Bilberry is a small edible fruit better known by the European blueberry or whortleberry and is sometimes mistaken as a huckleberry. (1) Bilberry contains anthocyanins. These polyphenolic compounds provide antioxidants and are responsible for the dark blue and black color of the fruit. (2) Bilberry, much like its cousins the blueberry and cranberry, is popular in pastries, teas, and can be eaten whole. Research suggests that the nutrients in the bilberry fruit may provide medicinal support for the immune system, blood glucose levels, cardiovascular health, cognitive function, the healthy development of cells during normal aging, and support during age-related challenges.
What is Bilberry?
Bilberry, known by the botanical name Vaccinium myrtillus, grows across North America, and regions of Europe and Asia. Bilberry is also a close relative to many other species in the Vaccinium genus, such as blueberry (Vaccinium corymbosum) and cranberry (Vaccinium macrocarpon).
There are 400 species of bilberry and 26 of them are native to North America. (3) A common misconception is that bilberry is the same as huckleberry, and that both are same as blueberry, and each of the three species of plant can be used interchangeably. (4) From a culinary perspective this may be true, but botanically it is not. Additionally, all three plants often share the same “common name.” Below is a list of bilberry species and their common names, which can give the impression that all three plants are the same.
- Vaccinium uliginosum - bog blueberry, bog whortleberry, bog huckleberry, northern bilberry, ground hurts
- Vaccinium caespitosum - dwarf bilberry
- Vaccinium deliciosum - cascade bilberry
- Vaccinium membranaceum - mountain bilberry, black mountain huckleberry, black huckleberry, twin-leaved huckleberry
- Vaccinium ovalifolium - oval-leafed blueberry, oval-leaved bilberry, mountain blueberry, high-bush blueberry
Bilberry, Blueberry, and Huckleberry
Bilberry has several defining characteristics. When compared to other berries, bilberries start out dark red prior to turning blue. They grow on low, solitary bushes with only a few fruit per branch. They are harvested from wild bushes and less frequently cultivated. They are also known for staining the hands, teeth, and turning the tongue the color blue or purple. They are also more tart and have a rougher texture when used in cooking. Bilberry is sometimes favored for use in jams or eaten dried.
Blueberry, specifically highbush blueberry Vaccinium corymbosum and lowbush Vaccinium angustifolium, are the most popular commercial varieties of the blueberry plant sold in North America. (5)(6) The plants are cultivated throughout New Jersey, Michigan, North Carolina, and Washington, but can also be found growing in southern states and across lower Canada. Blueberries grow on more upright and taller bushes. More than 100 varieties of blueberry have been cultivated to produce large fruit yields with small or no seeds.
Huckleberries are part of the Gaylusaccia, Solanum,Pyxothamnus, and Cyanococcus species. (7) Identifying the differences between these species can be difficult as they can share similar appearances and taste depending on the species, where it grows, and how it ripens. In North America, “true huckleberry” includes black huckleberry and box huckleberry. Both grow wild in the southern regions of the U.S. and up into Canada. Huckleberries contain larger seeds and have smaller yields per plant, making them less appealing to consumers. Some cultivators have bred huckleberry with bilberry in an attempt to make the fruit more commercially appealing. (8)
As mentioned previously, bilberry has not been widely cultivated by farmers and does not grow well in gardens. Additionally, bilberry does not like to be disturbed, so moving a mature plant from a wild location to a garden is not advised. (9)(10) Growing bilberry requires extra care and preparation. To start a plant in a garden, look for container-raised bilberry seeds that have already begun to root but not mature. Gardeners will need to buy at least two bushes to allow for cross-pollination or the plant will not produce berries. After purchasing the container, keep them outdoors in a cool place until they can be planted in early spring.
To plant, dig a hole 8-inches deep and twice as wide as the container, then remove the bilberry and plant it in the soil, tuck soil around the edges, and water thoroughly. (11) Add mulch to keep the soil cool and moist. Water when the soil dries and avoid fertilizing too much. The plant will produce berries in the fall.
Bilberry prefers cooler weather in plant hardiness zones 3 through 8. It also prefers acidic soil lower than a pH of 6. If soil acidity is too high, plant the shrub in a raised bed and purchase acidic soil. Bilberry can grow without protection from the sun and wind, but it will require extra shade in the evening if planted in warmer regions.
Research shows that most of the potential medicinal benefits of bilberry are linked to the plant compound anthocyanin. (12) The name anthocyanin comes from the Greek words “anthos,” meaning flower, and “kyanose,” meaning blue. Anthocyanins are a flavonoid and an antioxidant. Anthocyanins are known to react with soil acidity. Soil with low pH produce lighter red or pink berries, and higher pH levels result in darker blue and purple berries.
The deep color of bilberry is important to attract animals, insects, and birds for pollination and seed dispersal. But research also shows that the color is linked to the plant’s ability to survive environmental factors, such as ultraviolet light from the sun, varying temperatures, and disease; the darker the color, the more antioxidants it provides. When consumed by humans, the benefits of anthocyanins are thought to extend to the body and may provide support for several bodily systems, including the immune system, the creation of new cells, and the eyes. In some diets, bilberry is categorized as a “functional food,” meaning it provides positive effects on the body beyond basic nutrition. (13)
Maintaining blood flow to the eyes is essential for visual acuity during normal aging. (14) Disruptions to blood flow can lead to the death of cells and diminished eye health. In a study on the effect of bilberry extract on the formation of new blood vessels, researchers found that bilberry extract positively affected the development of new vessels. The results showed that the bilberry extract had an antioxidant effect that helped to mediate the many steps required in the development of new vessels.
Blue light, a wavelength of visible light frequently produced by a computer screen, has been linked to age-related eye disorders. (15) Researchers found that the antioxidants in bilberry provide protective effects against blue light. When applied to cell cultures, bilberry extracts helped to reduce oxidative stress, free radical production, and damage to DNA caused by the blue light. A similar research study also found that bilberry helped to protect the eyes from UV-B damage, which can occur when spending time outdoors and not looking at the sky. (16)
Bilberry extract is also shown to support eye fatigue induced by computer screens. (17) In a study conducted with 281 workers from ages 20 to 40 years of age, researchers found that bilberry did help to reduce some parameters of eye fatigue. How bilberry could be used to help office workers and other heavy computer users has not been established.
Diet, aging, and environmental factors such as pollution have been shown to contribute to the creation of oxidative free radicals in the cardiovascular system. (18) Cardiovascular disease resulting from ischemia, hypertension, cardiomyopathy, atherosclerosis, and diabetes accounts for around 31% of all deaths worldwide. Antioxidants in bilberry and other small, dark-colored berries have also been studied for the potential to regulate the inflammatory response in the immune system, the formation of plaque, the smooth lining that allows for the expansion and contraction of arteries and vessels, and the development of new cardiovascular cells. Numerous studies have linked bilberry to potentially beneficial effects in the cardiovascular system, specifically related to the removal of free radicals and protective effects on heart tissue and muscle. (19)(20)(21)(22)
Studies show that bilberry may help to support motor and cognitive functions during normal aging. The compounds in bilberry, including “anthocyanin, caffeic acid, catechin, quercetin, kaempferol and tannin,” have been shown to help mediate “signaling pathways involved in inflammation, cell survival, neurotransmission and enhancing neuroplasticity.” (23)(24)
Bilberry Dosage, Warning, and Interactions
Bilberry absorption in the body is unique when compared to other flavonoids. All flavonoids have a sugar “core” that the body must remove before absorption. (25) The body can absorb anthocyanins without the intermediary step of removing the sugar core, making absorption possible just a few minutes after consumption; however, only 11% to 22% of anthocyanin enter the bloodstream and the rest is passed as waste. Due to the poor efficiency of absorption, doses of bilberry and plant extracts may need to be larger.
Doses of bilberry supplements can vary by large margins. Products that seeks to address eyestrain contain up to or more than 100mg of bilberry extract. (26) Some supplements also contain similar amounts of the leaf or root extracts. Less research has been conducted on the medicinal effects of the leaf and root parts, and safe dosage amounts have not been established. There have been no reported side effects when taking large doses of bilberry for more than 6 months.
Bilberry may interact with normal blood sugar levels and should be used with caution by people with diabetes. Pregnant women, breastfeeding mothers, and anyone undergoing surgery should consult with a doctor about stopping use or starting use of a bilberry supplement. If changes to health occur immediately stop use and consult a primary care physician.
Bilberry is a versatile plant with many uses. The fruit of bilberry is found in foods, treats, drinks, and supplements. Taking bilberry as a supplement may be ideal as various extraction techniques allow manufacturers to remove and condense the antioxidants into a more bioavailable form for optimal absorption and support in the body.
When shopping for supplements, check out the NHC.com store. We carry a wide variety of brands that are known to follow Good Manufacturing Practices, use third party testing for quality and purity, and contain ingredients made or grown in the USA. Experience bilberry and see if it makes a difference in your life.