and the following applications.
Dementia and Cognitive Impairment
One of the most promoted benefits of ginkgo supplementation is that it helps treat and prevent dementia. Research in this area has yielded contradictory results, however. Findings about whether ginkgo can treat existing dementia have been contradictory, and there is also insufficient evidence to support using the herb for prevention, according to the National Library of Medicine. A study published in January 2017 in the Journal of Ethnopharmacology analyzed 12 systematic reviews and concluded that ginkgo has potentially beneficial effects for people with dementia when taken for at least five months. Another systematic review of nine trials found that ginkgo was linked to a slowed decline in cognition, function, and behavior in people with dementia. Dilley notes that these positive results in improvement in function are believed to be related to increased blood circulation in the brain. A separate review of studies published in January 2018 in the Annals of Internal Medicine found that there’s no evidence to support the use of over-the-counter supplements, including ginkgo biloba, to prevent or delay cognitive decline. “Consumers should be aware that while some studies have shown effectiveness, not all studies have shown a benefit, and further research is needed,” Dilley says.
Heart Disease
Some research suggests that gingko may have a positive impact on cardiovascular disease. A study published in December 2017 in the journal Stroke and Vascular Neurology looked at 348 people in China with onset of acute ischemic stroke. Around half of the participants adhered to a treatment plan of daily ginkgo and aspirin, while those in the other group were given aspirin alone. After six months, the researchers found that the group taking aspirin in combination with ginkgo fared better, with lessened cognitive and neurological impairment without increasing the incidence of vascular events. Another study found that taking ginkgo was linked to improved blood circulation in people with coronary artery disease. Other trials, however, found no benefit from ginkgo for people with heart disease. More large clinical trials are needed to fully understand the effects of ginkgo on cardiovascular disease.
Depression and Anxiety
A small body of research suggests that ginkgo may play a role in treating psychiatric disorders like depression and anxiety. A study published in September 2018 in the journal Medicine concluded that ginkgo, as an adjunctive (added) treatment to a selective serotonin reuptake inhibitor could help improve depressive symptoms and cognitive function. Another study found that people with generalized anxiety disorder who took ginkgo had better relief from anxiety symptoms than those who took a placebo. Ultimately, more rigorous research is needed in this area to determine the potential effects of ginkgo on mental health.
Sexual Dysfunction
Some small studies have suggested that ginkgo shows promise in improving sexual dysfunction, but again, further research is needed. An older study found that extract of the gingko leaf was 84 percent effective in treating antidepressant-induced sexual dysfunction. Another study concluded that a nutritional supplement containing ginkgo, along with a number of vitamins and minerals, led to significant improvement in sexual desire in premenopausal, perimenopausal, and postmenopausal women when compared with a placebo. “Any individual taking prescription medications should always check with their physician or pharmacist prior to taking herbal supplements as there could be a chance for adverse reactions,” Dilley says. “Ginkgo may interact with some conventional medications, including anticoagulants (blood thinners), nonsteroidal anti-inflammatory drugs, and antidepressants, and should not be taken without the approval of your physician.” While the research on its benefits is mixed, ginkgo appears to be safe and well tolerated in modest amounts, according to the Mayo Clinic. So if you get the go-ahead from your doctor, there will likely be no harm in giving it a try. It’s important to keep your expectations in check, however, advises Alice Sullivan, DO, a functional medicine specialist at the Cleveland Clinic. “A lot of the ways that ginkgo has been studied, such as for improvement of vascular illness or memory impairments, or brain health, these conditions are multifactorial, and just bringing in one agent isn’t really going to improve your outcome,” she says. Rather, when Dr. Sullivan sees patients with one of those conditions, she might advise using ginkgo “as one tool in the arsenal,” she says, in addition to lifestyle changes and any medication they’ve been prescribed. When it comes to dosage, there is no standard dose or prescribed upper limit for gingko. “In studies, doses are typically between 120 to 240 milligrams per day in divided doses,” Dilley says. “It may take up to four to six weeks before effects are noticed.” “Gingko might cause early labor or extra bleeding during delivery if used near that time, and effects during breastfeeding are unknown,” she explains. Ginkgo can increase the risk of bleeding, so it is not recommended for people taking anticoagulants, or blood thinners, Sullivan notes. For the same reason, the Mayo Clinic recommends that you stop taking ginkgo two weeks before surgery. Ginkgo may also interfere with the management of diabetes and seizure medications, so it is not recommended for people with these conditions, according to Mount Sinai. According to the Mayo Clinic, side effects of taking ginkgo can include:
HeadacheDizzinessUpset stomachConstipationHeart palpitationsAllergic skin reactions
“Federal law does not require dietary supplements to go through the same standards of premarket testing for safety or efficacy as drugs intended to treat disease,” Dilley says. She advises that consumers look for products that are certified by a third party to ensure that the product contains what it claims and not other (potentially harmful) substances. If you’re having trouble determining which brands of ginkgo supplements to use, ask your healthcare provider for recommendations.
