Brown vs. White Eggs: Nutrition, Genetics & Shell Color

Genetics determine the shell color of a chicken egg. Eggs sold in the U.S. are predominantly white, but chickens lay eggs in other colors, depending on the breed. There is no strong evidence that a brown egg is nutritionally different than a white egg.

Composition

• Eggshells are mostly composed of calcium carbonate, a mineral needed in animal and plant life to form skeletons and shells.

Process

• Hens secrete a pigment that covers an egg̵7;s outer layer. Brown eggshells utilize the pigment protoporphyrin. White eggshells have no pigment.

Determination

• Chicken breeds that produce brown eggs include New Hampshire, Wyandotte and Australorp. White eggs are produced by breeds that include Leghorn, Sebright and Chabo.

Considerations

• Brown eggs tend to be more expensive than white because the breeds that produce brown eggs are generally larger and thus require more food.

Warnings

• Whether the egg is brown or white, salmonella bacteria can reside on the egg̵7;s shell. All eggs produced for consumers are washed and sanitized before packing. It̵7;s rare that an eggshell is contaminated once it is available for purchase, but it is wise to select eggs that are clean.