Egg Protein and Egg White Nutritional ValueEggs and egg protein has long been a staple of bodybuilding nutrition and supplementation. Egg protein is commonly referred to as the "perfect protein" - egg proteins are the common reference to which other proteins are compared to.
Two values are commonly used to measure protein quality:
Protein Digestibility Corrected Amino Acid Score (PDCAA) and biological value. Biological value measures the amount of protein retained from the absorbed protein. Egg protein scores 100 on the biological value, meaning all ingested egg protein is retained (used) by the body (egg protein contains all the essential amino acids needed by the body). Another protein which scores 100 on the biological value
score is whey protein.
The PDCAA score measures the "completeness" of a protein, where a score of 1.0 is the highest measure. Egg whites, along with soy protein isolates, whey protein, and casein protein all score 1.0 on this. Whey protein actually scores 1.14 on this, but is reported at the highest 1.0.
Nutrition Value of Eggs, Egg White, & Egg Yolk
An average sized egg (~50g), contains 39g water, 6.5g protein, 5.6g fat, 0.5g carbohydrates, and a host of vitamins and minerals. Egg yolk and egg white make up the egg, and have distinctly different nutrition values.
Egg Yolk Nutrition Fact:*
Large size - 17g
Water - 8.893g
Energy kcal - 54.740
Energy kj - 228.820
Protein - 2.696g
Total lipid (fat) - 4.512g
Cholesterol - 209.78mg
Egg White Nutrition Facts: *
Large size - 33g
Water - 28.898g
Energy kcal - 17.160
Energy kj - 71.280
Protein - 3.597g
Total lipid (fat) - 0.056g
Carbohydrate - 0.241g
** Values taken from the USDA Nutrition Database
As you can see the egg white contains more protein with almost no fat content, and no cholesterol, while the egg yolk has less protein, and all the fat and cholesterol! This has been the major reason why so many people eat egg whites and throw away the egg yolk. "Just think of all the fat and cholesterol", is what most people think.
Well, I should clear up a common misconception. Although egg yolks contain high amount of fat, it has only 1.6g of saturated fat (the bad kind), and the rest is poly and monosaturated fats which are the good fats.
Fat content in eggs - 5.6
Inc saturated - 1.6g
Monounsaturated - 2.4g
Polyunsaturated - 0.6g
Despite what you're taught to believe, a large portion of the fats in egg yolk are good fats! So eating just one yolk a day isn't going to do any harm. obviously for serious lifters who eat several up to dozens of eggs a day, its wise to eat only the egg white and just 1 or 2 egg yolks.
Studies have found that saturated fats is the leading cause of high blood cholesterol levels - even more so than dietary cholesterol (that you get from food).
A Study of Egg Consumption and Risk of Cardiovascular
Disease in Men and Women.
This study involved 37,851 men aged 40 to 75, and 80,082 women aged 34 to 59, to study the association between egg consumption and risk of coronary heart disease. During 8 years of follow for men and 14 years of follow up for women, the researchers documented 2626 total cases of coronary heart disease and stroke in both men and women.
They found no evidence of an overall significant association between egg consumption and risk of coronary heart disease (CHD) in either men or women, and in subgroup analyses, higher egg consumption appeared to be associated with increased risk of CHD only among diabetic subjects.
These findings lead to the conclusion that consumption of up to 1 egg per day is unlikely to have substantial impact on the risk of CHD or stroke.
Source: Journal of american medical assoc.. 1999;281:1387-1394 www.jama.com
A Study on the effect of dietary cholesterol on plasma cholesterol concentration in subjects following reduced fat, high fibre diet.
168 subjects participated in a randomized crossover study to determine whether doubling the present dietary cholesterol from eggs had any influence on blood cholesterol levels.
The participants followed a reduced fat diet with higher ratio of polysaturates to saturate fats. The participants ate either 2 or 7 eggs a week.
After 4 weeks, there was a small increase in total cholesterol of the group eating 7 eggs; however after 8 weeks, this was no longer apparent. This lead to the conclusion that further reduction in dietary cholesterol seem to be unnecessary for those people who already reduced their intake of saturated fats and increased the ratio of polyunsaturated to saturated fats.
So what does this all mean? Simple. You don't have to worry all that much about eating just 1 whole egg each day - its unlikely to increase your risk of coronary heart disease or stroke.
So eat up!
For those who love eggs and eat dozens a day, just eat one yolk and the rest egg whites. And if you're looking for a simpler solution to cooking eggs everyday, then you're probably looking for egg protein supplements.
Rob's Note: I am pretty sure that based on what I'm learning about eggs,
I'm going to switch my morning 2 yolk, 6 whites ommellet to a blended drink from now on. I'm going to skip the cooking of the eggs and eat them raw, blended, and then have a breakfast burrito to get my whole grain tortilla, salsa, and beans in there. Hmmm... sounds nummy just thinking about it. My philosophy has always been to try things for 6 months at least, then change it up to see the effects. "Constant and neverending improvement". Ack... the thought of cleaning a blender every day sucks though.