Written by Dr. Jewel Alfoure, ND
Windows to Optimal Health
- Eyes are an extension of the brain (1)
- Eye health is highly connected to overall health
- Conditions that affect the eye include eye strain, glaucoma, cataracts and macular degeneration
The eyes are functional organs that maintain the sleep-wake cycle, facilitate safety and make life much more enjoyable.
Those little passageways into the world of visible electromagnetic radiation (light waves that influence vision) are highly complex, extremely evolved parts of the brain.
Though their full complexity is not completely understood, it can be appreciated and respected.
Our eyes can suffer from many conditions including eye strain, glaucome, cataracts and macular degeneration (2).
Additionally, some chronic conditions can affect eye health significantly. Conditions that affect vascular health including hypertension (increase in blood pressure) and diabetes (increase in blood sugar) can significantly impact vision (3,4).
Ensuring overall health may be the best way to insure optimal eye health, however, there are some natural compounds that can ensure optimal eye health and delay degeneration.
Detoxing the eyes
- There are three neurological structures in the brain with photoreceptors (5,6)
- Build up of toxic metabolites directly impacts eye health and functionality (7) Glutathione:
- Detoxify the fluid of the inner eyes
- Maintains fluid outflow in glaucoma
- Insures lens transparency (8)
The eyes are a very active component of the brain. They are always active and responding to the visual stimuli (5). Any organ that is very active is in danger of a buildup of toxic metabolites.
The buildup of toxic metabolites can impede healthy function and make the organ less effective at carrying duty.
One of the best natural detoxifying agents in the body is glutathione (7),
Glutathione is a chemical that breaks down the metabolites. It is produced by all living cells, though glutathione is usually associated with liver detoxes.
The problem with glutathione is that it has very poor bioavailability which means that even if it is introduced in the body, it is poorly absorbed (9).
Studies show that glutathione plays a positive role in conditions such as cataracts, glaucoma, retinal disease and diabetic blindness (10, 11).
Glutatione’s poor absorption is mitigated by giving the body its precursor n-acetyl cysteine (NAC).
NAC is a sulfur rich amino acid that can boost the natural production of glutathione (13).
Put Those Shades On, Internally!
- Eating greens significantly improves overall health as well as eye health (14, 15)
- Those with higher greens intake, had higher visual acuity (16)
- Vitamin A is important for maintaining healthy night vision (17).
Some pilot studies and anecdotal evidence show that increasing the amount of leafy greens in the diet can help maintain healthy vision (16).
Those studies/ stories depend on the fact that the back curtain in the eye that maintains the inside of the eye dark enough for the “cinema projector” to play “motion pictures” optimally is kept dark with pigments like lutein and zeaxanthin.
Those pigments act like a filter on the retina. The millions of light receptor cells in the retina require the darkness to function optimally.
Animal studies show that the middle yellow pigmentation in the retina is significantly diminished in a diet deprived of lutein and zeaxanthin (17,18).
In the case of dark vision, it is established that beta carotene is converted to vitamin A in the liver. It makes its way into the retina where it is converted into rhodopsin. Rhodopsin is the night-vision chemical (19).
Exposure to intense light can bleach rhodopsin-rich night visions cells (known as rods). That results in the cells not responding as well as they should.
The Grass Really is Greener On the Other Side
- Seniors with optimal eye health were demonstrated to have higher lutein levels (20)
- Retinal pigments are also antioxidants and have overall health benefits independent of their benefits to the eye (19, 20, 21, 22)
Macular degeneration is a diagnosis no one wants to hear. The prognosis of macular degeneration is always viewed poorly.
The failure in central vision, those holes that progress at an unexpected rate can make life a long journey of loss anticipation.
Often patients ask heartbreaking questions like: “will I be able to see my grandchildren? Or will I be completely blind by then”.
Visual changes can be harsh realities that seem almost impossible to escape.
Surprisingly there is some evidence that supplementing with pigments like lutins, zeaxanthin and astaxanthin can significantly delay the progression of macular degeneration.
Even more shockingly, there are studies that show an improvement of visual acuity upon a simple increase in the intake of dark leafy greens (19, 20, 21, 22).
Older adults with normal lutein and zeaxanthin levels tend to have the visual acuity of 20 year old's (20).
Important Note: The pigments that are responsible for maintaining the dark velvety backdrop of the eye are functional anti-oxidants which means that they play a role in protecting many other components of vision including cataract prevention, preventing lense clouding, assisting with eye pressure maintenance and helping with optic nerve problems.
Other Natural Eye Health Components Worth Mentioning
Evidence shows that Vitamin C is protective against cataracts (45% protection) (23)
Bioflavonoids increase the strength of eye blood vessels (24)
Optic Nerve Damage & Pituitary Adenomas
- Pituitary Adenomas are Space occupying, hormonally active growths on the pituitary gland (25)
- They may put physical pressure on the optic nerve
- Immune regulators like Black Seed Oil may play a role in regulating hormone levels and immune reactions (26, 27, 28)
- NAC may play a role in preserving healthy optic nerve function (29)
Many conditions may result in direct damage to the optic nerve (25).
An increase in eye pressure due to glaucoma is one of the common reasons behind optic nerve damage.
Other conditions that may result in direct injury to the optic nerve include pituitary adenomas.
Pituitary adenomas are tumors of a gland in the brain that is called the pituitary gland.
Known as the master gland, the gland is responsible for the secretion of many regulating compounds.
Any hormone dysregulation or autoimmune manifestation that disrupts the negative feedback to the gland (sending a” stop secreting” signal) may result in the growth of the gland.
A gland with a tumor the size of a rice grain can put enough pressure on an area known as The Optic Chiasm to cut the flow to the optic nerve.
In such cases, nerve damage as well as blindness can take place (25).
If affected, the horizon gets smaller as peripheral vision is lost due to the pressure on the nerve.
One of the mechanisms for optic nerve damage is high glutamate levels. High glutamate levels overwhelm cells known as the muller cells.
The cells deteriorate and through the bystander effect (being close to a decaying cell that is leaking its damaging contents) surrounding cells are destroyed (26, 27, 28).
If you want to learn more about the effect of NAC on Glutamate metabolism Click Here.
Eye Health in Chinese Medicine
In most eastern traditions, eye health is directly associated with the liver. Overall, the blood-keeping function of the liver is translated as healthy, well lubricated eyes with optimal vision.
Poor flow of Qi (life force energy) results in imbalances that can negatively impact vision.
Pathogens are recognized as environmental factors of imbalance in Chinese medicine and so the eye, like other organs, can be affected by heat, cold, wind, dampness, dryness and wind.
Most of the conditions recognized are ones that are related to sudden impact, lack of lubrication, inflammation and loss of nourishment through blood.
Chinese medicine usually takes on a holistic approach that balances the organs resulting in the imbalance to promote optimal eye health (30).
Natural Health for The Third Eye
- The pineal gland is the structure known as the third eye (31)
- Antioxidants that enhance eye function also enhance pineal function (32)
- Enhanced pineal function means better sleep-wake regulation (32)
- Side benefits include optimal energy levels, better sleep and more dream recall
- Mood and brain optimization are enhanced with better sleep (33)
The gland that common New Age culture refers to as a third eye is anatomically known as the pineal gland.
The pineal gland is a gland of the dorsal diencephalon (location in the brain) and is referred to as a third eye because, despite the fact that it had no direct exposure to light, it contains two classes of photoreceptors: rods and cones (31).
The function of the pineal gland is to maintain healthy rhythmic patterns. It is the structure responsible for signaling the body to sleep when exposed to the dark and to awaken when exposed to light.
The main product of interest in the pineal gland is the hormone melatonin.
The dark hormone, melatonin, is a compound released upon the exposure of the eye to the dark.
Overall, it is a controller of the endogenous circadian clock.
Some studies demonstrate that pineal health directly impacts eye health. For example it was noted that a reduction of oxidative stress at the level of the mitochondria can show a direct benefit for those with glaucoma. Healthy melatonin levels were noted as an important factor (32, 33).
Several studies showed that melatonin and astaxanthin work hand in hand as biomolecules in vitro and in vivo.
Zeaxanthin helps with blue light exposure which maintains healthy melatonin levels
Supplementation which vision-enhancing antioxidant pigments like lutein and zeaxanthin is demonstrated to have a significant effect on sleep disturbances, daytime function and circadian rhythm (32, 33, 34)
How to Choose The Best Eye Support Supplement?
Eye supplements are only as potent as their protective pill casing allows them to be.
As most eye support supplements are made with high amounts of antioxidant pigments, it is important to make sure that the encapsulation method preserves the antioxidant capacity of the formula.
Many eye health supplements are found to be less potent after just months of sitting on the shelf.
The best eye health supplements have the following features:
- Dissolved in oil for best absorbability
- Oil encapsulations also protect anti-oxidants from air and moisture reactability
- A supplement with significant amounts of all 3 major antioxidant pigments
Anyone with a chronic disease that may affect blood vessels (high blood pressure, high blood sugar or high cholesterol) would do best with an eye supplement that contains vascular support like bilberry
Who Needs an Eye Supplement?
- High screen exposure
- Protect eye from light
- Protect sleep-wake cycle
- Age related eye diseases
- Macular degeneration
- High light exposure
- Protect eye from fatigue
- Maintain optimal vision
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