Fun fact: Did you know that we don’t really see with our eyes? We actually see with our brains.
Similar to a camera, the eye captures wavelengths of light but cannot process them. Just as a camera focuses light rays onto film or converts them into a digital format to create an image, the eye must convert light into electrical energy. These electrical signals are sent through the optic nerve to the brain for processing, which is what allows us to see images.
The eye and brain are interconnected on many levels: Anatomically, the eye is a direct extension of our brain and considered part of the central nervous system. Beyond this structural connection, 30% of our brain is dedicated to the functioning of our visual system. These visual pathways within highly specialized parts of the brain enable us to see gross and fine resolution, shape, color, depth, contrast, and motion.
Our brain is also responsible for moving our eyes and using visual input from our eyes to maintain balance. So, as you can see (pun intended!), the eye-brain connection is quite fascinating and complex.
How eye health affects the brain.
Though the eye is often considered a window to our soul, the eye is truly a window to our brain health. Many neurological conditions involve vision and can be discovered through the eyes, such as:
- Brain tumors
- Neurodegenerative conditions, including Alzheimer’s and Parkinson’s
- Autoimmune conditions such as multiple sclerosis (MS), neuromyelitis optica (NMO), and myasthenia gravis (MG)
- And many more.
The field of neuro-ophthalmology is dedicated to studying and managing this complex interplay between the brain and the eye. As a neuro-ophthalmologist over the past 20 years, I’ve diagnosed thousands of patients with neurological conditions, simply through a detailed eye exam.
My patients often come in with a range of visual symptoms: vision loss in one or both eyes, trouble focusing, flashing lights, inability to read or use a device, eye pain, headaches, light sensitivity, double vision, a droopy eyelid, and many other more unusual complaints.
My initial training in traditional Western medicine taught me how to treat these neuro-ophthalmic disease processes using medications or even surgery. However, studying integrative and functional medicine transformed my approach: Many types of neuro-ophthalmic diseases are preventable or can be treated naturally.
How to prevent eye and brain disease.
In my experience, I’ve found it’s essential to identify and address the root cause, in order to best treat eye and brain disease. For most neuro-ophthalmic conditions, this means oxidative stress, mitochondrial dysfunction, inflammation, and toxin exposure. After identifying the root cause, I initiate treatment strategies based on the science of nutrition, botanicals, essential oils, lifestyle modification, and supplements.
Because eye health and brain health are so closely linked, I have found that the strategies used to support one organ are also effective for the other, and vice versa. Here are my top five recommendations to maintain a healthy visual system:
Nutrition is the foundation to support healthy vision. Because the delicate tissues of our eye and brain are susceptible to oxidative stress, mitochondrial dysfunction, and inflammation, an antioxidant and anti-inflammatory diet is essential.
One of the best ways to accomplish this is through a plant-rich diet. I recommend at least 5 cups of colorful vegetables and fruits daily to provide the diversity of vitamins, minerals, antioxidants, and bioflavonoids needed to maintain good vision. In particular, the antioxidant carotenoids—lutein, zeaxanthin, meso-zeaxanthin, and astaxanthin—have demonstrated benefits for both eye and brain health.
In addition to antioxidants, the B vitamins that support mitochondrial health, namely thiamine (B1), riboflavin (B2), niacin (B3), and cobalamin (B12), are essential, as is regular intake of anti-inflammatory nutrients such as omega-3 fatty acids and vitamin D.
Adequate hydration is paramount to a healthy visual system. Unfortunately, I have seen countless cases of eye or brain stroke and migraine triggered by dehydration.
Hydration allows for adequate oxygenation to supply the high metabolic demands of the eyes and brain. Hydration also supports the delivery of nutrients to the eyes and brain and allows for the cleaning of tissues.
My typical recommendation to determine optimal hydration is this simple equation: Take your body weight in pounds and divide by two. This number is approximately how many fluid ounces you should have daily. (Be sure to check with your health care provider about your personal hydration needs, particularly if you have a history of cardiac or kidney disease.)
Another gauge of whether you are well-hydrated is the color of your urine. It should be a light yellow straw color—if your urine is dark yellow, orange, or even brown, you are likely dehydrated.
Keep in mind that hydration does not have to be only water; other liquids such as coconut water, plant milk, decaf tea, or flavored seltzer can count toward this goal. Just be sure to avoid sugary drinks that may raise blood glucose, or too much caffeine that can lead to dehydration. You may also achieve adequate hydration by eating foods with high water content. Many vegetables and fruits are hydrating and provide fiber to retain water and aid digestion and elimination.
Numerous studies have suggested that individuals who exercise regularly have a lower risk of vision-threatening diseases, such as macular degeneration, glaucoma, and diabetic retinopathy. In addition, regular movement and exercise also help keep neurodegenerative conditions, such as Alzheimer’s disease, at bay.
My usual recommendation is to do various forms of exercise, for up to eight to 10 hours weekly. Within this overall quota, 150 minutes of weekly aerobic activity is essential to supply adequate blood flow and maintain oxygenation to the brain and eye. Even light forms of activity such as deep breathing, housework, stretching, yoga, and tai chi can be very beneficial.
4. Limiting environmental toxin exposure
Exposure to toxins, such as cigarette smoke, air pollution, heavy metals, household chemicals, and mold, may increase the risk of eye and brain conditions. Limiting exposure to environmental toxins is a key prevention strategy for eye conditions such as dry eye, cataract, macular degeneration, and optic neuropathy.
In my experience, therapeutic foods that promote elimination—such as cruciferous vegetables and fiber-rich foods; botanicals such as turmeric, dandelion root, or milk thistle; and chelating agents such as charcoal—have proved helpful for my patients.
5. Protecting against short-wavelength blue light
Blue light is comprised of short-wavelength, high-energy light rays. Blue light has been associated with several adverse health and ocular effects, including migraine headaches, sleep disturbances, attention issues, and digital eye strain. Fortunately, there is no evidence to show that excessive blue light exposure leads to permanent vision loss.
Most of the blue light to which we are exposed comes from the sun: This is beneficial blue light that helps regulate our sleep-wake cycle and mood. However, artificial sources of blue light from screens, monitors, and even energy-saving bulbs can lead to health and eye issues.
Boosting the eye’s natural blue blockers found in the retina—the macular carotenoids, lutein, and zeaxanthin—through diet and supplementation is the cornerstone of preventing blue-light-related issues. Moderating blue light exposure using screen filters, light-filtering apps, blue-blocking lenses, and smart bulbs can also be quite beneficial, particularly two hours before bedtime.
The visual system relies on both eye and brain health to maintain good eyesight. Therefore, we must be proactive in warding off the common root causes of eye and brain disease: oxidative stress, mitochondrial dysfunction, inflammation, and environmental toxins.
In my experience, the most effective preventive and therapeutic protocols for eye and brain health are integrative strategies that include nutrition with essential nutrients, hydration, regular movement, elimination, and modulation of blue light exposure. Incorporating these five key strategies can help you promote healthy vision for the years and decades to come.