- Health benefits of bilberry
- Nutrition facts
- Side effects of bilberry
- Where to buy
Are blueberries and bilberries the same thing?
No. The bilberry (Vaccinium myrtillus) is a close relative of the blueberry (Vaccinium cyanococcus). Both are of the same plant genus and produce fruit which look and taste similar. The main difference is that bilberries come from Europe, while blueberries are native to North America.
To the novice, they look almost the same on the outside.
Bilberries have a slightly darker skin and they don’t grow in clusters on the bush. On average, they’re smaller than blueberries.
Both of these traits make them harder to harvest.
The inside of their flesh is a reddish purple, unlike blueberries whose pulp is white with a hint of green.
How to tell the difference between a bilberry and a blueberry is that the latter has what looks like a crown on the end. With bilberries, their crown is less pronounced, as they tend to be smooth all around. If in doubt, break one open to see the color inside; blueberries will always be whitish.
The European berry produces a more intense flavor and juicier flesh than the American. They’re more fragile and are notorious for staining what’s around them. That’s why you never see imported fresh bilberries for sale in the US or Canada. However on Amazon, you can order them frozen.
While both contain high amounts of anthocyanins, which are a broad class of pigments with potent antioxidant activity, the concentrations found in each differ. For this reason, the nutritional and medical benefits of each are not directly interchangeable.
Here are the reasons you may want to choose the one from across the pond…
Health benefits of bilberry
1. More antioxidants than blueberries
When you compare the ORAC values of wild bilberries vs. blueberries, they are 7,570 and 4,669, respectively. This means that bilberry has around 60% higher antioxidant activity when comparing equal weights of each.
Even though the conventionally cultivated blueberries you get the grocery store have lower antioxidant activity overall, wild blueberries actually test higher than the average for bilberries, coming in with an ORAC value of 9,621 vs. 7,570 (about 25% higher).
Cyanidin is most prevalent type of antioxidant found in bilberries. Delphinidin and petunidin are next, but at concentrations that are about 2.5 fold lower than cyandin.
Blueberries are similar, with cyanidin being the most concentrated, followed by delphinidin, malvidin, and then petunidin. (1) (2)
2. Better night vision
The belief that bilberries are good for eyes dates back to WWII. Stories were circulated that pilots in the UK’s Royal Air Force (RAF) supplemented with them to improve their night vision. Whether this is true or not is disputed.
The evidence suggests that these berries, along with carrots, were used as part of a propaganda campaign by the Allies to explain why suddenly, Nazi planes were being shot out of the sky with pinpoint accuracy at night.
It wasn’t improved night vision of the pilots, but rather the invention of radar which was responsible for this advantage. To keep it secret, false stories about superfoods for eyesight were disseminated by the military. (3)
Nonetheless, the hype did lead to legitimate research on the topic after the war. Based on studies done during the 1960’s it was reported that:
“The extracts, when administered alone or in association with beta-carotene and vitamin E to healthy patients, induced a significant improvement in night vision, a quicker adaption to darkness, and a faster restoration of visual acuity following exposure to a flash light.”
Today, the brand Mirtoselect bilberry extract and pycnogenol are being studied for these purported benefits. (4) (5)
3. Adjunctive supplement for macular degeneration
The Age-Related Eye Disease Study (AREDS) was a major series of clinical trials sponsored by the National Institutes of Health (NIH). These are the only nutritional studies large and extensive enough to conclude with reasonable certainty that certain antioxidants and minerals may reduce the risk of getting age-related macular degeneration (AMD).
Specifically, it was beta-carotene, lutein, zeaxanthin, and zinc found to be helpful. (6)
Other antioxidants, such as the anthocyanins and polyphenols found in bilberries, have limited research on them when it comes to eye disease.
That said, there is preliminary evidence that’s encouraging and “they pose a viable complement in the venue of treating ocular disease and conditions.” (7)
In 2005, Russian scientists published the results of a study using OXYS rats. Those are an inbred strain of rats that have been used since the 1970’s in eye health research. Due to their genetics, they are prone to develop age-related vision problems.
For the group of rats whose diet consisted of 25% bilberry extract, it “completely prevented impairments in the lenses and retina.” Compare that to the control group, of whom 70% had macular degeneration and cataracts after 3 months. (8)
Studies using rabbits and mice have also reported that the berry extract reduces pro-inflammatory cytokines in the eyes and decreases retinal cell damage. (9) (10)
4. Eye floaters
Some have proposed bilberry for eye floaters. While not studied and a different condition than AMD and cataracts, most floaters are the result of age-related changes in the vitreous (a jelly-like substance) inside the eyeball. In theory, anything to reduce damage to this tissue and slow its aging might help in preventing eye floaters.
Given the evidence that extracts of bilberry help reduce certain types of inflammation and damage in the eye, it’s reasonable to theorize the plant could be useful for this condition. However, it has not been clinical studied.
5. May reduce LED blue light eye damage
Many LED manufacturers use blue LED diodes as the primary and then “down convert” their appearance to white light using phosphor. This means that the LEDs that backlight your cell phone, tablet, and monitor are probably exposing you to high amounts of blue wavelengths… even though you don’t really notice it.
While still debated, the body of evidence that this blue LED light is bad for you keeps piling up.
Even the American Medical Association (AMA) put out an official warning for municipalities in 2016 to use caution when switching over their street lights to energy efficient LED bulbs because:
“Discomfort and disability from intense, blue-rich LED lighting can decrease visual acuity and safety…”
…and they suppress your natural melatonin production at night, which can contribute to difficulty falling asleep and insomnia. (11)
In a study where cultured eye cells were exposed to blue LED light, scientists at a Japanese university report that bilberry extract appears to help protect against the damage from them:
The reduction in caspase-3/7 activation wasn’t as good as lingonberry, but it was nearly a third better than the untreated cells. They said this may also benefit macular degeneration and red cone dystrophy (retinitis pigmentosa). (12)
6. Lowering eye pressure may slow glaucoma
Glaucoma is the leading cause of blindness among those of black or Hispanic origin. Between the ages of 45 and 65, if you’re black you are 15x more likely than whites to experience blindness from this eye disease. While other ethnicities are lower risk, glaucoma is relatively common eye disease regardless. (13)
While dependable preventive measures are not yet known, in general the research has concluded that lowering the intraocular pressure (IOP) in the eyeball slows progression. This is because it takes pressure off the optic nerve, and hence, slows the damage/deterioration.
A rigorous stand-alone bilberry glaucoma study has not yet been done, but there has been with the Mirtogenol supplement. That’s a branded bilberry extract (Mirtoselect) combined with a French maritime pine bark extract (Pycnogenol).
With the bilberry and pine bark extract supplement, intraocular pressure was lowered in 19 out of 20 patients taking it. In the control group of 18 patients, only one experienced this benefit. These results suggest the berry may be good for glaucoma, by lowering IOP.
The catch is that none of these patients had glaucoma, but they did have ocular hypertension which is the early warning sign for the disease.
This and other studies involving Mitrogenol have reported exciting results for IOP improvement, with the most recent being published in 2017.
However, there are not FDA clinical trials to prove this benefit and therefore, it’s intended use is as a dietary supplement only and not for the diagnosis, treatment, cure, or prevention of any disease. (14) (15) (16)
Mitrogenol is made and distributed by the Swiss company Horphag Research and the Italian company Indena. In the US, Canada, and UK, Mirtogenol extract is sold through the brand Life Extension as their Eye Pressure Support supplement which is available on Amazon.
7. Dry eyes relief
Is bilberry good for dry eyes?
In 2017, the results of a randomized and double-blinded clinical trial were published which pitted Mirtoselect bilberry extract against placebo. 22 people with dry eyes who were otherwise healthy participated.
For the 11 patients who took the berry extract, they experienced a significant improvement according to Schirmer’s test, which is a widely used metric for measuring tear production and eye moisture. The 10 people taking placebo didn’t experience any significant change.
Plasma biological antioxidant potential (BAP) was also measured. In the bilberry group, the BAP measurement increased after 4 weeks in a statistically significant manner. This was not seen in the placebo group. The results suggest that oxidative damage was probably lower in the group using the Mirtoselect berry extract. (17)
8. Weight loss
As published in the European Journal of Clinical Nutrition, a Finnish university conducted a clinical trial involving 110 obese women. In a randomized order, each were placed on 1 of 4 berry diets for 33-35 days:
- bilberries (BBs)
- sea buckthorn (SB)
- sea buckthorn phenolic extract (SBe)
- sea buckthorn oil (SBo)
After a 30-39 day washout period, each participant repeated the process with another berry diet. They continued this until all 4 diets were tried.
The daily dosage was equivalent to the amount found in 100g (3.5oz). For example, either 100g of fresh bilberries or the amount of sea buckthorn oil derived from 100g of fresh sea buckthorn.
The results of the study found a small but significant decrease in body weight and fat percentage when the 110 women were consuming the berries and their extracts. However, bilberry was the one that was best for waist circumference, suggesting it may be particularly good for belly fat. (18)
While all this may seem unrelated to eye health, type 2 diabetes correlates with obesity. A side effect of that disease, diabetic retinopathy, is the number one cause of blindness among the diabetic population.
9. Diabetic blood sugar control
In 2017, a medical university in Bulgaria found that extracts of bilberry fruit inhibit the activity of enzymes in our digestive tract that are used to breakdown carbs.
By reducing the effect of a-glucosidase enzymes, carbs (sugars) are digested slower. Some type 2 diabetic medicines work through this same mechanism. (19)
The nutrition facts for fresh bilberries are comparable to wild blueberries, which are 80 calories per serving of 1 cup (140g). With that there’s 6g of fiber, low sugar content of around 7g, some essential minerals like manganese and zinc, and moderate amounts of vitamins C and E.
Freeze-dried bilberry powder has the water removed so the calorie count will be higher by weight. It still offers the same ratios of macronutrients. The antioxidants cyanidin, delphinidin and petunidin are well preserved and highly concentrated.
Whether you eat fresh, freeze-dried, or frozen bilberry, all forms are nutrient dense and can be part of low calorie and low glycemic diets. (20)
Side effects of bilberry
As with their relative the blueberry, bilberry is a well tolerated food. It is of very low allergy risk and is not known for causing digestive problems like abdominal pain, diarrhea, constipation, or gas and bloating. The most likely adverse reaction from eating fresh bilberry or taking bilberry supplements is lower blood pressure and/or lower blood sugar.
While normally those would be considered benefits, in some people they could be dangerous. Particularly for those who are on medications to carefully control those parameters, as the bilberry may be a contraindication due to drug interactions with blood pressure and diabetic treatments.
Whether it is safe to take bilberry during pregnancy is unknown. While there is no evidence to suggest it’s dangerous, the fact is that bilberry supplements or even the fresh berries as a food have not been studied in pregnant women or those who are breastfeeding. Nor have animal studies taken place.
Where to buy
Even though it’s an indigenous fruit to the United Kingdom, it’s easier there to buy fresh blueberries versus bilberries. This is because their berries are often imported from Chile and other regions which don’t grow the Vaccinium myrtillus species commercially.
With the exception of Finland, Denmark, Norway, Sweden, Poland and other countries in Northern Europe and the North Atlantic, finding where to buy bilberries is nearly impossible. Because of how perishable they are, the importing and exporting of blueberries is the de facto alternative.
In the US and Canada, no major grocery store chains sell fresh or frozen bilberry. You may find jarred preserves and jam, but that’s about it.
In the countries that do sell them fresh, it’s unusual to see certified organic bilberries. This is because many crops are wild harvest and don’t use pesticides, irradiation, or fumigation regardless.
The best substitute for bilberries in recipes will be wild blueberries. You can buy these frozen in bags at Trader Joe’s, Whole Foods, and Sprouts. While not identical, they are higher in antioxidants than conventionally grown blueberries and have a phenolic profile that’s closer to their European cousin.
If you’re after the health benefits and taste but don’t necessarily need the texture of fresh whole fruit, then the best alternative is to buy bilberry powder. As with acai, you can add it to smoothies, oatmeal, or even stir it up in a glass of water. On Amazon, check out Nordic Nordic powder.
For capsule supplements, a good brand is Solaray bilberry extract. It’s sold in vegetarian/vegan capsules and the powder inside is standardized to 36% anthocyanosides. You can also get it on Amazon.
If you want the bilberry extract and pine bark extract that has been clinically researched, Mirtogenol, you can find it at retailers who carry the brand Life Extension, as it’s used in their Eye Pressure Support supplement. It’s available on Amazon.
These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.