Arguably one of the most valuable of our five senses, eye sight is not something to be taken lightly; quick quiz: can you name all the five senses? But, what do you really know about eye health? As always this blog is to educate and spark interest by scratching the surface of eye health, and is no way an attempt to diagnose or treat eye pathology.
Lets start with some basic understanding
- Pupil – the center dark area of the visible eye, is the opening in the iris that allows light to enter the eye, our pupils can change shape according to the amount of light available
- Iris – is the color part of your eye and while the pupil is a hole in the iris
- Cornea – is a transparent outer layer of connective tissue covering the iris and pupil
- Sclera – is tough skin that makes up the “white” part of your eye
- Retina – is the inside area of the eye which contains rod cells (which allows us to see black and white) and cone cells (which allows us to see color); these cells then send signals by the way of the optic nerve to your brain for interpretation as sight
- Optic nerve – is cranial nerve number 2, which is responsible for carrying messages from the eye to the brain
- Blind spot or optic disc – is the spot where the optic nerve attaches to the retina and therefore contains no rods or cones for sight
- Lens – behind the iris and pupil which helps focus light on the retina
- Macula – is where the majority of light hits the retina
- Vitreous humor – is a clear gel inside the eye behind the lens
- Aqueous humor – is a clear liquid between the lens and the cornea
Light passes through the cornea, then the pupil, the lens then focuses the image upside down on the retina, and finally the optic nerve sends the message to your brain to interpret.
Most common eye pathology
- Age related macular degeneration (ARMD)- is a leading cause of blindness in the over 50 year old population. Approximately 60 million have ARMD with approximately 20,000 new cases of ARMD causing blindness per year. ARMD is not fully understood but UV light (free radicals) causing oxidative damage to the retina seems to be a big factor.
- Cataracts- are a white opaque lesion that forms on the lens, there are approximately 3 million cataract surgeries every year, and it is estimated that 20 million people have cataracts. Cataracts can progress to blindness.
- Diabetic retinopathy- effects, to some extent, about 45% of the nearly 81 million Americans that are pre diabetic and diabetic; due to the fact that high levels of sugar in the blood will damage blood vessels, causing your body to replace the damaged blood vessels with new ones. Diabetic retinopathy can progress to blindness.
Actions that can be taken to prevent eye pathology
- Stop smoking
- Blink for hydration (we typically blink less frequently while using computers)
- Take breaks during eye straining activities about every 20 min (such as reading or using computers)
- Get and keep your blood pressure under control (high blood pressure can damage the small vessels in the eye)
- Control blood sugar with diet and exercise (too much sugar in the blood can damage blood vessels and have a negative effect on the lens of the eye)
- Healthy nutrition – Take supplements of anti-oxidants to limit free radical damage. Eat vegetables high in carotenoids ( carotenoids is what gives our natural food its color) lutein (which is in spinach, kale, carrots, and squash, but the best source is from the yolk of eggs) and zeaxanthin (found in peppers, kiwi, grapes, oranges, squash). Eat omega 3 rich foods; like cold water fish. Black currant and bilberry/huckleberries have anthocyanins which helps us have a healthy aqueous humor and intraocular pressure. Astaxanthin has recently been gaining popularity in research which is the carotenoid that gives salmon/lobster/krill/crab their pink or reddish colors; which is why some suggest taking krill oil supplements.
- Sleep deprivation can have a negative effect on eye health due to the rest and replenishment that occurs as we sleep
- Use contact lens’ appropriately, give your eyes a break and wear glasses, clean them, do not sleep with them in
- Wear UV blocking sunglasses
- Wear a hat to shade your eyes
- Never share eye makeup, clean eye make up applicators, do not put eye makeup in your eye or past the eye lash line, remove eye make up before bed
- Understand that looking at screens can strain the eyes and that screen time should be limited when ever possible, for those who wear corrective lenses consider having a pair of “computer only” glasses for reading as sometimes progressive lenses can cause head tilt and neck pain
The bottom line
The American Academy of Ophthalmology stated that people with ARMD may be able to slow the progression of the disease by taking a nutrient supplement containing the following: Vitamin C (500 mg), Vitamin E (400 IU), Beta-carotene (15 mg), Zinc oxide (80 mg), Copper oxide (2 mg).
This recommendation is the result of government research carried out by The National Eye Institute (NEI), a part of the National Institute on Health (NIH). The take home message of eye health, and the common theme, is that there are things that are out of your control (unfortunate accidents/genetics/etc), but more empowering is all that is in your control. We have knowledge that shows us that by following some simple lifestyle practices, and healthy eating we can greatly increase our odds of maintaining great vision throughout our life. Isn’t that amazing…..the odds are ours for the taking.