Nutritionist Sarah Dumont-Gale explores bilberries and eye health. Discover what research suggests about bilberry extract, how it compares with lutein and zeaxanthin, and what to check when choosing a supplement.
🕒 6 min read
Bilberries, the cousins of blueberries, have long been used for vision support. Their dark pigments have attracted interest from researchers looking at eye fatigue, tear production and the role of antioxidants in eye health.
So what are the benefits of bilberry for eyes? Small clinical trials suggest certain extracts may help with some measures of screen-related eye fatigue. Understanding the extract, dose and study design helps put those findings into context.
What are bilberries?
Bilberries are small berries closely related to blueberries, cranberries and huckleberries. They grow on shrubs native to northern Europe, with related populations in northern North America.
Sometimes referred to as wild blueberries, bilberries can look very similar to blueberries from the outside. However, the flesh inside is darker, with a purple or crimson hue associated with its anthocyanin pigments.
Why are bilberries of interest for eye health?
Anthocyanins are members of the flavonoid family. Their antioxidant properties are one reason scientists have investigated bilberries: oxidative stress, an imbalance between free radicals and antioxidant defences, is relevant to research on eye health.
Laboratory findings help explain why an ingredient is worth studying. Human trials are needed to establish what it actually does for vision, at what dose and in which people.
How do bilberries support eye health?
Research has explored bilberry extract in people with tired or dry eyes, particularly those using computer screens. The studies below offer useful clues, but tested particular formulations rather than bilberries as a food.
Eye fatigue and dry eye
Office workers may be interested in an eight-week, placebo-controlled trial that enrolled 88 people. Those taking 480mg of a particular bilberry extract daily showed improvements in some measures of eye fatigue, including eye heaviness and discomfort after screen tasks. Eighty participants completed the trial.2
A separate, four-week placebo-controlled trial involving 22 people with dry-eye symptoms investigated a standardised bilberry extract and reported improved tear secretion. These promising findings need confirmation in larger studies and do not mean all bilberry products will give the same result.3
Screen-related discomfort is also a reason to review breaks, blinking, lighting and your glasses prescription with your optician, rather than focusing solely on a supplement.
Bilberry
Bilberry extract with vitamin B2 to help maintain normal vision.
- 50mg bilberry extract per tablet.
- Providing 12.5mg anthocyanidins per tablet.
- With vitamin B2, which helps protect cells from oxidative stress.
Glaucoma
Glaucoma damages the optic nerve and can cause gradual loss of sight. A retrospective study reviewed the records of 332 people with normal-tension glaucoma, including 132 who took bilberry anthocyanins. Some measures of visual function improved in that group over roughly two years.
This was a review of medical records, with a non-treatment comparison group, rather than a randomised placebo-controlled trial. It cannot establish that bilberry caused the improvement or replaces prescribed glaucoma treatment.4
Diabetic retinopathy and cataracts
Diabetic retinopathy affects blood vessels in the retina, while cataracts cloud the lens. Both featured in early bilberry research, but the evidence is insufficient to establish bilberry as a treatment for either condition.
The same caution applies to night vision. The familiar story of British pilots eating bilberry jam during the Second World War helped popularise the idea, but rigorous studies have not found an improvement in night vision in healthy people.1
Bilberry, lutein and zeaxanthin: what is the difference?
Bilberry provides anthocyanin pigments. Lutein and zeaxanthin are different plant pigments, called carotenoids, found in the retina and lens. You can obtain them from foods such as green leafy vegetables, or choose a formulation that states the amount of each ingredient.
For a closer look at these carotenoids, read our guide to lutein and zeaxanthin. Our eye-health supplements range includes bilberry products and formulations containing lutein, zeaxanthin and complementary nutrients.
Eye-health nutrients and evidence at a glance
| Ingredient | Role or research findings | What to know |
|---|---|---|
| Bilberry extract | Small trials have reported improvements in some measures of screen-related eye fatigue and tear production. | Early findings from specific extracts; they do not establish a treatment for eye disease. |
| Lutein and zeaxanthin | Carotenoids found in the retina and lens; included in the AREDS2 formula studied in AMD. | The evidence relates to a particular combination for selected stages of AMD, not every eye supplement. |
| Vitamin B2 | Helps maintain normal vision. Food sources include milk, eggs, mushrooms and fortified cereals. | A normal nutritional role is different from treating an existing eye condition. |
| Zinc and vitamin A | Both contribute to the maintenance of normal vision. | Compare the complete daily serving and overlapping ingredients if you use several supplements. |
| Vitamins C and E | Antioxidant vitamins included in the AREDS2 combination alongside other nutrients. | Their presence alone does not make a product an AREDS2 formula. |
The bilberry row draws on the trials discussed above. The nutritional roles of vitamin B2, zinc and vitamin A are distinct from the clinical evidence for an AMD formula. Milk, eggs, mushrooms and fortified cereals are useful sources of vitamin B2.6, 7
What does AREDS2 tell us?
The AREDS research found that a specific combination of antioxidant vitamins and minerals can reduce progression to advanced age-related macular degeneration in selected people, particularly those with intermediate AMD or late AMD in one eye. AREDS2 investigated lutein and zeaxanthin as part of that combination.
This does not establish that bilberry, lutein alone or a general multivitamin prevents AMD. Ask your eye-care professional whether an AREDS2 formulation is relevant to your diagnosis and check the complete formula, not just the presence of one ingredient.5
How much bilberry should I take for eye health?
There is no single established bilberry dose for eye health. Studies use different extracts, concentrations and durations, so follow the directions on your chosen product rather than copying a trial dose.
Healthspan's Bilberry directions are two tablets daily with water, together or as a divided dose. Each tablet contains 50mg bilberry extract, equivalent to 5,000mg whole bilberry, providing 12.5mg anthocyanidins and 1.4mg vitamin B2. The two-tablet serving therefore supplies 100mg extract, 25mg anthocyanidins and 2.8mg vitamin B2.
What should I check on a bilberry supplement label?
Look for the amount of actual extract, its stated anthocyanin or anthocyanidin content, and the full daily serving. A whole-fruit equivalent is a different measurement from the extract weight, so a larger headline number does not necessarily mean a stronger product.
Also check added nutrients. For example, vitamin B2 contributes to normal vision; that is a different claim from saying bilberry treats an eye condition. If you take medicines or have a medical condition, ask your pharmacist or doctor about suitability before starting bilberry.1
Choosing support for your eyes
Start with the question you want to answer: are you comparing plant extracts, looking for lutein and zeaxanthin, or following advice about a diagnosed eye condition? That makes it easier to compare products on their ingredients and intended use.
Explore Bilberry for bilberry extract with vitamin B2, Retinex Eye Support for lutein and zeaxanthin with vitamin B2, or compare the wider eye-health range. Supplements fit alongside a varied diet and regular eye checks; persistent symptoms deserve an assessment rather than a change of supplement alone.
