Many people have a preference when it comes to egg color.
Some people believe brown eggs are healthier or more natural, while others feel that white eggs are cleaner or simply taste better.
But are the differences between brown and white eggs more than shell-deep?
This article explores whether one type of egg is truly healthier or tastier.
Chicken eggs can come in different colors, and it's common to find both brown and white eggs in the supermarket.
However, many people don't know what causes eggs to have different colors.
The answer is quite simple — egg color depends on the breed of the chicken. For example, White Leghorn chickens lay white-shelled eggs, while Plymouth Rocks and Rhode Island Reds lay brown-shelled eggs (, ).
Some breeds of chicken, such as the Araucana, Ameraucana, Dongxiang and Lushi, even lay blue or blue-green eggs ().
The different eggshell colors come from pigments the hens produce. The main pigment in brown eggshells is called protoporphyrin IX. It is made from heme, the compound that gives blood its red color ().
The main pigment found in blue eggshells is called biliverdin, which also comes from heme. It’s the same pigment that sometimes gives bruises a blue-green color (, ).
But while genetics is the main factor that determines egg color, other factors can have an influence too ().
For example, as hens that lay brown eggs age, they tend to lay larger and lighter-colored eggs.
The hen's environment, diet and level of stress may also affect shell color, to some extent ().
These factors can make the shade lighter or darker, but not necessarily change the color itself. The main factor determining color is still the breed.
Summary: Chicken eggs can be brown, white or even blue-green. The color of an egg is determined by the breed of the hen that lays it.
Often, people who prefer brown eggs do so because they believe brown eggs are more natural and healthy than white eggs.
However, scientists have compared eggs with brown shells to those with white shells to see if there is any difference. Several studies have found that shell color has no significant effect on egg quality and composition ().
This means that the color of an egg's shell doesn't have much to do with how healthy it is. The only real difference is the pigment in the shell.
However, there are other factors that can affect the nutritional content of an egg.
The hen's environment can have a major impact. For example, eggs from hens that are allowed to roam in the sunshine contain 3–4 times the amount of vitamin D you'd find in eggs from a conventionally raised hen ().
The type of feed a hen eats can also affect the nutrient content of her eggs.
Hens fed a diet rich in omega-3 fatty acids produce eggs that contain much higher levels of omega-3 fatty acids than normal. The same effect has been found with vitamin D when chickens eat vitamin-D-enriched feed (, ).
Summary: There is no nutritional difference between brown and white eggs. However, a hen's diet and environment can affect an egg's nutrition.
Some people swear that brown eggs taste better, while others prefer the taste of white eggs.
But just as with nutritional content, there is no real difference between the taste of brown- and white-shelled eggs (13).
However, that doesn't necessarily mean that all eggs taste the same.
Even though shell color doesn't make a difference, other factors such as type of feed, freshness and how an egg is cooked may affect the way it tastes.
For example, hens fed a diet rich in fat produce more flavorful eggs than hens fed a lower-fat diet. And hens given feed that contains too much fish oil, certain types of fats or even vitamins A or D may produce fishy or off-tasting eggs (13, 14, ).
The diet of a home-raised hen is not the same as that of a conventionally raised hen, which may also affect the flavor of the eggs.
Additionally, the longer the egg is stored, the more likely it is to develop an off flavor. Storing eggs at a stable, low temperature, like in the refrigerator, can help preserve their flavor for longer (13).
These reasons may be why some people believe that eggs from home-raised chickens taste better than those from conventionally raised chickens.
Backyard eggs don't go through processing and shipping like conventional ones do, so they may end up on your plate more quickly than eggs bought from the store. Because they're fresher, they may taste better.
Surprisingly, the way an egg is cooked may affect its flavor too.
One study looked at how fish oil, which is used in chicken feed to raise omega-3 levels, changed the flavor of eggs. It found that fish-oil and conventional eggs tasted the same when scrambled (16).
However, when boiled, the eggs from hens fed fish oil had more of an off-flavor or sulfur-flavor (16).
So, while many factors may affect egg flavor, shell color does not.
Summary: Brown and white eggs generally taste the same. But eggs can taste different depending on how fresh they are, the way they're cooked and the diet of the hen.
Even though brown and white eggs seem to be the same by all measures other than color, brown eggs still tend to cost more at the store.
This fact has led many people to believe that brown eggs are healthier or higher-quality than white ones.
However, the cause of this price gap is quite different.
In truth, brown eggs cost more because in the past, brown-laying hens tended to be larger and lay fewer eggs than white-laying hens. Therefore, brown eggs needed to be sold at a higher price to make up for the extra costs ().
Today, brown-laying hens have nearly the same production costs as white-laying hens. Nevertheless, their eggs still tend to come with a higher price tag ().
This may be because specialty eggs, such as free-range or organic, tend to be brown rather than white.
Summary: Brown eggs used to cost more because brown-laying hens produced less and weighed more. While that's no longer true, brown eggs still come with a higher price tag.
It's clear that color isn't an important factor. So what should you take into account when buying eggs?
Here's a quick look at the different types available and what their labels mean.
The term "natural" is not regulated in the US because natural cannot be defined (17).
Eggs labeled "naturally raised" or "all natural" are no different than any other egg.
Eggs that are certified as organic in the United States and European Union are from chickens given only organic and non-GMO feed.
They must also have year-round access to the outdoors.
In addition, they have not been given antibiotics or hormones, though hormones are never permitted for laying hens (18).
The organic label means antibiotics may only be used when medically necessary. Otherwise, low doses of antibiotics are often given in feed and water, which can contribute to antibiotic resistance in bacteria.
Currently, there is no evidence that organic eggs are more nutritious than conventional eggs ().
Still, certified organic hens' quality of life is probably better and greater access to sunshine probably increases the vitamin D in their eggs ().
When the term "cage-free" is applied to eggs, it may be misleading.
While conventionally raised hens in the US are housed indoors in very small, individual cages, cage-free hens are housed in an open building or room (17).
However, the conditions for cage-free hens are often still very crowded, with no access to the outdoors.
Cage-free living may be slightly better for the hen. However, in terms of nutrition, cage-free eggs are probably no healthier than conventional eggs.
The label "free-range" signifies eggs that come from hens housed with some form of continuous access to the outdoors (17).
This ideally provides a better quality of life for the hens.
It may also increase the nutritional quality of the eggs, since hens that are exposed to sunlight produce eggs with much higher vitamin D levels ().
Omega-3 enriched eggs come from hens fed a diet enriched with healthy omega-3 fats.
Therefore, the omega-3 content of the egg is much higher than normal.
Omega-3 enriched eggs provide an alternative source of omega-3 fats, which are traditionally very limited in the human diet. Choosing omega-3 enriched eggs may offer some health benefits.
Previously, one small study showed that consuming four omega-3-enriched eggs every day for four weeks lowered blood triglycerides and blood pressure in participants ().
Another study found that consuming two omega-3 enriched eggs every day for six weeks increased the omega-3 fat content of the breast milk from breastfeeding mothers ().
Overall, omega-3 enriched eggs may offer some additional health benefits over the average egg.
Backyard and Local
Eggs that come from backyard flocks or those bought directly from small, local farmers are likely to be the freshest and usually come from hens that live in more natural environments with plenty of access to sunshine.
The diets of backyard hens may be different from conventionally raised hens and this may affect the nutrition content of the eggs, as well.
This is especially true if the hens have access to grass, since hens fed grass as well as conventional feed have been found to produce eggs that have higher levels of omega-3 fats and vitamin E (22).
However, backyard flocks are not subjected to the same hygiene regulations as commercial flocks, so be sure to buy local or backyard eggs only from sources that you know follow good care and hygiene practices.
Summary: The color of an egg isn't important, but there are many other factors to consider when selecting eggs.
Eggs come in many colors, depending on chicken breed.
However, there is no nutritional difference between brown and white eggs. In the end, the only real difference is shell color and maybe price.
Nevertheless, other factors do affect the flavor and nutrition of eggs, including the hen's diet and housing conditions.
So the next time you reach for a carton of eggs, make sure you're taking these other factors into account. Shell color won't tell you the whole story.