The health of our eyes, as well as our vision, depends on the proper structure of the parts of the eye as these parts are the key for the transmission of visual information. These structures, in turn, are highly dependent on nutrition. As we will see, the omega 3 benefits for the eyes cannot be ignored in our diet as they play a central role in keeping our vision in good order.
Taking into account that a large part of the diseases that affect our organism are caused by a defective nutrition, either too much or too little, the correct knowledge of our nutritional needs is essential nowadays. Because of the many choices available to us in the supermarket, it becomes imperative to be aware of the foods we eat since they can prevent or delay the appearance of diseases.
In this particular case that concerns us today, our eye health and vision, Omega-3 fatty acids and olive oil are essential components and should be omnipresent in our diet. Why? Because DHA is the omega 3 fat more abundant in the brain (97%) and in the retina (93%) of mammals.
Omega 3 benefits in the eye area
Numerous studies have shown beneficial effects of the fatty acids omega-3 both in healthy individuals and those with chronic illnesses on certain cardiovascular and immune functions. Within the omega-3, DHA is also an important component of cell membranes, especially in the brain (97%) of the total polyunsaturated fatty acids and in the retina (93%), which makes it essential for their proper functioning and development.
Thus, in the visual organ, DHA participates in development and vision in general and in the retina function in particular. It is an important component of the structure of the retina, participating in its normal development and helping to keep the function and visual health. A deficiency of Omega 3 fatty acids in the retina is associated with low visual capacity because such deficiency affects the permeability, fluidity and thickness of the membrane which in turn affects the transmission of images.
In addition, DHA plays an important role in the normal development of the pigmented epithelium of the retina, protecting it from oxidative damage. DHA has also a protective effect against the neuro-degeneration of the eye.
As you see, omega 3 fatty acids, especially DHA, play a substantial role in visual development. If our eyes lack Omega 3 fats, their structures will be defective and the foto-transmission will not go through.
Three Families of Omega fatty Acids
Within the Omega fatty acid family we find 3 different types. The difference is due to their chemical structure.
- Omega-9 fatty acids: The Omega-9 fatty acids, such as the oleic acid present in olive oil, are not essential. Essential in this case means that our bodies have enzymes that can fabricate these fatty acids although they may not be in sufficient quantities.
- Omega 6 fatty acids: These fatty acids are said to be essential because our body cannot manufacture them. It is therefore necessary to introduce them in adequate amounts from the diet.
- Omega 3 fatty acids: These fatty acids include ALA, DHA and EPA. DHA is part of cell membranes and contribute to its permeability and elasticity. Its role is relevant in keeping a healthy immune system, coagulation, and an adequate blood pressure.
Omega 6 and Omega 3 fatty acids
Fat shows up in the membranes of our body cells shortly after we eat it. Although fatty acids have many variations, the two main categories in the manufacture of eicosanoids, very potent substances similar to hormones, are fatty acids omega 3, found in marine life and some terrestrial plants, and fatty acids omega 6, found in vegetables such as corn, sunflower seeds and in the flesh of animals fed with foods of terrestrial origin.
When you eat a piece of meat or you use corn oil in your cooking, the omega 6 fatty acids derived from cultivated plants tend to become a substance called arachidonic acid which in turn generates highly inflammatory substances that increase the thickness of the blood and the narrowing of blood vessels, two conditions that affect the eyes as well as the heart.
The fat in foods of marine origin is quite different and more benign. Omega-3 fatty acids tend to transform themselves into substances that counteract platelet stickiness, dilate the blood vessels, and reduce the inflammation and cellular damage.
The predominance of one of the two fats will determine health or disease. If your cells are flooded with fatty acids omega 6, this excess will lead to disease. If you have enough fatty acids omega 3, these may control or reduce the risk of illness.
Food sources of DHA Omega-3 fatty acids
DHA is not present in foods of terrestrial origin. Omega-3 fats mainly come from a certain type of algae called phytoplankton, found in marine waters. Fish eat these algae which in turn are transferred to us through the food chain. DHA and EPA are mainly in fatty fish such as tuna, anchovies, mackerel, salmon, herring, sardines, etc., in fish oil, in seafood, liver, and in small amounts in some birds and egg yolks.
The acid α-linolenic (ALA) is present in dark green leafy vegetables, soybeans, flax, canola, nuts, and red fruit plants. Our body has the ability to convert ALA into EPA and DHA. However, not all individuals can convert ALA into DHA. It has been shown that only about 0.1% of ALA turns into DHA. Diseases such as diabetes make it harder for the body to convert ALA into DHA. For this reason, an adequate amount of DHA has to be supplemented from our diet.
Current consumption trends for Omega-3
For many years, the excessive intake of saturated fatty acids has been connected with cardiovascular disease. Lately, scientific research has gone one step further and is studying the relationship between the Omega 6 and Omega 3 fatty acids; a proper balance between these fatty acids plays a determinant role in human health.
We need to understand that it has been a very important change in the type of fat humans ingest nowadays. For thousands of years, fat intake was low and it was largely based on the consumption of fish, vegetables, and hunting (animals rich in omegas-3s). In the last decades, however, most fats in our diet come from dairy and farm animals fed with grains while our genetic information has not suffered large variations.
Our genetic body constitution is adapted to the diet of the hunter/gatherer man of 40,000 years ago and the change has been too sharp to be accepted yet by our metabolism. Thus, the number of cardiovascular diseases, diabetes, autoimmune diseases, and other related inflammation diseases has gone up.
Western diets have changed the balance of fatty acids omega-6/omega-3 with respect to what humans have been eating over hundreds of thousands of years. It is worth it to mention that Greek diet has a proportion of 1.5:1 omega-6/omega-3. Japan 4: 1; the United States current diet has a ratio of 16: 1; and the United Kingdom and Northern Europe a ratio of 15: 1. The Cretans (Mediterranean diet) that are closer to the original diet get omega 3 fats mainly from fish, wild plants, hunting, eggs and olive oil.
Grass fed beef has an omega-6/omega-3 ratio of about 2. 5: 1, however, if beef is fed with grains, the ratio can reach 20:1.
How to restore the balance between omega 6 and omega 3
To prevent inflammation, thick blood, and to have cell membranes more flexible, all conditions that have an impact in our eyes and vision, we need to go back to a healthy balance between omega 6/omega 3 fat. The way to do it is as follow:
- Eat more fatty fish such as sardines, tuna, salmon, mackerel, etc. 2 or 3 times a week. Check the safety of fish.
- Include in your diet dark green leafy vegetables. A glass of homemade vegetable juice is an ideal solution to include this type of greens. I drink this type of juice at least 4 or 5 times a week.
- Use only extra virgin olive oil in your salads and your cooking. In my next article I’ll talk about the benefits of olive oil for the eyes.
- Stay away from corn and sunflower oils when cooking.
- Buy meat and eggs from animals fed with grass (free range) instead from animals fed with grains.
Unless we get back to a balance between omega 6/omega 3 fatty acids, we will not enjoy the omega 3 benefits. This means that among other health problems, our eyes will deteriorate at a higher speed than usual. If you are diabetic remember you have a greater risk of eye deterioration than people without diabetes because of the disease.