St. John’s wort Revisited
(Continued from Part One)
A newly published study in the journal, Current Eye Research, is raising questions about an herbal remedy commonly used to treat depression.
To find out if St. John’s wort (SJW) use was linked to the debilitating eye condition of cataracts, epidemiologists from the University of Alabama, gathered data on more than 31,000 people age 40 or older.
They found that those who reported cataracts were 59% more likely to also report they had used SJW for at least a year.
This was the first time a correlation had been seen in a human population linking SJW and cataracts confirming the direct cause-and-effect that’s been seen in the lab for more than a decade.
Beginning in 1999, a published study in NewScientist by Dr. Joan Roberts and colleagues from Fordham University, found the active ingredient in SJW, hypericin, can react to visible and ultraviolet light to produce free radicals. The reaction damages proteins in the crystalline lens of the eye, which can lead to a loss of clarity in the lens, the definition of a cataract.
The frightening thing about the findings is that the effects may not be seen for up to a decade, as cataracts can take five to 10 years to form and are symptomless.
Dr. Roberts is a Professor of Chemistry at Fordham University in New York City who has studied the negative effects of UV radiation and visible light (cataracts, ocular melanoma, macular degeneration) and positive effects (circadian rhythm) of visible light on the human eye.
Besides Fordham, she has worked at the National Institute of Environmental Health Sciences (NIEHS).
IB News Editor Jane Akre interviewed Dr. Roberts recently about the findings in the human population which echo her own.
IB: It's interesting you said you are a proponent of natural, complementary medicine, otherwise I, and others who read this article, might put this in a category of the movement against complementary and natural alternatives by the pharmaceutical industry.
"I support complementary medicine and natural alternatives to prescription drugs. However, the herbs and over-the-counter drugs need to be safe as well as effective"
IB: So what if we recognize the side effects and wear a hat and wraparound sun glasses, then label the "herb" and use it as we would a drug, accepting the risk for the benefit it yields?
"The primary side effect of damage to the eye is through a phototoxic (light induced) reaction. The same reaction in the skin causes exaggerated sunburn. It hurts and so this is a signal for you to keep your skin out of the sun when using SJW. However, the damage to the lens (and retina) is not painful and you will not know you have damaged your eyes until it is too late"
“As far as protection, SJW absorbs both UV and visible light. A hat will be some protection but most damaging light to the eye is through reflective light. Wraparound sunglasses will primary block UV light. You need visible light to see and any sunglasses that block visible light will also prevent you from seeing. You can’t really protect your eyes from visible light.
“As for Benefit vs Risk: Trading blindness for a reduction in depression is not, in my opinion, an acceptable risk"
IB: How loud should the warnings be, and how certain are we it should be removed from the market? Is this a correlation or causation?
“Right out it may cause blindness in the presence of light, sunlight or artificial light. This could lead to blindness. I would label it like cigarettes, not hidden or subtle, that doesn’t scare anybody. No shades of grey. So minimally we need much better labeling, that’s more important than anything. Proper labeling is first and foremost before you pull off the shelf then people have a choice. If you want to go blind take it.
“In Germany and Switzerland, they sell supplements in specific herbal shops that are strongly monitored and regulated so you know what they say in the label is in the bottle.”
IB: I like your explanation of a sort of sunburn on the retina. Is that the simple way to describe what happens after ingesting SJW and exposure to light?
“Yes, in simple terms it produces an inflammation reaction similar to sunburn on the retina. (formal: produces reactive oxygen species which damage retinal tissues).
IB: Do we know if there is any safe dose, or any time period that one can avoid this damage?
“STW is not toxic, it is phototoxic but is damaging at low levels in the presence of UV and/or visible light.”
IB: Should it absolutely be taken off the market in all forms for everyone?
“I cannot make that call. I am not a regulator."
IB: Since your research began 10 years ago, why haven't we heard more about this in the mainstream media, FDA, alternative or complementary medicine community?
“There have been several reports in peer reviewed journals on drug interactions and SJW, and on skin phototoxicity. My work on ocular phototoxicity of SJW has been reported in public journals, such as: People's Pharmacy, New Scientist, ITV in England, Reuters.”
IB: While the study out last month talks primarily about cataracts, you also include macular degeneration. What is the difference?
“The mechanism of damage is the same, light + SJW = reactive oxygen species resulting in damage to retinal tissues as well as lens tissues. Visible Light reaches the human retina."
IB: What do you say to users of SJW?
“Try another complementary method for instance "Light Therapy" for Seasonal Depression. NEVER mix Light Therapy with SJW.”
IB: Can the FDA really regulate SJW given all that it has on its plate and no resources to do so? The natural/ alternative/ complementary /health food community is very sensitive to any FDA regulation so what do you forecast for SJW and are there any others that should be regulated?
“I do not comment on regulatory agencies. But the FDA is aware of phototoxicity to the skin and eyes of over-the-counter, herbs, supplements and prescription medications. They have just opened up a new center in Arkansas to study these problems.”
IB: The study out last month, can you comment on how it differs or echoes your work from 1999, 2004 and 2007?
“The study out last month is a clinical epidemiology study of human eyes. My studies are in vitro (cell) assays using human eye cells that predict potential ocular phototoxicity. In vitro studies come first to define the problems and then MD's continue with clinical studies represented by the paper you were discussing.”
IB: The assumption is that natural means safe and that herbs are harmless. But many people don't realize that modern day drugs are often extracted from herbs. What do you say to those who naively believe if it comes from the ground and not a pharmacy, it must be okay.
"Just because it is natural, does not mean it is safe"
IB: At the same time SJW seems to show some ability to highlight cancerous cells? Might there be some application for that in the future?
“Hypericin, the phototoxic agent in SJW, is being used clinically in Singapore to kill tumor cells. This is called photodynamic therapy (PDT), which is Dye + Light kills tumor cells. There are many different dyes that are used for this purpose.”
IB: Just sort of a curious question - if an herb has been used for centuries for its medicinal qualities, doesn't that give some credence to it?
“SJW had been used for centuries in Europe (England, Germany) where there was little intense sunshine, particularly in the winter. With the introduction of JET travel, many Europeans go to the south of Spain and Italy to relieve depression or for vacation. Americans go to Arizona or Florida for intense sunshine. So more people are now exposed to intense sunlight than at any previous time. Hence the increase in phototoxic reactions to SJW and prescription drugs.”
Robert says finding hypericin in the eye is fairly easy as it is fluorescent and can be seen when looking at the eye using a method called ocular fluorometry.
She is particularly concerned because symptoms of depression caused by Seasonal Affective Disorder, usually strikes during the winter when there are fewer hours of daylight.
Roberts advises those who take SJW to avoid light-box therapy and avoid spending any time out in the sun whether walking, sunbathing, bike riding, swimming, skiing or performing any other outdoor activity. #