Ginkgo biloba supplements: what the evidence says before you buy
We research products from makers' specs and health sources; we do not run hands-on tests. Links to Amazon may earn us a commission at no cost to you. How this works.
- Standardized ginkgo leaf extract, 60 mg. Best for: Adults who want to try ginkgo at a moderate dose. See options on Amazon
- Ginkgo biloba 120 mg extract. Best for: Adults who prefer one capsule a day. See options on Amazon
- Organic ginkgo leaf extract. Best for: Buyers who want certified organic ginkgo. See options on Amazon
What ginkgo biloba is
Ginkgo is an ancient tree often called a living fossil, with a long history in Chinese medicine. The National Center for Complementary and Integrative Health (NCCIH) says ginkgo leaf, usually as an extract, is the most common form today.
It is promoted for memory and cognitive decline, anxiety, heart disease, diabetes, PMS, tinnitus and more, and for boosting thinking in healthy people.
What the research shows
| Claim | What NCCIH reports |
|---|---|
| Preventing dementia | Not shown in three large studies |
| Dementia symptoms | Possible modest benefit, inconsistent |
| Memory in healthy people | Uncertain; much research low quality |
| Heart disease, blood pressure | Not helpful |
| Tinnitus | Not helpful |
One of those studies was the Ginkgo Evaluation of Memory (GEM) study, funded by NCCIH and the National Institute on Aging. More than 3,000 people age 75 or older took ginkgo or a placebo for a median of 6 years, with no difference in rates of dementia or Alzheimer's disease.
NCCIH says a small amount of evidence suggests benefit for anxiety, PMS, schizophrenia and vertigo, and possibly stroke rehabilitation, but the evidence is not conclusive. Overall, ginkgo has not been shown effective for any condition studied.
Safety: bleeding, pregnancy and seeds
- Leaf extract. Likely safe for most adults in moderate amounts, used safely in studies lasting as long as 6 years.
- Side effects. Most common are dizziness, digestive symptoms and headache.
- Bleeding. Ginkgo may increase bleeding risk in people taking anticoagulants such as warfarin, and may interact with other drugs.
- Pregnancy. Ginkgo may be unsafe in pregnancy and might cause early labor or extra bleeding during delivery if used near that time. Little is known about breastfeeding.
- Seeds. Fresh ginkgo seeds are toxic, and serious side effects have occurred with roasted seeds or the crude plant. Supplements should use leaf extract.
NOW Foods' ginkgo labels add cautions for anticonvulsants, antidepressants and drugs that affect bleeding time, liver disease, clotting disorders and planned surgery.
How to read a ginkgo label
Many products use a standardized leaf extract. NOW Foods' extract is labeled 50:1 standardized, with a minimum of 24% ginkgoflavonglycosides and 6% terpene lactones.
- NOW Ginkgo Biloba 60 mg: 60 mg standardized extract plus 200 mg ginkgo leaf powder per capsule, taken 1 to 2 times daily, preferably with food.
- NOW Ginkgo Biloba Double Strength: 120 mg standardized extract plus 250 mg organic eleuthero root per capsule, taken once daily with a meal.
Note that the double strength version adds eleuthero, a different herb, so check every ingredient. Compare the extract mg, not the total capsule weight.
How to choose a ginkgo biloba supplement
- Leaf extract, standardized. Look for the flavone glycoside and terpene lactone percentages on the label.
- Single herb or blend. Decide whether you want ginkgo alone or with other herbs.
- Start with the lower strength. Since benefits are unproven, there is little reason to choose the highest dose.
- Follow label limits. NOW Foods' labels say not to exceed the recommended dosage.
- Talk to your doctor if you take blood thinners, seizure medicine or antidepressants, or have surgery planned.
What to look for when you buy
Standardized ginkgo leaf extract, 60 mg
Best for: Adults who want to try ginkgo at a moderate dose
NOW Foods' version lists a 50:1 leaf extract standardized to 24% ginkgoflavonglycosides and 6% terpene lactones, 1 to 2 capsules daily with food.
Watch out: Not for pregnancy. May increase bleeding risk with blood thinners.
See options on AmazonGinkgo biloba 120 mg extract
Best for: Adults who prefer one capsule a day
Higher-strength capsules give 120 mg of standardized extract in a single daily dose.
Watch out: Some 120 mg products add other herbs, such as eleuthero in NOW Foods' version. Read every ingredient.
See options on AmazonOrganic ginkgo leaf extract
Best for: Buyers who want certified organic ginkgo
Organic leaf extract capsules are widely sold, an option if organic certification matters to you.
Watch out: Check whether the label states standardization percentages; not all organic extracts do.
See options on AmazonQuestions people ask
- Does ginkgo biloba improve memory?
- It is uncertain. NCCIH says research on cognitive performance in healthy people is mostly low quality, and ginkgo did not prevent dementia in large studies.
- Are ginkgo biloba supplements safe?
- Leaf extracts are likely safe for most adults in moderate amounts. Ginkgo may raise bleeding risk with blood thinners and may be unsafe in pregnancy.
- Can you overdose on ginkgo biloba?
- Follow the label and do not exceed the recommended dose. Fresh ginkgo seeds are toxic, and serious effects have occurred with roasted seeds or the crude plant.
- What are the side effects of ginkgo biloba?
- The most common are dizziness, digestive symptoms and headache.
- Does ginkgo help tinnitus?
- NCCIH says research suggests ginkgo is not helpful for relieving tinnitus.
- Does ginkgo help with anxiety?
- NCCIH says a small amount of evidence suggests a benefit for anxiety, but the overall evidence is not conclusive. Talk with a provider about proven treatments.
- Can ginkgo prevent Alzheimer's disease?
- No. In the GEM study, more than 3,000 older adults took ginkgo or placebo for a median of 6 years with no difference in Alzheimer's or other dementia.
Sources
- Ginkgo: Usefulness and Safety (nccih.nih.gov), National Center for Complementary and Integrative Health
- Ginkgo Biloba 60 mg Veg Capsules (www.nowfoods.com/products/supplements/ginkgo-biloba-60-mg-veg-capsules), NOW Foods
- Ginkgo Biloba, Double Strength 120 mg Veg Capsules (www.nowfoods.com/products/supplements/ginkgo-biloba-double-strength-120-mg-veg-capsules), NOW Foods