Life Extension Magazine®

What is Bilberry?

Studies show that bilberry may protect against eye disorders like glaucoma and cataracts, as well as cardiovascular issues and type II diabetes.

Scientifically reviewed by: Amanda Martin, DC, in June 2024. Written by: Laurie Mathena.

Bilberries (Vaccinium myrtillus) are deep blue berries that resemble blueberries.

Although small-in-size, they are densely packed with health-promoting compounds like anthocyanins, flavanols, and more.

Bilberries have been used historically as a tea to treat conditions ranging from diarrhea to inflammation of the throat.1

In more recent years, they have gained attention for their ability to protect against eye diseases like glaucoma, while helping to manage blood sugar, reduce cholesterol, support metabolic health and more.

Potent Eye Protection

As of 2017, over 7 million Americans had vision loss or blindness, out of which 1.6 million were younger than 40.2

The Centers for Disease Control and Prevention predicts that, due to aging and chronic diseases like type II diabetes, by 2050 this number may reach almost nine million.3

Bilberry extracts offer protection for many of these increasingly common eye conditions.

Studies indicate that bilberry extracts, (alone or in combination with other nutrients that support eye health), help protect vision against disorders like cataract4 and glaucoma,5,6 improve parameters of dry eye syndrome,7 and help improve symptoms related to eye fatigue.8

A clinical study showed that a combination of a specific bilberry extract and French Maritime Pine Bark extract effectively reduced intraocular pressure (pressure inside the eye), which is an underlying factor in glaucoma.6 Glaucoma is a leading cause of blindness. It often occurs because of high pressure in the eye can cause irreversible damage to the optic nerve.9

In one study of people with high intraocular pressure (that had not yet progressed to glaucoma), participants were divided into three groups.

  • The first group received pine bark-bilberry extract (40 mg French maritime pine bark + 80 mg standardized bilberry extract)
  • The second group received standard medical treatment with prescription latanoprost eye drops.
  • The third group received both pine bark-bilberry supplement and prescription latanoprost eye drops.

Reduction in intraocular pressure was demonstrated in all three groups. Participants taking the pine bark-bilberry formulation, beginning at six weeks, and continuing through to 24 weeks, had significantly reduced eye pressure. By the sixteenth week, the combination extract had reduced intraocular pressure readings by a meaningful 24% — comparable to the drug, but with a better safety profile. Subjects using the prescription eye drops lowered their eye pressure by an average of 28%, beginning from the fourth treatment week.

But by far, the most compelling results were seen in the group that used the combination of pine bark-bilberry formulation and the latanoprost drops. A significant, average reduction in intraocular pressure of 28% began at four weeks—but when the study ended at 24 weeks, the decrease in eye pressure had reached approximately 40%!

This means that the pine bark-bilberry compound appeared to have an additive effect with the latanoprost drops to amplify the reduction of intraocular pressure better than either agent alone. Study participants also experienced improved blood flow, including to the retina.6

Bilberries may contribute to eye health and visual function by many possible mechanisms, for example, by antioxidant activity, stabilization of collagen, anti-inflammatory action, increased blood flow to the vessels of the eyes, and enhanced resynthesis of rhodopsin,10 a protein necessary for night vision.11

Bilberry Regulates Metabolic Health

Scientists believe that increasing the intake of fruits like bilberry may help improve the long-term prospects for cardiovascular disease, type II diabetes, and obesity.12

Bilberries are one of the richest sources of anthocyanins, which are under investigation for a role in the prevention of metabolic disease and cardiovascular disease.

In a human cell study, bilberry extracts inhibit an angiotensin-converting enzyme, better known as ACE.13 This enzyme contributes to hypertension by promoting constriction of the arteries.14

In a study of participants with metabolic syndrome, consuming 400 grams of fresh bilberries daily for eight weeks resulted in a reduction in C-reactive protein and other inflammatory markers.15

A review of four randomized controlled clinical trials conducted in China examined the effect of supplementation with a combination extract of bilberry and black currant and found that it lowered average levels of HbA1c (a measure of blood sugar levels) over a three-month period.

This effect was especially notable in older individuals, those with type II diabetes, and those participating in longer-term trials. In subjects with high cholesterol, type II diabetes, or metabolic syndrome, the bilberry and black currant extract significantly reduced total and LDL cholesterol after four weeks.16

Compounds in Bilberry

Bilberries contain a wide array of phenolic compounds with proven health benefits. The most notable include the following:

  • Anthocyanins. These are the plant compounds that give bilberries their deep blue color, found in both pulp and peel. The anthocyanins in bilberries positively influence the body's antioxidant response and support metabolic and cardiovascular health.12
  • Flavonoids. Flavonoids are reported to have anti-inflammatory activity.10 In a large cohort study, higher intake of flavonoids and anthocyanins was associated with decreased insulin resistance in women.17 Flavonoids found in bilberries have beneficial effects on microcirculation.10
  • Tannins. Plants in the bilberry family are one of the richest sources of tannins, a group of polyphenolic compounds that may have potential to manage or even delay the onset of type II diabetes.10  


Bilberries hold numerous benefits for those seeking to optimize their health and well-being.

This tiny fruit is packed with some of nature's most potent health-promoting substances, such as anthocyanins, flavonoids (including quercetin), and tannins.  

Scientific studies confirm that bilberry could offer targeted protection for eye health, while helping protect against conditions like cardiovascular disease and type II diabetes.

Bilberry appears to be safe and has no known drug interactions. A suggested supplemental dose is one 100 mg capsule daily of bilberry extract standardized to contain 25% anthocyanins.

If you have any questions on the scientific content of this article, please call a Life Extension Wellness Specialist at 1-866-864-3027.


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  3. Available at: Accessed March 8, 2024.
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  8. Ozawa Y, Kawashima M, Inoue S, et al. Bilberry extract supplementation for preventing eye fatigue in video display terminal workers. J Nutr Health Aging. 2015 May;19(5):548-54.
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  12. Chan SW, Tomlinson B. Effects of Bilberry Supplementation on Metabolic and Cardiovascular Disease Risk. Molecules. 2020Apr 3;25(7).
  13. Persson IA, Persson K, Andersson RG. Effect of Vaccinium myrtillus and its polyphenols on angiotensin-converting enzyme activity in human endothelial cells. J Agric Food Chem. 2009 Jun 10;57(11):4626-9.
  14. Wong MKS. Angiotensin Converting Enzymes. Handbook of Hormones. 2016:4.
  15. Kolehmainen M, Mykkänen O, Kirjavainen PV, et al. Bilberries reduce low-grade inflammation in individuals with features of metabolic syndrome. Mol Nutr Food Res. 2012 Oct;56(10):1501-10.
  16. Grohmann T, Litts C, Horgan G, et al. Efficacy of Bilberry and Grape Seed Extract Supplement Interventions to Improve Glucose and Cholesterol Metabolism and Blood Pressure in Different Populations-A Systematic Review of the Literature. Nutrients. 2021 May 17;13(5).
  17. Jennings A, Welch AA, Spector T, et al. Intakes of anthocyanins and flavones are associated with biomarkers of insulin resistance and inflammation in women. J Nutr. 2014 Feb;144(2):202-8.