AMD Research: Part 1

Age-Related Macular Denegation is a significant cause of vision loss that can often be managed and even improved through targeted nutritional support. It affects mostly people over age 50. While the precise cause of ARMD is not clear, oxidative damage is suspected as being a major factor. It strikes the elderly possibly due to poor diet and nutritional intake over a lifetime, less efficient absorption of nutrients and poor circulation as the body ages. The care needed by vision-impaired elderly could become overwhelming. Let’s take a look at some of the newest research in preventing macular degeneration, as well as treatment and support options.

Symptoms & Diagnosis

Central vision is possible because of the macula. It is a small, yellow-colored area at the center of the retina. Age-Related Macular Degeneration (ARMD) is the breakdown of the macula cells. It happens most often in people over age 50, and it is degenerative. While it does not cause complete blindness, it interferes with writing, reading, recognizing faces, cooking, driving, and other daily activities.

One common home screening tool is the Amsler test. Regular visits to the eye doctor are important for everyone in this age group.

There are two forms of ARMD.

1. “Dry” macular degeneration affects 90% of people with ARMD. Tiny fatty deposits called “drusens” form on the macula, damaging the macula cells.
2. “Wet” MD, also called choroidal neovascularization, means that new blood vessels develop near the macula. It may develop when dry ARMD is not managed through diet, exercise and targeted supplementation. Vision deterioration can be swift if left untreated by your eye doctor.

Standard Treatment and Support for Macular Degeneration

Macular Degeneration is not curable, so the focus is on slowing its progression and maintaining healthy vision.

For Wet Macular Degeneration, these treatments are available only from a medical professional:

• Anti-angiogenic drugs are injected into the eye on a regular basis to stop new blood vessels from developing. (See Anti-VEGF Therapy below)
• High-energy laser therapy destroys abnormal blood vessels.
• Photodynamic laser therapy uses a medication plus a cold laser to destroy abnormal blood vessels.

This eye disease responds particularly well to nutritional support:

1. Leafy green vegetables, which are rich in carotenoids.
2. Vitamins C and E, beta-carotene and zinc (in a specific dose – see AREDS))
3. Lutein and zeaxanthin
4. Omega 3 fatty acids^{1 2}

Low vision aids help ARMD patients make the most of their remaining vision.

Experimental treatments such as implants and surgical approaches are underway.

Research into Laser Therapy

A pilot study³ looked at panmacular subthreshold diode micropulse laser (SDM) for preventing further damage from retinal diseases including macular degeneration. This technology uses low-intensity, high-density lasers. The study found improvements in macular sensitivity and mesopic contrast visual acuity.

Research into Microcurrent Stimulation

Medical professionals use microcurrent stimulation for wounds, pain and transplants. Some macular degeneration patients find that it improves their condition. A small study⁴ looked at 25 eyes with dry age-related macular degeneration, and 6 eyes with wet age-related macular degeneration. In most of the patients with the “dry” type of ARMD, they saw significant increases in visual acuity. Twice as many had improvements (usually large) versus deterioration (usually small). The “wet” sample size was small, but one had improvement and none had declines. See our blog post about microcurrent stimulation.

Research into Lutein and Zeaxanthin

The two carotenoids lutein and zeaxanthin are crucial to the macula, which is colored yellow by their pigments. This protects the retina from blue-to-UV light. A meta-study⁵ reviewed the research on these nutrients in December 2015. They looked at several eye diseases, including macular degeneration.

• Most observational studies on dietary intake of zeaxanthin and lutein found that high intake was associated with decreased risk of macular degeneration.⁶.
• One study of blood levels of these nutrients found no correlation; another study with 360 patients found a significant correlation. ⁷
• Measuring the pigment levels in donated eyes from cadavers found a strong correlation between lower levels of macular pigment and AMD. ⁸ Other studies have measured macular pigment optical density on living subjects; they found that getting more carotenoid-rich foods in the diet resulted in more pigment. Also, more lutein and zeaxanthin in the blood correlated with more pigment. The amount of pigment declines with age in healthy subjects, and was significantly lower in patients at risk of AMD. ⁹
• “After the established correlation between the risk of AMD and low serum and retinal concentrations of [lutein] and [zeaxanthin], supplementation trials were initiated. These trials have shown extremely consistent results as compared to any other single nutrient supplementation trial.” ¹⁰ This meta-study cites a large body of research on how supplements have a significant impact on macular degeneration.

Research into Mesozeathin

Mesozeathin is a carotenoid similar to lutein, and is found in the center of the macular where we get our most detailed vision. It occurs naturally in microalgae and sea creatures that consume the algae such as salmon, shellfish, and krill. A 2015 study showed supplementing daily with mesozeaxanthin significantly increased macular pigment – pigment that is found to be compromised in those with macular degeneration. ¹¹

Research into Vitamin D3

There is a genetic risk for ARMD related to an inflammatory response to the presence of protein and fatty build-ups in the eye. Vitamin D has anti-inflammatory and anti-angiogenic properties. A study found a deficiency of vitamin D increased risk, especially in individuals with the highest genetic risk.¹² See related Vitamin D research.

Research into Omega-3 Fatty Acids

A review of the research¹³ said that in well-designed studies, omega-3 fatty acids had no effect on ARMD.
However, many studies on omega-3’s found the opposite. For example, a significant study over 10 years¹⁴ found women with the highest intake of an omega-3 fatty acid (docosahexaenoic acid) had a relative risk two-thirds lower than women with the lowest intake. Eating at least one serving of fish per week had a similarly lower risk versus having fish once a month.

Giving omega-3 to animals that have AMD reduced the rate of growth of lesions, and improved the lesions in some cases.¹⁵

Research into Astaxanthin

Astaxanthin is a powerful antioxidant in the eyes that helps prevent damage due to exposure to sunlight, reduces DNA damage, and in many ways is more powerful as an antioxidant than Vitamin C, Vitamin E and betacorten. A study on animals¹⁶ found that retinas were protected from light-induced damage with sufficient amounts of this antioxidant.

In our next article, we will examine more recent research into macular degeneration, in the areas of genetics, smoking, green tea, exercise, bilberry, and the Mediterranean diet.