An intriguing presentation about the possible link between age-related macular degeneration (AMD) and processed food consumption literally caught my eye. As presented in the featured video, ophthalmologist Dr. Chris Knobbe, founder and president of the Cure AMD Foundation, suggests the common assertion macular degeneration is caused by aging or genetics is a mistaken one.
Given the reality macular degeneration has gone from being an extremely rare disorder more than a century ago to one that is found at increasingly alarming rates in developed countries around the world, Knobbe points to higher intakes of processed food — not aging or genetics — as the root cause.
He presented his research findings at the 2018 Ancestral Health Symposium, held in Bozeman, Montana. Knobbe asserts the same people known to consume the most processed food not only develop AMD, but are also more likely to be affected by cancer, heart disease, hypertension, obesity, Type 2 diabetes and stroke.
What Is Macular Degeneration?
According to the American Academy of Ophthalmology (AAO), 1 macular degeneration results when the part of your retina called the macula becomes damaged, causing you to lose your central vision. If you have AMD, you cannot see fine details whether close or far, but your peripheral (side) vision remains normal.
The BrightFocus Foundation defines AMD as "an irreversible destruction of the macula, which leads to loss of the sharp, fine-detail, 'straight ahead' vision required for activities like reading, driving, recognizing faces and seeing the world in color." 2
Knobbe notes your macula measures 6 millimeters (mm), or about one-fourth of an inch, across and accounts for the central 10 degrees of your vision. "Arguably, this is the most important 6 mm in our bodies," he asserts. 3 About macular degeneration, the AAO says: 4
- It is a leading cause of vision loss in people 50 years and older
- About 80 percent of people with AMD have the dry form, which is characterized by the thinning of parts of your macula, as well as the growth of tiny clumps of protein called drusen, which causes you to slowly lose your central vision
- Wet AMD is a less common but more serious form of vision loss because it causes new, abnormal blood vessels to grow under your retina, which may leak blood or other fluids that cause scarring of your macula
- Wet AMD accelerates vision loss more quickly than dry AMD
- Blurry vision may be the first sign of macular degeneration; regular visits to an ophthalmologist can help you identify early warning signs of the disease
Who Is Affected by Macular Degeneration?
AMD is no respecter of persons. A couple of well-known sufferers of the disease are legendary British actress Dame Judi Dench, 5 83, and American actress and comedian Roseanne Barr, 6 66, both of whom have spoken publicly of their vision problems.
Sadly, Dench and Barr are not outliers; they're just two of the estimated millions of people worldwide affected by this potentially devastating disease. According to Knobbe and experts at the BrightFocus Foundation, AMD is: 7 , 8
- The leading cause of irreversible vision loss in people over the age of 65 who live in developed countries
- A leading cause of irreversible blindness and visual impairment worldwide — the number of people living with AMD is expected to reach 196 million worldwide by 2020 and increase to 288 million by 2040
- Known to affect as many as 11 million people in the U.S., this number is expected to double by 2050
Though Knobbe disagrees, the link between aging and macular degeneration is based on statistics suggesting your risk of contracting the disease increases from 2 percent for people ages 50 to 59 to nearly 30 percent for those age 75 or older. 9
The Causes of Macular Degeneration
Traditional ophthalmology associates AMD to aging, hence the name "age-related macular degeneration," and more recently has also suggested genetics may be a contributing factor. The AAO claims you are also more likely to develop AMD if you are: 10
Age 50 or older
Eating a diet high in unhealthy fats
Known to have a family history of AMD
In contrast to conventional wisdom, Knobbe, as discussed in the featured video, believes man-made, processed foods are the primary culprit, although he leaves room for a possible genetic link, too.
His beliefs, which were sustained through a combination of investigative journalism, interviews and research, culminated in the 2016 publication of his book "Cure AMD — Ancestral Dietary Strategy to Prevent & Reverse Macular Degeneration."
In addition, a summary of Knobbe's work was published in the journal Medical Hypotheses in 2017. 11 While the lifetime risk of contracting AMD was about zero in 1900, he says, by 1992, it was believed to affect 1 in 3 people over the age of 75.
Today, he claims 20,000 new cases of AMD are diagnosed worldwide every day. Based on his research, Knobbe states, "I believe, 100 percent, that this disease is caused by diet and diet alone. Now, no question, genetics play a role, but environment pulls the trigger. That 'environment' is our diet."
Processed Foods Implicated for Skyrocketing Rates of Macular Degeneration
Based on his research, Knobbe asserts the key to addressing the skyrocketing rates of AMD must focus on decreasing our intake of processed foods and returning to a so-called ancestral diet. This, he notes, may be our best means of preventing, and possibly treating, the disease.
Knobbe defines an ancestral diet as any eating program that existed on the planet prior to 1880, when the first processed foods — namely, refined white flour and polyunsaturated vegetable oils — were made available. Trans fats , he notes, were first introduced in 1911.
After noting the Western diet has more than 600,000 food items you can put on your plate today, Knobbe said, "When we break this down, what we know is 63 percent of these food items are made up of those refined, processed, nutrient-deficient foods in the form of added sugars, refined white flour, polyunsaturated vegetable oils and trans fats."
He calls the dependence on processed foods "the recipe for metabolic disaster and physical degeneration." Drawing from the work of the late Weston A. Price, 12 Knobbe calls out the following problematic categories of processed food, which Price referred to as the "displacing foods of modern commerce":
Macular Degeneration: Another Disease of Western Civilization?
Given the increased use of these so-called modern foods during the past 140 years, Knobbe says it is no surprise higher intakes of them have been linked to what he calls "diseases of Western civilization."
On the list are well-known conditions such as Alzheimer's disease , autoimmune disorders, cancer, heart disease , metabolic syndrome, obesity and Type 2 diabetes . Knobbe says he had somewhat of an epiphany in 2013 when he posed this question to himself: "Could AMD be another 'disease of Western civilization'?"
After comparing the historical rates of incidence for AMD as it related to the increased availability and consumption of sugar and vegetable oils, Knobbe began to surmise AMD indeed may be linked to the increased consumption of processed food. "After just 30 years of consuming these processed foods, we are at epidemic proportions of chronic disease," he observes.
In Japan, since the 1970s the increased use of vegetable oils has spiked the incidence of AMD. Said Knobbe, "The rate of AMD [in Japan] was at 0.2 percent prevalence in 1970. By 2007, their prevalence was 11.4 percent. That's a 57fold increase in the prevalence of AMD in just 30 years. We can't possibly explain that with genetics and aging."
When comparing rates of AMD in Nigeria, Knobbe noted the availability for processed food in major metropolitan areas as a factor in the 3.2 percent rate of AMD incidence in cities. He contrasted that rate to AMD prevalence among Nigerians living in a rural area where there was no access to processed food. It was just 0.1 percent.
Poverty Linked to Vision Loss; AMD Not a Disease of Aging or Genetics
Using data from the U.S. Centers for Disease Control and Prevention (CDC), Knobbe observed links between poverty and chronic diseases such as the prevalence of severe vision loss, including AMD. Southern states had higher incidence of both poverty and severe vision loss. About the link between the two, Knobbe states:
"Why is poverty an issue? Because in [the U.S.] you can purchase about 2,000 calories worth of processed food for about $3.50. That same 2,000 calories coming from whole foods … costs you about $13 or more. It's a sad fact … but it's a reality."
If AMD is all about aging, we would expect to see that people in the south, where the highest rates of severe vision loss exist, have the longest life spans. However, the data do not bear that out, notes Knobbe.
Life expectancy in the south is actually lower than the national average, he says. "Where we have the greatest vision loss, including the most macular degeneration, we have the shortest lives. This is not consistent with the theory that macular degeneration is a disease of aging."
As such, he concludes, "Macular degeneration is not a disease of aging. It's not a disease of genetics. It is a disease of processed food consumption. And that results in more chronic, metabolic and degenerative disease, more macular degeneration and earlier death." On his Cure AMD Foundation website, Knobbe writes: 13
"Every shred of evidence I can find supports the hypothesis that it is the 'displacing foods of modern commerce' that are the primary and proximate cause of AMD. The prevention of this disease — as well as the treatment — is to remove those elements from the diet, and consume only … our own native, traditional diets."
How to Help Prevent Macular Degeneration
Most certainly, eating nutrient-dense foods is the best way to preserve your eyesight. Knobbe recommends a whole food diet as the best antidote to vision problems such as macular degeneration. While a change in diet cannot reverse an established case of AMD, it can be helpful as a preventive measure before the onset of the disease.
Knobbe suggests you eat a diet "rich in meats, fish, eggs, fruit, vegetables, some nuts and seeds, and perhaps critically, some 'sacred' foods of our ancestors, such as beef or chicken liver, fish eggs (roe) … or pastured butter." 14 He adds, "My preference is to choose the wild or pastured versions of animal meats and eggs whenever possible, and organic versions of … fruits and vegetables." 15
While I agree with most of Knobbe's recommendations, for optimal health you will want to limit your daily fructose consumption, including fructose from whole fruit, to 25 grams (g) or less if you are healthy. If you are dealing with a chronic illness such as cancer or diabetes, you'd be wise to further restrict your fructose intake to 15 g until your condition improves.
Beyond this, animal-based omega-3 fats help improve cell structure and protect your sight, while whole foods high in anthocyanins and bioflavonoids help protect your cells from free radical damage. Lutein and zeaxanthin, potent carotenoid antioxidants found in leafy greens like kale and spinach as well as organic, free-range egg yolks, are also known for their role in promoting healthy vision.
It is believed the presence of lutein, zeaxanthin and meso-zeaxanthin in your macula blocks blue light from reaching the underlying structures in your retina. As such, they help reduce your risk of light-induced oxidative damage that could lead to macular degeneration. 16
Natural antioxidants like beta-carotene and vitamins C and E also support your eyes, as does astaxanthin, which is found in certain marine plants and animals, including krill oil. Learn more about the foods your body needs to protect your vision in my previous article " Eat Right to Protect Your Eyesight ."
Other Ways to Reduce Your Risk of Macular Degeneration
Beyond your diet, blocking blue light may help reduce your risk for macular degeneration, while also improving your sleep. Below are a few tips on how to limit your exposure to blue light:
- Use blue-blocking glasses — Blocking blue light aids in regulating your internal body clock to control sleep patterns. Also, it reduces the negative effect high energy wavelengths have on your macula. I recommend you wear blue light-blocking glasses after 7 p.m. or when the sun sets.
- Install blue-blocking software on your digital devices — If you are not a fan of wearing blue blockers, you might want to try Iris , a free software program that can automatically adjust your screen settings to reduce blue light. I have used Iris for many years and highly recommend it.
- Replace LED lights with incandescent bulbs — Many of the LED lights sold today emit a large portion of aggressive blue light, which is why I advise you to use incandescent bulbs instead. To learn more about how to protect yourself, read my article " How LED Lighting May Compromise Your Health ."
- Sleep in total darkness — To achieve a deeper, more restorative sleep, you must protect your eyes from light at night. Using a sleep mask or room-darkening shades are two easy solutions, and be sure to keep electronic devices out of your sleeping area.
While the rates of macular degeneration continue to climb, you can take steps today to reduce your risk of this debilitating eye disease. As Knobbe suggests, eliminating processed food from your diet is among the best preventive measures against macular degeneration.
While conventional medicine may try to convince you AMD and other chronic illnesses are simply a factor of aging or genetics, two areas over which you have little control, the truth is, you are not helpless to affect positive change.
Based on his research, Knobbe concluded the term AMD is a misnomer. Rather than calling the loss of central vision "age-related macular degeneration," he asserts it would be more aptly named "diet-related macular degeneration" or "DMD." 17 While aging is not something you can control, you most certainly have some measure of control over your diet and, therefore, your eye health, too.