Eggs by Design
Scientists, farmers, and food manufacturers have found ways to change the nutrient composition of eggs. Are these new-fangled eggs better for you than regular eggs?
A quick glance at the egg section of most large supermarkets gives consumers several choices. In addition to the standard white and brown eggs, you can buy eggs that are cage-free or organic. Plus, you can choose ones that have increased levels of omega-3 fatty acids. You can also choose from a variety of egg-substitute products, most of which are refrigerated or frozen and packaged for easy use.
Eating Eggs Again
Consumers are buying eggs in record numbers—a far cry from egg consumption during the 1980s, when consumers were taught to avoid eggs and, in particular, egg yolks. There are three reasons for this recent surge in popularity. The first is current research indicating that moderate egg consumption can be part of a healthful, low-fat eating plan. The second reason is that we are eating more processed foods, which require eggs. And third is the popularity of both high-protein and vegetarian-based diets.
Understanding Nature's Design
The standard egg is an economical source of nutrition. Eggs contain many essential vitamin and mineral needed by humans, including zinc, iron, folate, vitamins A, E, and B complex—all this for only 70 calories! Egg protein is of such high quality that it is the standard reference for comparing the protein content of other foods. Current nutrient analyses suggest that the cholesterol content of an average egg is about 213-220 mg, rather than the previously estimated 274 mg. All of this cholesterol is contained in the yolk part of the egg. The American Heart Association (AHA) continues to recommend that people limit their cholesterol intake to 300 mg per day
Nature delivers eggs in two colors—white and brown. Contrary to popular thinking, brown eggs are neither organic nor different in nutrition from white eggs. The breed of the hen determines the shell color. Breeds with white feathers and ear lobes lay white eggs. Hens with red feathers and ear lobes lay brown eggs.
Learning About Cage-free, Range-free, and Organic Eggs
Hens are typically caged in modern facilities with controlled temperatures, humidity, light, and air circulation. American birds are fed hormone-free, high-quality feed with automatic feeders. Fresh water is provided through self-cleaning cups and valves.
Because some consumers are opposed to this type of confinement, options such as cage-free and range-free eggs are available. These types of eggs have the same nutrient composition as the standard egg.
Getting the Scoop on Designer Eggs
During the past several years, scientists and egg producers have joined together to produce specialty or so-called "designer eggs." According to the Egg Nutrition Center, an industry research group, these specialty eggs account for a growing percentage of market sales.
One such egg is the high omega-3 egg. Hens are fed a special oil that accumulates in the egg yolk, increasing the omega 3-fatty acids, while decreasing the saturated fat. Retail omega-3 fatty acid eggs contain three to four times the content of the standard egg. As a bonus, these eggs also have higher amounts of vitamin E.
Some scientists and nutritionists see these designer eggs as a realistic way to help Americans eat more omega-3 fatty acids, which have been shown in some studies to reduce the risk of heart disease. In fact, one egg fortified with this fatty acid provides the same content as a one-ounce serving of oily fish, such as salmon.
Egg substitutes are another type of specialty egg. These liquid egg products are cholesterol-free, because they're made from only egg whites. The yolk is typically replaced with other ingredients, such as vegetable oil, emulsifiers, stabilizers, gums, and artificial colors, and then the product is fortified with vitamins and minerals. Egg substitutes have the added advantage of being pasteurized. This means you can use them safely in recipes that traditionally call for raw eggs, such as mayonnaise, salad dressings, eggnog, and pastry filling, without being concerned about Salmonella contamination, which can result from undercooked eggs. Another option for lower-cholesterol egg is to use two egg whites, or one egg white plus two teaspoons of unsaturated oil, to replace a whole egg in cooking.
American Egg Board
Egg Nutrition Center
Alberta Egg Producers
Egg industry facts. American Egg Board. Available at: http://www.aeb.org/Retailers/industry.html. Accessed October 17, 2007.
Egg nutrition facts. American Egg Board website. Available at: http://www.aeb.org/retailers/egg-nutrition-facts. Accessed May 12, 2011.
How do I follow a healthy diet? American Heart Association website. Available at: http://www.heart.o.... Updated March 2011. Accessed May 12, 2011.
Hu FB, Stampfer MJ, Rimm EB, et al. A prospective study of egg consumption and risk of cardiovascular disease in men and women. JAMA. 1999;28:1387-1394.
Specialty eggs. Egg Nutrition Center. Available at: http://www.eggnutr.... Accessed May 12, 2011.
United States Department of Agriculture and United States Department of Health and Human Services. Dietary Guidelines for Americans, 2010. 7th Edition, Washington, DC: United States Government Printing Office, December 2010.
Last reviewed May 2011 by Brian Randall, MD