Egg yolks are indeed full of cholesterol. And, are also loaded with important nutrients, especially the fat-soluble vitamins and essential fatty acids. In fact, it is said that the contents and quantity of those in an egg yolk is so comprehensive that a few- a day, would offer better insurance than a multi-vitamin.
This is why
The yolk of the egg contains most of the nutrients of the egg. Egg whites, contain far fewer nutrients. The only thing that could justify their consumption is their attachment to their companion yolk.
Below is a Chart that compares the nutritional value of egg whites and yolks, with data provided by the USDA.
The yolk contains 100% of-
- Essential fatty acids
- Vitamins A, E, D, and K
More than 90% of-
And, 89% of-
The egg- yolk contains these too, between 50% and 80% of
It should also be kept in mind that the yolk of an egg is smaller than the white. Where the white contains a slim majority of nutrients, such as protein, this is not due to a greater concentration in the white, but simply to the fact that there is more white in the egg than yolk.
😦 The white does not contain 100% of any nutrient 😦
Contains over 80% of the
and also between 50% and 80% of
According to the Executive Summary of the Third Report on Nutrition Monitoring in the United States by the Interagency Board for Nutrition Monitoring and Related Research of the Federation of American Societies for Experimental Biology’s Life Sciences Research Office, the following is true:
- Most groups have a deficient median intake of Magnesium.
- Several groups have a deficient median intake of Calcium.
- Children aged 1-2 and most groups of females, have a deficient median intake of iron.
- All age groups and races have a deficient median intake of vitamins A, E, B6, and Copper.
Considering this information, the importance of the egg yolk and relative unimportance of the egg white becomes even clearer. The yolk contains the majority of the copper, nearly all of the calcium, iron, folate, and B6, and 100% of the vitamins A and E.
The white, on the other hand, is only useful as an added source of magnesium, or if the diet is on the whole deficient in protein. The simple addition of an adequate amount of meat in the diet would provide for both.
Eggs are an excellent source of carotenoids. These are primarily highly absorbable forms of lutein and its partner zeaxanthin. These carotenoids accumulate in the back of the eye and appear to protect against age-related macular degeneration. There is no RDA for them, as researchers are still trying to understand their importance. All of the lutein and zeaxanthin in an egg is contained in the yolk.
Egg Yolks Contain Essential Fatty Acids DHA and Arachidonic Acid
One important set of nutrients that should not be overlooked is the long-chain essential fatty acids. Egg yolks contain the long-chain omega-3 fatty acid DHA, which is necessary for the brain and proper retinal function in the eye, and the long-chain omega-6 fatty acid arachidonic acid, which is required for the healthy skin, hair, libido, reproduction, growth and response to injury. These fatty acids are primarily needed by young children, pregnant and lactating women, and people with degenerative diseases involving oxidative stress, especially those of the nervous system such as Alzheimer’s. While fatty fish and cod liver oil supply DHA in larger amounts, egg yolks have an advantage over these foods because they also contain arachidonic acid and because they do not contain EPA, which interferes with arachidonic acid metabolism.
According to NutritionData.Com, one egg yolk contains 75 mg of arachidonic acid (AA), 20 mg of DHA, but no EPA.
Animal foods from animals raised on pasture are likely much richer in DHA. In all eggs, both the DHA and AA are contained in the yolk.
The Benefits of Raw Egg Yolks
Many people believe that the health benefits of egg yolks are greater when the yolks are consumed raw. Heat destroys enzymes, reduces the amounts of certain nutrients, and may make the amino acid cysteine less available, which is needed to synthesize the master antioxidant of the cell, glutathione.
Those who eat raw egg yolks report easier digestion, increased stamina, and resistance to illness (I stamp that); however, there is a little evidence to support the common belief that consuming raw egg yolks is dangerous (also).
Please see Dr. Mercola’s article on the safety of eating raw egg yolks if you are concerned about this.