MadSci Network: Agricultural Sciences

Re: Do Brown chicken eggs have more cholesterol than white eggs?

Date: Tue Dec 5 16:28:37 2000
Posted By: Dian Dooley, , Associate Professor, Food Science and Human Nutrition, University of Hawaii at Manoa
Area of science: Agricultural Sciences
ID: 973790901.Ag

Aloha, Michelle,

     Regarding your question about white/brown eggs.  Chickens 
characteristically lay either white OR brown eggs (or even some other 
color, like green).  This is pretty much due to the genetics of the breed 
of chicken, although I imagine that diet can have a minor effect on the 
color of the shell. So white chickens generally lay white eggs, whether 
they are on the farm or in mass-production facilities.  Brown chickens 
(like Rhode Island Reds) lay brown-shelled eggs...these may be what you 
think of as 'farm chickens.' 
     As to the cholesterol content of the egg, I guess the best way to 
state the answer is that a chicken egg is a chicken egg is a chicken egg.  
The cholesterol is found in the yolk;  cholesterol is a fat-like compound 
that they human body can make easily, so there is no official 
recommendation for a minimum intake in your diet.  The average egg yolk 
contains about 220 mg;  there is never any differentiation in nutrient 
tables as to white vs. brown eggs...or any other color shell, for that 
matter.  The difference that you might have noticed in the color of the egg 
yolk is due to other compounds, not to cholesterol;  and, the color is 
partially due to the diet that the chicken has been eating.  Vitamin A-like 
compounds (carotenes) may impart more yellow to the yolk.  These compounds 
are found throughout the plant kingdom...and chickens, especially 
free-range/farm chickens would have more access to these plants (like 
dandelions?).  Egg producers sometimes add these compounds to the 
food formulated and fed to 'factory chickens' to make the yolks more 
yellow, too. 
    Some nutritionists seem to think that cholesterol in food is a problem, 
so you will see some recommendations to keep the cholesterol level in your 
diet to about 300 mg/day (about the amount 1.5 egg yolks...a yolk contains 
about 220 mg).  However, since your body makes the stuff, limiting or 
restricting cholesterol in your diet (eggs, butter, meats) will only 
upregulate your body's production to some genetically preset level, for 
most people.  The cholesterol level that doctors measure when you have a 
cholesterol screening done is the cholesterol in lipoproteins, which are in 
your blood.  This has little relationship to the cholesterol that you have 
eaten.  Actually, this cholesterol (in lipoproteins) is more affected by 
quantity and quality of fat in your diet, your level of exercise, genetics, 
and a few other factors...not so much by dietary cholesterol.  This is an 
unfortunate and pervasive bit of misinformation that I'd like to see 
cleared up for the public.
     One last bit of egg-trivia:  a duck egg, which is somewhat bigger than 
a chicken egg (70 g, as compared to 50 g) has 620 mg cholesterol/yolk;  a 
goose egg (144 g) has 1227 mg cholesterol/yolk !!...and a quail egg (9 g) 
has 76 mg cholesterol/yolk.  So can you figure out which of the four has 
the most cholesterol/g egg?  Enjoy!

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