NutriDex

The Supplement Research Compendium
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Bilberry

Vaccinium myrtillus

Anthocyanin-rich berry; eye claims overstated, metabolic effects modest.

Mixed evidence ⏳Longevity✨Joint & Skin

✚ Updated · How we grade evidence

Evidence tier
Mixed
Research weight
Citations
8 verified / 8
Classification
Longevity
❝
What the evidence says. Graded mixed: the marketed night-vision benefit is not supported by rigorous RCTs, and the cardiometabolic meta-analysis was mostly null apart from HbA1c and triglycerides. Most positive signals come from small, short, or industry-linked single trials. (Mixed evidence: Conflicting results across studies; benefit uncertain.)

What is Bilberry?

Bilberry (Vaccinium myrtillus) is a longevity supplement used for antioxidant anthocyanin source. NutriDex grades the human evidence as Mixed. Bilberry is a wild European relative of the blueberry, prized for its dark anthocyanin pigments. Its most famous claim — sharper night vision — fails when tested properly: a systematic review found the four most rigorous RCTs were all negative. Cardiometabolic data are modest: a 2025 meta-analysis of bilberry trials found only a marginal HbA1c drop and a triglyceride effect, with no change in fasting glucose, total cholesterol, HDL, blood pressure or inflammation. A broader berry meta-analysis credited bilberry with small LDL reductions (~0.30 mmol/L) and HDL rises. An open-label post-heart-attack trial reported a 38 m gain in 6-minute walk distance and lower oxidized LDL. Small single trials suggest bilberry/pine-bark combos lower eye pressure and that extract improves tear secretion in dry eye. Overall the berry is a reasonable antioxidant food, but supplement claims outrun the evidence.

Purported Benefits

✓Antioxidant anthocyanin source
✓Small lipid improvements (LDL/HDL)
✓Modest glycaemic support
✓Tear secretion in dry eye (early)

Evidence by outcome

The same supplement can be well-proven for one use and unproven for another — here is the human evidence graded outcome by outcome.

OutcomeEvidenceEffectStudies
Night vision improvementSystematic review found the 4 most rigorous RCTs all negative; the classic night-vision claim is not supported. Moderate — no effect · negligible 1
LDL/HDL cholesterol16-RCT berry meta-analysis: LDL ~-0.30 mmol/L, HDL ~+0.12; small effects, bilberry pooled among berries. Moderate ↑ benefit · small 1
Glycaemic control (HbA1c/fasting glucose)2025 bilberry meta-analysis showed only marginal HbA1c drop (p=0.06), glucose unchanged; anthocyanin pooled data more favorable. Mixed ↔ mixed · small 3
TriglyceridesBilberry and broader anthocyanin meta-analyses report a triglyceride-lowering signal; modest and heterogeneous. Preliminary ↑ benefit · small 2
Dry-eye tear secretionSingle small (n=21) double-blind RCT improved Schirmer test; needs replication. Preliminary ↑ benefit 1
Intraocular pressureOne small RCT used a bilberry+pine-bark combo, so the effect is not attributable to bilberry alone. Preliminary ↑ benefit · small 1

Dosing & Compounds

Typical Dose
Standardized extract (e.g. Mirtoselect, ~36% anthocyanins) 80–160 mg/day, or freeze-dried fruit/powder; no single validated dose.
Active Compounds
Anthocyanins (delphinidin & cyanidin glycosides)Pterostilbene / resveratrolTannins

Safety & Cautions

Bilberry fruit is well tolerated as a food; concentrated extracts are generally safe short-term but lack long-term safety data. Because anthocyanins can mildly lower blood glucose and inhibit platelet aggregation, use caution combining high-dose extracts with antidiabetic drugs (additive hypoglycaemia) or anticoagulants/antiplatelets such as warfarin, aspirin or clopidogrel (theoretical bleeding risk). Stop extracts about two weeks before surgery, and prefer food sources in pregnancy or breastfeeding where safety is unstudied. Educational only — always check with your doctor or pharmacist before combining Bilberry with any medicine.

Key Studies

Meta-analysis Talebi 2025 ✓ PubMed
Meta-analysis of 8 bilberry RCTs (n=409): only marginal HbA1c drop (-1.63%, p=0.06) and a triglyceride effect; glucose, lipids, BP, CRP unchanged.
Meta-analysis Mao 2023 ✓ PubMed
Anthocyanin meta-analysis in T2D (13 RCTs, n=703): HbA1c -0.31%, fasting glucose -0.63 mmol/L, TG -0.45 mmol/L, LDL -0.26 mmol/L.
Meta-analysis Zhu 2015 ✓ PubMed
Meta-analysis of 16 RCTs: bilberry lowered LDL ~0.30 mmol/L and raised HDL ~0.12 mmol/L (both p<0.001).
Systematic review Canter & Ernst 2004 ✓ PubMed
Systematic review: the 4 most rigorous RCTs of bilberry anthocyanosides for night vision were all negative; claim not supported.
RCT Arevstrom 2019 ✓ PubMed
Open-label RCT after heart attack (n=50): 40 g/day freeze-dried bilberry improved 6-min walk distance by 38 m and lowered oxidized LDL.
RCT Riva 2017 ✓ PubMed
Randomized double-blind trial (n=21): standardized bilberry extract significantly improved Schirmer tear-secretion test in dry eye (p=0.019).
RCT Hoggard 2013 ✓ Full text
Crossover trial (n=8): a single standardized bilberry extract dose cut postprandial glucose iAUC by 18% vs placebo (p=0.003) in diet-controlled T2D.
RCT Steigerwalt 2008 ✓ PubMed
RCT (n=38): bilberry+pine-bark (Mirtogenol) lowered intraocular pressure from ~25 to 22 mmHg over 3 months vs no change in controls.
8 sources cited · 8 verified Search all studies on PubMed ↗

Common questions about Bilberry

What is Bilberry used for?

Bilberry is most often taken for Antioxidant anthocyanin source, Small lipid improvements (LDL/HDL), Modest glycaemic support, Tear secretion in dry eye (early). Anthocyanin-rich berry; eye claims overstated, metabolic effects modest.

Does Bilberry work — what does the evidence say?

Mixed evidence. Conflicting results across studies; benefit uncertain. Bilberry is a wild European relative of the blueberry, prized for its dark anthocyanin pigments. Its most famous claim — sharper night vision — fails when tested properly: a systematic review found the four most rigorous RCTs were all negative. Cardiometabolic data are modest: a 2025 meta-analysis of bilberry trials found only a marginal HbA1c drop and a triglyceride effect, with no change in fasting glucose, total cholesterol, HDL, blood pressure or inflammation. A broader berry meta-analysis credited bilberry with small LDL reductions (~0.30 mmol/L) and HDL rises. An open-label post-heart-attack trial reported a 38 m gain in 6-minute walk distance and lower oxidized LDL. Small single trials suggest bilberry/pine-bark combos lower eye pressure and that extract improves tear secretion in dry eye. Overall the berry is a reasonable antioxidant food, but supplement claims outrun the evidence.

What is the typical dose of Bilberry?

Standardized extract (e.g. Mirtoselect, ~36% anthocyanins) 80–160 mg/day, or freeze-dried fruit/powder; no single validated dose.

Is Bilberry safe? Any cautions or side effects?

Bilberry fruit is well tolerated as a food; concentrated extracts are generally safe short-term but lack long-term safety data. Because anthocyanins can mildly lower blood glucose and inhibit platelet aggregation, use caution combining high-dose extracts with antidiabetic drugs (additive hypoglycaemia) or anticoagulants/antiplatelets such as warfarin, aspirin or clopidogrel (theoretical bleeding risk). Stop extracts about two weeks before surgery, and prefer food sources in pregnancy or breastfeeding where safety is unstudied.

How many studies support Bilberry?

NutriDex cites 8 sources for Bilberry, graded "Mixed".

Cite this page
APA

Peh, D. (2026). Bilberry (Vaccinium myrtillus): Benefits, Dosage, Side Effects & Evidence. NutriDex — The Supplement Research Compendium. Retrieved 26 Jun 2026, from https://nutridex.info/s/bilberry

BibTeX
@misc{nutridex_bilberry,
  author       = {Peh, Daryl},
  title        = {Bilberry (Vaccinium myrtillus): Benefits, Dosage, Side Effects \& Evidence},
  year         = {2026},
  howpublished = {NutriDex --- The Supplement Research Compendium},
  url          = {https://nutridex.info/s/bilberry},
  note         = {Reviewed by Dr Daryl Peh, MBBS Singapore, MMed FM. Accessed 2026-06-26}
}

For medical claims, citing the underlying primary studies linked above is preferred. NutriDex is an educational reference, not medical advice.

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