Blue Berry Eyebright: Claims without Evidence
I tried Blue Berry Eyebright and improved my eyesight!”
The rest of the ad is a testimonial from “Earle” who suffers from macular degeneration. Reading the ad, it’s clear Blue Berry Eyebright is a supplement specifically at people worried about their vision, and macular degeneration.
What is Macular Degeneration?
I’ve blogged in detail about age-related macular degeneration (AMD) before. The macula is a small area in the center of the retina of the eye that provides us with the highest resolution of vision, making activities like driving and reading possible. In some, the macula degenerate. Complete vision loss is infrequent: You can lose the central vision, but peripheral vision is usually maintained. AMD is the leading cause of adult blindness and severe visual impairment in industrialized countries. Despite its prevalence, little is known about the cause. Age is the single biggest risk factor. Other factors that may be important include smoking history, female gender, Caucasian race, high blood pressure, obesity, and diet. There are few treatment options for AMD, and no known cure.
There is scientific evidence to show that antioxidants plus zinc modestly slow the progression of AMD in those that already with the disease. They don’t reverse it, however. And importantly, patients with no AMD, or early AMD, don’t seem to benefit from supplements. . Lutein is another supplement that has been studied for the prevention of AMD – but the evidence for lutein supplements is not strong. The current advice for those without AMD is to ensure lutein is a part of your regular diet. But if you don’t have AMD, there’s no evidence to suggest you should take any special supplements. So let’s take a science-based look at Blue Berry Eyebright.
The ad for Blue Berry Eyebright makes the following statement about AMD:
AMD can be helped! Today we know from scientific studies, that flavonoid rich extracts of berries and of Marigold (Lutein) offer significant benefits in the prevention and even treatment of AMD.
This is bold statement, give the actual scientific evidence on AMD. But the ad goes further…it implies your vision can actually improve:
“In June 2006 my eyesight on the right eye was 20/30+. In April 2007, my vision had slipped to 20/60+, a dramatic deterioration. Shortly after I started taking the prescribed dosage of Blue Berry Eyebright, on a daily basis (and I am still taking it). When I met for my eye exam, my vision in my right eye had improve to 20/25+, which was much better..”
What’s being described here is a test of visual acuity, and implies Blue Berry Eyebright can actually improve your vision, reversing AMD.
Here are the ingredients, as per the Canadian website:
Blueberry Fruit Extract 400 mg, 5:1 equal to 2000 mg dry berries: “Known from Second World War when the fighter pilots were eating blueberries before their raids to better their night sight. Blueberries are rich in flavonoids, which are good for the small blood vessels and will decrease the build up of toxins. Phyto-ingredients from blueberries are also said to have a beneficial influence on the enzymatic processes in the eye.”
The Science: The science of vision has progressed since the Second World War. There’s no published evidence that blueberries have any meaningful effects on vision. Blueberry fruit has fibre, and vitamin C. It also contains chemical compounds such as ellagitannins, flavonols (quercetin and kaempferol), catechins, phenolic acids,and resveratrol. There’s also some beta-carotene, chlorogenic acid, glutathione, and alpha-tocopherol (vitamin E. There are over 25 individual anthocyanidins (antioxidants), in blueberries, but whether they’re absorbed is questionable. There is no information available to show that any of these compounds are in the “extract” formula this product uses.
Eyebright Parts Extract 200 mg, 5:1 equal to 1000 mg dry herb: “According to old folk medicine the plant eyebright was good for the mucous membranes of the eye. Many elderly people have problems with dry eyes and eyebright can help to get a better balance in the mucous membranes and avoid irritation of the eyes.”
The Science: We need more than “old folk medicine” to support a scientific claim. There’s no published evidence that eyebright, a herb, (Euphrasia rostkoviana) has any of these effects. When used orally or directly in the eye, eyebright has been associated with adverse effects that include headache, increased eye pressure, itching, swelling of eyelid margins, dim vision, photophobia and more. However, it is approved as a food flavouring product in Europe.
Grape Seed Extract 40 mg, 25:1 equal to 1000 mg dry seeds: “Strong flavonoids that just like blueberries will decrease the build up of toxins from the cells. They are also a strong anti-oxidant, which will counteract the damaging effects of free radicals – especially in watery environments like the eye.”
The Science: There’s no published evidence to demonstrate that grape seeds (Vitis vinifera) have any of these effects. “Decrease the build up of toxins” is a meaningless phrase. Grape seeds contain the antioxidants proanthocyanidins, but there’s no published information to suggest they have any meaningful effects on vision.
Marigold Parts Extract 50 mg, (10 mg Lutein): “Found in marigold flowers, spinach and other green leafy vegetables. According to clinical studies you should take at least 6 mg of Lutein per day. This is done most easily by taking a supplement.”
The Science: There’s no published evidence that marigold has any therapeutic effects for vision. Lutein supplements under 10mg/day are generally considered safe. There’s some evidence that lutein can improve some symptoms of established macular degeration, but it doesn’t seem to affect the progression of of the disease. While there is some data that suggest that people with diets high in lutien are at lower risk of AMD, it is not clear that lutein supplements provide the same benefit.
I looked further at New Nordic’s own “research” on the product. None of the citations provide evidence that the product offers any meaningful benefits. One of the citations is incomplete, and a few look completely irrelevant.
What does Health Canada say?
Blue Berry Eyebright is approved by Health Canada’s Natural Health Products Directorate (search product 80016466 here) with the approved Recommended Use:
Used in Herbal Medicine to help slow the progression of disorders of the eye, such as diabetic and hypertensive retinopathy and macular degeneration.
Given there’s no published evidence to demonstrate that the ingredients, either alone or in combination, have any effectiveness against these conditions, the Recommended Use is not an science-based statement. Another disappointment from the Natural Health Products Directorate, which continues to illustrate that “safe and effective” is a largely meaningless term.
Curiously, Health Canada’s approval data gives a different ingredient list than the manufacturer’s own website. According to Health Canada, Blue Berry Eyebright only contains Vaccinium myrtillus (bilberry). Unfortunately, there’s no credible evidence to demonstrate that bilberry has any effect on macular degeneration.
The best approach to preventing AMD, in the absence of disease, is to quit smoking, eat a healthy diet rich in sources of lutein (green leafy vegetables), and get your eyes checked regularly. If you have AMD, antioxidant vitamins may be appropriate – ask your physician. Despite Health Canada’s endorsement, there’s no persuasive evidence that Blue Berry Eyebright will have any meaningful effects on preventing or treating macular degeneration, or improving your vision overall. Blue Berry Eyebright has no place in the science-based pharmacy.
Natural Medicines Comprehensive Database [Internet]. Stockton (CA):Therapeutic Research Faculty; c1995-2010 [cited 2010 September 11]. (Subscription required to view.)
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Tags: blue berry eyebright, eyebright, grape seed, macular degeneration, marigold, new nordic, review