Bilberry compounds and health effects reviewed
What it found
Bilberry fruits are rich in anthocyanins and other phenolic compounds, and studies in people, animals and cells have linked them to antioxidant, anti-inflammatory, heart, blood sugar, eye and antibacterial effects.
Many of these findings come from lab tests or animals, and the authors say more human research is needed.
What they found
Studies in people
Eye effects
In people with dry eye symptoms, a standardized bilberry extract improved tear secretion. Other studies described beneficial ocular effects of bilberry extracts, including night vision improvement and prevention of cataract and glaucoma.
Animal and lab studies
Antioxidant effects
In rats, bilberry fruits showed antioxidant activity and significantly decreased lipid peroxidation (MDA) and protein oxidation (AOPP) levels compared with controls. In lab tests, bilberry extracts acted as good electron donors and quenched free radicals.
Antimicrobial effects
Bilberry juice inhibited the growth of Neisseria meningitidis by 63% at a concentration of 10 mg/mL. In lab tests, a bilberry extract at the highest concentration used (~86 mg/g) totally inhibited the growth of Streptococcus pneumoniae.
Studies in people and animals
Blood sugar and insulin
In young adults, eating bilberry fruits attenuated postprandial glycemic and insulin responses, with the most insulin-lowering effect at 30 minutes after the meal. In lab tests, polyphenol-rich extracts from bilberry fruits inhibited α-glucosidase and amyloglucosidase.
Heart and blood vessels
In people, daily consumption of moderate amounts (100 mg) of bilberry for two months affected platelet function, blood pressure and HDL-cholesterol. In rats, a bilberry extract increased coronary flow and reduced lactate dehydrogenase release during reperfusion, and was effective in preventing arrhythmias.
Inflammation
In cell lines, bilberry showed strong anti-inflammatory activity with high cell viability. In mice, anthocyanin-rich extracts suppressed liver inflammation markers, and in people with metabolic syndrome, bilberry reduced serum C-reactive protein, IL-6, IL-12 and LPS levels.
Other findings
Nutritional content
Fresh bilberry fruits contain around 84% water, 9.7% carbohydrates, 0.6% proteins, 0.4% fats and 3-3.5% fibres, with an estimated energy value of 192 kJ. They also provide vitamins and minerals, including three main macroelements (Ca, P, Mg) and seven microelements (Fe, Ba, Na, Mn, Cu, Sr, Zn).
Anthocyanins and colour
Anthocyanins are the most abundant phenolic group in bilberry and give the fruit its dark blue colour. The profile has fifteen main compounds based on five aglycones (delphinidin, cyanidin, petunidin, peonidin, malvidin) linked to different sugars.
What the authors conclude
- They say bilberry is a widely consumed fruit with interesting nutritional and therapeutic properties, rich in phytochemical compounds that can be used in various industrial sectors.
- They note that anthocyanins are promising natural colourants that could replace artificial additives, but further stability studies are needed to ensure their stability in final products.
- They advise that more research is needed to confirm the relationship between consuming these berries and their bioactive properties, since most scientific research has been done in vitro.
How it was done
The authors wanted to fully describe bilberry fruits and understand the link between eating them and health benefits. They also wanted to find ways to use fruit that is thrown away because of its shape or appearance.
They gathered and described published research on bilberry's nutrients, phenolic compounds, anthocyanins, health effects and industrial uses. They did not run new experiments.
What it can’t tell you
- Many of the health findings come from lab tests or animals, so they cannot show what happens in people.
- The review did not run new studies, so it cannot prove that eating bilberry causes any health effect.
- The authors note that high dose consumption may cause unwanted effects or interactions with medicines, but the review does not give details on how common or severe these are.
Who paid
- Authors work at
- Instituto Politecnico de Braganca, Portugal
The paper
- Title
- Vaccinium myrtillus L. Fruits as a Novel Source of Phenolic Compounds with Health Benefits and Industrial Applications - A Review
- Type
- ReviewThe authors read earlier studies and describe what they found. It isn’t a new study.
- Evidence
- Studies in people · animals · lab
- Summarised from
- Full text
- Cite
- Pires TCSP, Caleja C, Santos-Buelga C, Barros L, Ferreira ICFR (2020). Vaccinium myrtillus L. Fruits as a Novel Source of Phenolic Compounds with Health Benefits and Industrial Applications - A Review. Current pharmaceutical design. doi:10.2174/1381612826666200317132507Free full textPubMed 32183662DOI
Summary written 29 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error