Keto and Macular Degeneration: Can a Ketogenic Diet Help?
You know a ketogenic diet can help with a multitude of conditions from Alzheimer’s to epilepsy. What about macular degeneration? Can a ketogenic diet improve eye health?
Macular degeneration is a common eye condition, particularly in those over age 60. A growing number of eye doctors are recommending high-nutrition and ketogenic diets to their patients and seeing impressive and drastic results. Turns out that just like every other part of your body, what you eat also affects your eye health. Let’s look at eye health, keto, and macular degeneration.
What Is Macular Degeneration?
Macular degeneration is an eye condition involving deterioration of the central part of the retina—the inside back layer of your eye [1].
Symptoms of macular degeneration include:
- Change in color perception
- Blurred vision
- Visual distortion
- Difficulty seeing in darker lighting
- Loss of central vision with blurry spots in middle of vision
Macular degeneration is a leading cause of vision loss. The cause of macular degeneration isn’t exactly clear but certain factors might increase the risk of developing this condition, such as:
- Aging
- Hypertension
- Obesity
- Smoking
- A genetic link
- Family history
How Is Macular Degeneration Usually Treated?
Doctors usually recommend lifestyle changes like diet and exercise, quitting smoking, and weight loss, if necessary. In some cases, doctors suggest photodynamic therapy, anti-VEGF therapy, or laser surgery to treat macular degeneration. These treatments can slow vision loss for some people.
What Diet Is Recommended for Macular Degeneration?
Doctors are recommending several diet tips and eating plans to help prevent vision loss and the progression of macular degeneration. Here are some of the most commonly recommended diet tips by notable ophthalmologists and authors like Dr. Lylas Mogk:
Eat Fatty Fish
Fatty fish is high in omega-3 fatty acids that reduce inflammation and promote eye health.
Eat Dark Leafy Greens
Dark leafy green veggies like collard greens, kale, and spinach contain lutein, which protects the macula of your eye from sun damage.
Avoid Packaged and Processed Foods and Artificial Fats
Packaged and highly processed foods usually contain trans fats, which are artificial fats. Packaged foods also tend to contain lots of omega-6 fatty acids in the form of vegetable or grain-based oils like canola, which can throw off your balance of omega-3 and omega-6 fats. You want more omega-3s compared to omega-6s. Check out our article for more info on the different types of omegas [2].
Avoid Fried Foods, High Glycemic Foods, and Refined Carbohydrates
Avoid refined carbohydrates like bagels and pasta and high glycemic foods like cookies, donuts, and other sweets.
Eat Fruits and Veggies
Most conventional doctors and ophthalmologists recommend a diet rich in colorful antioxidant-rich fruits and veggies and foods providing omega-3 fatty acids. A diet rich in veggies and fruits has been shown to decrease the risk of diseases like heart disease, cancer, and stroke. Vitamins C and E, Zinc, omega-3s, and carotenoids like lutein and zeaxanthin are considered pivotal when it comes to vision health due to their anti-inflammatory and antioxidant properties [3] [4].
Macular degeneration could be partly caused by oxidative stress in the retina and overexposure to UV light. Zeaxanthin and lutein are two carotenoids that act as antioxidants and filter short-wavelength light linked to photochemical damage. Studies reveal diets including more zeaxanthin and lutein are associated with a lower risk of age-related macular degeneration (AMD). Antioxidant vitamins A, C, and E, are known to combat oxidative stress.
Research shows people with AMD might experience a delay in the disease progression with multivitamin, antioxidant, and mineral supplementation [5].
Mediterranean Diet
Research highlights that a Mediterranean style of eating is linked to a lower risk of progression to advanced AMD. Olive oil is a staple in the Mediterranean diet and an interesting study found a decreased risk of late AMD among olive oil users aged over 72 years. Olive oil is rich in polyphenols and monounsaturated fatty acids [6] [7].
Keto and Macular Degeneration: Why a Ketogenic Diet Might Help
Many doctors and ophthalmologists would answer with a resounding yes, a ketogenic diet can help with macular degeneration due to several reasons.
So far, the research is limited but promising, and more studies focusing specifically on keto and macular degeneration are needed. For example, one study concluded there was notable improvement for different eye conditions, including macular degeneration, when a ketogenic diet was paired alongside photobiomodulation therapy [8].
A keto diet has already been proven to improve other eye conditions like glaucoma and diabetic retinopathy, so it’s likely it could also be effective for macular degeneration [9]. An animal study revealed that a ketogenic and low-protein diet slowed retinal degeneration [10].
Stabilizing Blood Sugar Can Help
A low-glycemic diet has been shown to improve macular degeneration. The risk for macular degeneration is greatly minimized by eliminating unnecessary sugars from the diet, which is a given when you’re on a keto diet. Stabilizing blood sugar levels can protect your eyes from vision loss and mitochondrial diseases. A low-carb diet like keto is low glycemic and avoids those harmful sugars that can damage your eyes over time and drag you onto the blood sugar rollercoaster that can lead to metabolic syndrome [11].
Being in Ketosis May Improve Nerve Health
Damage to the optic nerve can lead to visual impairment or blindness. Brain derived neurotrophic factor (BDNF) are proteins that might play a role in protecting eye health even after the optic nerve is damaged, but more studies are needed. Essentially, researchers have been able to restore partial sight in blind mice using injections of BDNF directly into the eye. People with glaucoma, diabetic retinopathy, and macular degeneration have a deficiency of BDNFs, making them more vulnerable to visual problems and neurodegeneration. Increasing ketones with a ketogenic diet stimulates your body’s own natural production of BDNF [12] [13] [14].
You can also raise ketones and BDNFs by eating coconut oil, which is composed of medium chain fatty acids (MCFAs) that are automatically converted into ketones.
Assuming you’re not eating a dirty keto diet and you’re consuming a diverse range of natural foods, you should be protecting your vision. A well-formulated nutrient-dense ketogenic diet has plenty in common with the Mediterranean diet, minus the heavier carbs like grains.
What About Saturated Fat?
The jury is out when it comes to fatty meats like red meat and burgers and fats like butter and cream. There isn’t a consensus, but keto ophthalmologists and keto experts usually encourage the consumption of healthy natural saturated fats you find in coconut oil, grass-fed butter and beef, and mackerel! Did you know that mackerel actually has more saturated fat than a typical T-bone steak? While saturated fat has been demonized over the years, lately we’ve seen it exonerated.
A keto diet ditches harmful sugars and high glycemic foods and includes foods like fish and leafy greens, providing you with nutrients to enhance eye health, such as lutein and omega-3s. You might also try a lower carb version of a Mediterranean diet to see how it affects macular degeneration.
References
American Foundation for the Blind (AFB). Macular Degeneration, Macular Degeneration Guide | American Foundation for the Blind (afb.org)
American Macular Degeneration Foundation (AMDF). Important Nutrients, Important Nutrients - American Macular Degeneration Foundation
United States Department of Agriculture (USDA) My Plate. Vegetables, Vegetables | MyPlate
Johnson, R. H. (2013). Nutrients for the aging eye. Clinical Interventions in Aging, 8, 741-748. https://doi.org/10.2147/CIA.S45399
Linus Pauling Institute. α-Carotene, β-Carotene, β-Cryptoxanthin, Lycopene, Lutein, and Zeaxanthin. Carotenoids | Linus Pauling Institute | Oregon State University
American Macular Degeneration Foundation. Best Food and Recipes Good for Macular Degeneration, Best Food and Recipes Good for Macular Degeneration - AMDF
Carneiro, A., & Andrade, J. P. (2017). Nutritional and lifestyle interventions for age-related macular degeneration: A review. Oxid Med Cell Longev, https://doi.org/10.1155/2017/6469138
United States National Library of Medicine. Photobiomodulation and Ketogenic Diet for Treatment of Mid-Peripherary Retinal Disorders for Alzheimer’s Disease Prevention. Photobiomodulation & Ketogenic Diet for Treatment of Mid-periphery Retinal Disorders for Alzheimer's Disease Prevention - Full Text View - ClinicalTrials.gov
Mount Sinai Health System (2020). Low-Carbohydrate Diet May Be Associated With Lower Risk of Glaucoma. Low-Carbohydrate Diet May Be Associated With Lower Risk of Glaucoma (eyewire.news)
Ryals, R. C., Huang, S. J., Wafai, D., Bernert, C., Steele, W., Six, M… Pennesi, M. E. (2020). A ketogenic & low-protein diet slows retinal degeneration in rd10 mice. Translational Vision Science & Technology, 9(18), DOI: https://doi.org/10.1167/tvst.9.11.18
National Institutes of Health (NIH). How Diet May Affect Age-Related Macular Degeneration, How diet may affect age-related macular degeneration | National Institutes of Health (NIH)
Mey, J., & Thanos, S. (1993). Intravitreal injections of neurotrophic factors support the survival of axotomized retinal ganglion cells in adult rats in vivo. Brain Res, DOI: 10.1016/0006-8993(93)90695-j
Quan, M. Z., Kosaka, J., Watanabe, M., Wakabayashi, T., & Fukuda, Y. (1999). Survival of axotomized retinal ganglion cells in peripheral nerve-grafted ferrets. Invest Opthalmol Vis Sci, 40(10), 2360-6.
Ola, M. S., Nawaz, M. I., El-Asrar, A. A., Abouammoh, M., Alhomida, A. S. (2013). Reduced levels of brain derived neurotrophic factor (BDNF) in the serum of diabetic retinopathy patients and in the retina of diabetic rats. Cell Mol Neurobiol, 33(3), 359-67.
