This letter is intended to update you, your friends and your family on the current status of vitamins and micronutrients in eye care, and especially in the care of Macular Degeneration. Please be patient and take your time reading this summary report.
On October 12, 2001 the National Institutes of Health and National Eye Institute released their multicenter double-masked study of AGE-RELATED EYE DISEASES. The Ophthalmology profession has been awaiting this study for a long time. This study involved nearly 5,000 patients who were followed for a minimum of 5 years and some for as long as 10 years. Eleven Eye Centers in the United States participated. The study found (confirming what we have been saying for a long time) that high levels of antioxidants and minerals (zinc), when used by patients with Macular Degeneration, lowered their risk of progression of the disease by at least 25% in cases of intermediate stages and 19% in cases of advanced stages. In my experience the percentage of patients who stabilize and do not show serious loss is even greater when this antioxidant and mineral supplement program is instituted at the first recognition of the diagnosis.
In 2006, the same research group, which is based at NIH’s National Eye Institute, began a second study called AREDS2 to determine if they could improve the AREDS formulation. They tried adding omega-3 fatty acids, as well as the antioxidants lutein and zeaxanthin, which are in the same family of nutrients as beta-carotene. The researchers also tried substituting lutein and zeaxanthin for beta-carotene, which prior studies had associated with an increased risk of lung cancer in smokers. The study found that while omega-3 fatty acids had no effect on the formulation, lutein and zeaxanthin together appeared to be a safe and effective alternative to beta-carotene. AREDS-2 Study NIH study provides clarity on supplements for protection against blinding eye disease in an article published on May 5, 2013. NIH Study |
As Age-Related Macular Degeneration (ARMD) is such an important condition, in this paper we will attempt to explain what it is, and what we know about its prevention – – or at least about our ability to reduce its progression
In the United States and other industrialized countries, ARMD is a significant public health problem that leads to visual impairment or blindness. 14% of people age 55-64 already have evidence of ARMD. Nearly 20% of people age 65-74, and nearly 40% of people over 75 suffer from this condition! The majority (95%) of Macular Degeneration is represented by the so-called dry form, in which there are alterations in the retinal structure including the appearance of Drusen and pigment changes, but no fluid collections or bleeding. In the dry form of Macular Degeneration, there is a more severe variety called Geographic Atrophy, which is devastating to the central vision.
Five percent of all Macular Degeneration will convert to the so-called wet phase, in which a blister of fluid initially collects just under the retina with a fairly sudden change in visual acuity, followed by a hemorrhage (bleeding) into the blister with further decrease in vision. The conversion of the dry to wet phase of ARMD represents a practically irreversible and devastating loss of vision. Laser treatment, which is sometimes employed in the wet phase of Macular Degeneration, is not a very good solution to the problem. It is used as an attempt to arrest the extension of the bleeding and limit the amount of damage. It rarely, if ever, improves the vision significantly unless it is located far enough from the macula when initially discovered.
The retina has two parts: the peripheral retina and the macula. If you imagine the retina as a circle with a bull’s-eye at the center, the macula is like the bull’s-eye; it is very small. It is located near the optic nerve. The macula is that part of the retina responsible for our central vision. The large area of retina that surrounds the macula and makes up 95% of the retina is called the peripheral retina, or that part responsible for our side (peripheral) vision. Peripheral vision is what we refer to when we say, “I saw some thing out of the corner of my eye.” Because the peripheral retina cannot see detail clearly, we cannot use this vision to read, thread a needle, drive, or even recognize a face. If you see someone “out of the corner of your eye” you may be able to tell who the person is by their general shape, but you won’t be able to see the expression on that person’s face. In order to see fine detail, we must look straight ahead, using the macula. Though the macula makes up only a small part of the retina, it is one hundred times more sensitive to detail than the peripheral retina. The macula allows us to see tiny detail, read fine print, recognize faces, thread a needle, read the time, see street signs, and even see grains of salt being poured from a salt shaker.
If you look at the box on the next page, you will see the word “macula” in bold, red print in the center of the box. If you look directly at that word, you are looking at it with your macula. If you keep your eye fixed on the word “macula,” you are aware of the other words in the picture because of your peripheral vision, but you won’t be able to read them clearly. If you can read them clearly, it is because you are looking at those words instead of the word “macula.”
The only way to see detail is by using your macula and it must be healthy to work properly.
Since 1989, we at the Eye Associates have been evaluating the role of vitamins and micronutrients in modifying the natural course of Macular Degeneration. Evaluation of vitamins and micronutrients is a very difficult subject. To study each item in retail or wholesale vitamin products, amounts to studying the life of cells, cellular function and metabolism, and hundreds of biochemical reactions. As each micronutrient is investigated, a controversial issue about the product or its side effect profile may surface, which later prompts an updated recommendation. There are many examples of such conflicts, and it is precisely because of this, we set out to try and figure out which were the best preparations on the market for use in Macular Degeneration.
The eye tissue, especially the retina, has high levels of long-chained polyunsaturated fatty acids (PUFA).
These fatty acids, abbreviated PUFA, are subject to lipid peroxidation under the influence of oxygen and light. Retinal oxygen consumption is the highest in the body – even higher than oxygen consumption by the brain. Light exposure begins at birth and the eye is constantly bombarded by photons. The photons trigger reaction in the retinal tissue and these reactions are related to the wavelengths. When photons come from longer wavelengths such as red and infrared, the eye tissue is resistant and increasing number of photons are needed to trigger the reaction. When the photons come from shorter wavelengths, such as blue, violet and ultra-violet, sometimes even one photon will trigger the reaction. Reactions in the retinal tissue are oxidation reactions and they generate so-called reactive oxygen species. Reactive oxygen interacts with PUFA to form lipid hydro peroxide which in turn can damage cellular membranes in the cells in which they reside, leading to cell destruction. It is thought this is how Macular Degeneration occurs. There are additional, more complex, mechanisms in which lipofuscin is deposited in the retina causing so-called Drusen which are first found in the early stages of Macular Degeneration.
How does the retina protect itself from the harmful effect of light and oxygen?
Biological tissues that are susceptible to these oxidative attacks usually contain high concentration of endogenous antioxidants that protect the tissue by scavenging and neutralizing reactive oxygen species. Thus, in the retina we have high concentration of the following antioxidants: Vitamin E, Vitamin C, glutathione and glutathione-coupled enzymes such as superoxide dismutase and glutathione peroxidase. The human retina also contains two carotenoids called zeaxanthin and lutein. A strong antioxidant present elsewhere in the body, but not in the eye, is beta-carotene.
What do we know about the natural course of Macular Degeneration?
First of all, we know that genetics plays a significant role. If there is someone in the family who has had Macular Degeneration, the offspring or other blood relatives are more likely to develop the same condition. The condition is more common in light colored individuals who have light colored irises. This is thought to be due to the fact that melanin pigment in the eye protects against light effects.
There is significant evidence that points to smoking as being a very serious detrimental factor with increasing rates of Macular Degeneration in smokers. A person’s lifestyle, diet, and habits have been shown to play an important role in the pathogenesis of ARMD. There have been many epidemiological studies that have investigated ARMD, its causes, and its potential treatments or modes of prevention. Overall, there is significant evidence to support the association between low levels of certain vitamins/nutrients, including antioxidants, in ARMD.
Recommendations regarding wave length and light exposure
It appears from the literature that one aspect in protection against Macular Degeneration, as well as cataract, is afforded by avoiding severe and prolonged exposures to direct sunlight. Usage of ultraviolet filtering lenses is universally recommended for all prescription and nonprescription clear or dark glasses. In other words, no pair of glasses in this country should be manufactured without UV protection. Plastic lenses have the so-called UV400 filter that will remove or filter all of the wavelengths shorter than 400 nanometers. This should effectively remove the ultraviolet exposure.
Wavelengths between 500 and 400 nanometers can only be removed by an additional material that blocks blue light wavelength. This wavelength has also been found to be harmful to the macula.
There are several options available for combination of UV and blue light protection. Such lenses are not only excellent for protection of the macula, but they are also very helpful in assisting individuals in obtaining sharper vision by eliminating blue scatter. These lenses can be made with or without anti-reflective (anti-glare) coating. Our professional Opticians are very knowledgeable about your options and they will be happy to assist you in selecting the proper lens type.
What now?
Perhaps in the future we will find a way to safely, simply, and economically evaluate an individual’s level of antioxidants, vitamins, and minerals. If that were possible, we would then be able to provide individually tailored recommendations. At this time, however, such tests are expensive, cumbersome, not readily available, and not sophisticated enough to fully understand what levels are needed to be achieved. Therefore, at this time we must rely on general preparations of vitamins, micronutrients, and trace metals.
Horizon Complete
Dr. Kahle has developed Eye Associates’ own private label macular-protective nutrients, antioxidants combined with a multivitamin called Horizon Complete. Horizon Complete combines vitamins and minerals with other micronutrients and vitamins needed for the eye and body to assist in the prevention and control of Macular Degeneration as well as general overall body health. The development of Horizon Complete was in response to our realization that there was no single dietary supplement product that contained ALL of the components currently thought to provide benefit in ARMD as well as for the body.
The price of Horizon Complete is competitive. Because the product is inclusive of the important vitamins, minerals and nutrients noted in this article, 2 capsules per day are considered sufficient and additional purchases of bilberry, lutein, and a multivitamin, etc. are not needed.
Horizon Basic
Horizon Basic is just the AREDS2 macular support formulation and nothing else. Horizon Basic was added to our line of products to provide a less expensive product for people already taking their own favorite multivitamin.
Any additional inquiries regarding our Horizon Complete or Horion Basic products should be directed to Eric J. Kahle, M.D. at 6880 Palm Avenue, Sebastopol, CA 95472 or please contact us.
Eye Associates Medical Group: Eric J. Kahle, M.D.