Ginkgo Biloba: Benefits, Safety, and Dosage

Ginkgo biloba, also known as the maidenhair tree, is one of the oldest living tree species in the world. It is native to China, where its seeds have been used for centuries in traditional Chinese medicine to help improve cognitive health and treat asthma, bronchitis, and kidney and bladder disorders.

Today, ginkgo biloba, the extract made from the tree's dried leaves, is widely available in supplement form. While research is limited, there is some evidence that ginkgo extract may help improve symptoms of dementia and enhance blood flow.

This article discusses the potential benefits and uses of ginkgo biloba. It also covers the risk factors and side effects of taking ginkgo biloba supplements.

Potential Benefits of Ginkgo Biloba

Further studies are needed to confirm the health benefits of ginkgo biloba. However, it appears to be most effective for cognitive health. The herb may also help protect against cell damage, support eye health, and improve blood flow.

May Reduce Symptoms of Dementia

Ginkgo biloba has been used for years to treat memory loss, cognitive decline, and decreased alertness.

Preliminary research suggests it may help improve symptoms of dementia, which is a progressive impaired ability to think, remember, and make decisions, which interferes with performing daily activities.

A 2020 mini-review of studies on ginkgo biloba found that taking at least 240 milligrams (mg) of the leaf extract daily for more than 24 weeks may improve cognitive function in people with mild dementia. Shorter-term use with lower doses did not show significant benefits.

Similar cognitive improvements were also seen in a 2023 pilot study involving older adults with mild to moderate stroke. However, the study received funding from a pharmaceutical company, raising concerns about potential bias.

Still, the beneficial effects of ginkgo biloba are thought to be partially due to the herb's ability to increase blood flow to the brain.

While research appears promising, further long-term studies are needed to confirm its effectiveness. Additionally, there is no solid evidence to suggest that ginkgo biloba can prevent dementia, cognitive decline, or the progression of Alzheimer's related-dementia.

Rich in Antioxidants

Ginkgo biloba leaves are a rich source of flavonoids and terpenoids with potent antioxidant activity.

Antioxidants are compounds that prevent or delay damage caused by free radicals.

Free radicals are harmful, unstable molecules produced during normal cell division that can disrupt many natural processes in the body, including breathing and digesting food. External factors like exposure to sunlight and cigarette smoke can also lead to the production of free radicals.

When free radicals build up, they can lead to cell damage and health problems.

May Improve Eye Health

While further studies are needed, ginkgo biloba extract appears to be a promising treatment for age-related eye diseases.

A 2013 review of two small studies on people with age-related macular degeneration suggested possible improvement in vision after six months of ginkgo biloba administration.

In addition, ginkgo biloba is a popular alternative treatment for glaucoma, a progressive eye disease that damages the optic nerve leading to vision loss.

A 2013 observational study on 42 people with normal tension glaucoma reported vision improvements with 80 mg of ginkgo biloba extract administered orally twice daily over four years.

However, a 2014 randomized control trial in 35 patients found no significant improvement in vision after being treated with ginkgo biloba.

Its positive effects on vision are thought to be primarily due to its antioxidant and anti-inflammatory properties and its ability to improve blood flow to the eye and protect neurons from damage.

More extensive studies are needed to understand the effects of ginkgo biloba on eye health.

May Benefit Heart Health and Circulation

The flavonoids and terpenes in ginkgo biloba have strong antioxidant and anti-inflammatory properties, which can benefit heart health. Furthermore, the herb's potential ability to improve blood flow and reduce blood pressure may positively affect heart health.

Ginkgo biloba seems to be most effective when combined with traditional therapies.

A 2015 systematic review of 23 randomized control trials involving 2,529 people found that, when combined with routine medicine, ginkgo biloba extract was more effective at relieving angina pectoris than routine medicine alone.

Angina pectoris, or stable angina, is chest pain or discomfort caused by heart disease. It occurs when there is inadequate blood supply to the heart.

It is important to mention, however, that most of the studies supporting the use of ginkgo biloba for blood pressure reduction have been conducted in rats. Human studies have produced mixed results.

As such, it is not known for certain if these same effects will occur in humans.

May Improve Depression

There is growing evidence that ginkgo biloba may be effective at improving depression.

One 2018 study in 136 adults 60 and older with depression showed that, when combined with an antidepressant, ginkgo biloba can effectively improve symptoms of depression and decrease levels of S100B, a marker of brain injury.

Another 2019 randomized control trial in 40 people with depression after having a stroke found that those who consumed ginkgo biloba with an antidepressant medication experienced significant improvements in depressive symptoms compared to those who only took an antidepressant.

Nonetheless, most studies have been conducted in animals or older adults. Further studies are needed to understand the relationship between ginkgo biloba and depression in the wider population.

Other Uses

In addition to the potential health benefits listed above, some people use  ginkgo biloba to improve the following conditions:

• Tinnitus: There is limited evidence that, when combined with antioxidant therapy, ginkgo biloba may effectively reduce tinnitus symptoms (ringing in the ears). However, no evidence suggests that ginkgo biloba alone affects tinnitus.
• Premenstrual syndrome (PMS): Some older studies suggest that the herb may help reduce the symptoms of premenstrual syndrome. However, further studies are needed.
• Schizophrenia: One 2015 review of eight randomized control trials found that, combined with antipsychotics, ginkgo biloba may improve symptoms of schizophrenia. Additionally, its safety in individuals with chronic schizophrenia has not been well-established.
• Vertigo: A 2021 industry-funded randomized control trial found that 80 mg of ginkgo biloba, taken twice daily for 12 weeks, combined with balance training, led to improvements in age-related vertigo and dizziness.
  

Side Effects of Ginkgo Biloba

Although consuming moderate amounts of ginkgo biloba seems to be safe for most people, there are some potential side effects to be aware of, including:

• Headache
• Upset stomach
• Dizziness
• Palpitations
• Constipation
• Allergic reactions
  

Precautions

Ginkgo biloba may be unsafe during pregnancy, as it may cause early labor or excessive bleeding if used near delivery.

Little is known about its safety in nursing people or children.

There is some evidence that it may increase the likelihood of having seizures. People with epilepsy or those prone to seizures should avoid ginkgo biloba unless otherwise instructed by their healthcare provider.

Ginkgo biloba may increase the risk of bleeding, so individuals with bleeding disorders should use it cautiously.

Dosage: How Much Ginkgo Biloba Should I Take?

There are no official recommendations on how much ginkgo biloba a person should take. However, most studies have used daily doses of 60 to 240 mg, often divided into smaller doses throughout the day without significant side effects.

While there is no established upper limit for ginkgo biloba extract, some research suggests that the maximum recommended daily dose is 240 mg daily.

Long-term or high-dose ginkgo biloba use seems more likely to cause adverse side effects.

Interactions

Ginkgo biloba supplements may interact with certain medications, including:

• Medications to treat certain mental health conditions: Monoamine oxidase inhibitors (MAOIs), Xanax (alprazolam), and Haldol (haloperidol).
• Blood thinners and other supplements that may increase bleeding: Jantoven (warfarin), aspirin, garlic, ginger
• Certain blood pressure medications: Procardia (nifedipine), a calcium channel blocker used to treat high blood pressure and irregular heartbeats.

Consult with a healthcare provider before using ginkgo biloba, especially if taking other herbal supplements or prescription medications.

How to Store Ginkgo Biloba

Store ginkgo biloba supplements in a dry, cool place away from moisture and direct sunlight and out of the sight and reach of children and pets. When stored properly, most supplements will last up to two years.

However, there are many formulations and manufacturers of ginkgo biloba supplements, so always follow storage instructions as provided on the supplement label.

Supplements can lose potency as they age, so most manufacturers recommend discarding them after expiration.

Sources & What to Look For

Ginkgo biloba supplements can be purchased from local retail stores and health supplement stores. They are available in the form of:

• Capsules
• Powder/dried leaves used to make tea
• Tablets
• Liquid extracts

Look for supplements that contain ginkgo biloba in a form called EGb 761, which is standardized to contain 24% flavonol glycosides and 6% terpenoids. This form has been used in most clinical trials showing positive health benefits.

When choosing a supplement, it is also a good idea to purchase from a reputable supplier that utilizes third-party testing, such as from USP or ConsumerLab.com, to ensure what is in the supplement matches the product label.

Similar Supplements

Other herbal supplements with similar, health-promoting properties include:

• Carnosine
• Curcumin
• Lycopene

Carnosine is a dipeptide naturally produced by the human body. It is made from the amino acids alanine and histidine. Although research is limited, preliminary studies suggest that carnosine may be protective against cognitive decline, both in older adults and individuals with mild cognitive impairment.

Curcumin, a substance in turmeric, has powerful anti-inflammatory properties and may help improve memory and attention in older adults without dementia.

Lycopene, a potent antioxidant found in red and pink fruits and vegetables, can support heart and cognitive health. It may also improve sleep quality and reduce the risk of certain cancers, such as prostate cancer.

Summary

Ginkgo biloba is an herb with anti-inflammatory, antioxidant properties traditionally used in Chinese medicine. It may also help improve circulation and blood flow. Because of these properties, some evidence suggests that the herb may offer health benefits such as improving symptoms of dementia and supporting eye health. However, more research is needed to understand its safety and effectiveness fully.

If you're considering taking ginkgo biloba supplements, talk with your healthcare provider to discuss how they may benefit or affect your health.