Dry eyes can be extremely uncomfortable. They can turn itchy, red, and swollen. People who have dry eyes often report the sensation of sand in their eyes. They can develop lumps underneath the eyelid and their eyelashes can fall out.
Dry eyes, however, are usually not cause by a lack of fluids to make the tears that lubricate the eye. Dry eyes most commonly result from a lack of lipids the eyes need to make the tears adhere to the surface of the eye. Essential fatty acids from fish oil can help.
The Three Levels of Tears
Tears keep the eyes lubricated. Tears are not just water. They actually come in three layers.
The lowest layer of tears is made of fatty acids. This layer is about a tenth of a micron thick, or about a quarter of a millionth of an inch. This extremely thin layer of fatty acids, however, keeps fluid from rolling off the surface of the eye.
The second layer of tears is made of mostly water. This layer of water and salts is about 70 microns or three ten-thousandths of an inch thick. And the outer layer of tears is a material called mucin. This sticky layer is not even as thick as the lipid layer that helps hold tears to the surface of the eye, but it is essential for keeping the tears from evaporating.
Everybody has times that one or more of the components of tears is produced in excess. Sticky eyes of conjunctivitis and watery eyes of allergies are good examples of excess tear production.
Dry eyes, however, are caused by deficiencies in the production of one of more components of tears. And the most common missing ingredient in the production of tears is the lipid layer.
What Causes Lipid Loss in Tears
Two conditions deplete the lipids the eyes need to make the first layer of tears. They are the form of acne known as rosacea, and a bacterial infection called blepharitis.
In rosacea, the nerves control the Meibomian glands that make the lipid layer of tears are activated by cold, heat, caffeine, or any of the usual triggers for acne outbreaks. They clamp the glands shut so that the lipid layer is not laid down and the top two layers of tears won't stick to the eye.
Blepharitis bacteria attack the lipid layer in a different way. These bacteria produce peroxides as a byproduct of consuming the mucin the eyes use to make the top layer of tears. The peroxides dissolve the lipid layer next to the eye and the bacteria themselves destroy the top layer that keeps the middle layer of watery fluid from drying out. When you have blepharitis, the top and bottom layers of tears are defective so the middle layer simply evaporates or rolls onto your cheeks.
Other Causes of Dry Eyes
While rosacea and blepharitis are the most common causes of dry eyes, depletion of tears also occurs in autoimmune diseases that affect the tear ducts, especially Sjogren's syndrome. Medications that affect the nervous system, especially beta-blockers for high blood pressure, and steroids, such as those used in asthma inhalers, also interfere with tear production. Certain brands of birth control pills and treatments for Parkinson's disease and kidney stones also cause a dry eyes side effect.
Treat Symptoms Before You Take Care of Causes
- A Healthy EyePhoto by Jean-Jacques Milan
If you have dry eyes, you don't want to wait for changes in your nutritional status to stop dry eyes and eye inflammation. You undoubtedly want relief right now! Your first line of treatment will be eye drops to use as artificial tears.
When you are choosing artificial tears, you want to avoid any product that contains preservatives. Chemical preservatives themselves can dry out your eyes, and they can also cause eye allergies.
On the other hand, this means you have to be careful how you apply the product. If you have blepharitis, touching the tip of the artificial tears applicator to your eye can contaminate the artificial tears with blepharitis bacteria. This means you will reinfect yourself every time you use the product to treat your symptoms if you are not careful.
There is a similar problem with makeup. If you use eyeliner, eye shadow, or even any makeup on your nose and cheeks, you must avoid contaminating the container with bacteria from your eyes. It's usually a good idea to avoid any kind of eye makeup altogether for six to eight weeks while controlling the infection. Makeup has to be removed at night to keep it from catching germs in eye secretions released while you are lying down to sleep.
First aid for dry eyes is the application of warm (never hot) moist heat. This is especially useful if you have blepharitis. The slight elevation of temperature will slow down the multiplication of blepharitis bacteria, and the moisture will also help dissolve mucins that interfere with the flow of tears from the tear ducts.
Correcting the Causes of Dry Eyes
Whether your dry eyes are a complication of Sjogren's syndrome, blepharitis, or rosacea or if they are a side effect of medication, nutritional changes usually help. If the problem is Sjogren's syndrome, rosacea, or a medication your doctor cannot change, then you will need ongoing nutritional support indefinitely.
The first nutritional intervention for dry eyes may be mean deleting certain foods from your diet. What you want to do is to limit your consumption of foods that cause the creation of a class of chemicals called "biogenic amines" in your digestive tract. With descriptive names like cadaverine and putrescine, the biogenic amines circulate through the body and cause especially inflammatory reactions in the skin and tear ducts. Reducing your consumption of foods that create biogenic amines can make a noticeable benefit to the natural lubrication of your eyes.
Food that generate biogenic amines include:
- Cured pork, especially baked ham,
- Fermented meats, such as salami,
- Any kind of "stinky cheese," but also Swiss cheese,
- Any kind of "smelly fish," but also tuna.
If it is a protein food, and it has a strong odor, it probably contains high concentrations of biogenic amines. These foods aggravate dry eyes. Avoid them when you can.
The next thing to do is to make sure you are getting enough B vitamins and zinc. The people who are most like to benefit from B vitamin supplements are people who take products for heartburn and gastroesophageal disease. Reducing the acidity of the stomach makes it harder for the body to extract the B vitamins it needs. Zinc requirements are increased when B vitamins are taken. A single "complete B" supplement every day along with at least 15 mg of zinc, preferably zinc gluconate, is enough.
Then it helps to take fish oil, especially if you have rosacea or blepharitis, the conditions that interfere with the production of the lipid layer. How much fish oil for dry eyes? Just 1,000 mg of DHA + EPA a day is enough to make a difference in better vision. You can get that amount of essential fatty acids by taking 2 or 3 capsules of Xtend Life, Nordic Naturals, or New Vitality fish oils, or by taking up to 12 capsules a day of other brands.
Certain other health practices help:
- Maintaining humidity in your home with a vaporizer or humidifier can be very helpful if you live in a dry climate, or if you are using forced air heating during the winter.
- Applying a warm (never hot) moist compress to your eyes a few times a day helps restore moisture temporarily. It's not a substitute for tears, but it can make your eyes feel better.
- Some people have a rosacea-like dryness in the eyes without having full blown rosacea. If this is the case for you, you may avoid dry eyes by cutting back on caffeine, avoiding spicy foods and hot peppers, staying out of the wind whenever possible, and avoiding sudden changes in air temperature.
There are certain symptoms that always require medical attention:
- See your doctor immediately if you develop a red or pink ulcer on your eye.
- See your doctor immediately if you develop a fever that seems to be centered in either or bothy eyes.
- See your doctor immediately if you develop unusually blurry vision that is not relieved by hydrating your eyes.
- See your doctor immediately if contact lenses seem to stick to your eyes.
- See your ophthalmologist for regular eye exams even if your symptoms don't get worse.
If you wear contacts, don't lubricate them with spittle. The microorganisms that cause blepharitis can also live in the mouth.
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