Demystifier

Eggs may be a staple, but they're not basic anymore. The variety of specialty eggs on the market can be baffling. So can the claims: less fat, more vitamins, more humane treatment of chickens. These select (and costly) yolks make up 5% of eggs consumed in the U.S. but are a growing business. They all tend to taste the same, so what are the differences?

ALL-NATURAL Hens are fed a diet free of additives, fillers and antibiotics. Look for the U.S.D.A. shield for assurance that this claim and others like it are valid.

FREE RANGE Hens are raised outdoors or with outdoor "access." But hens can't survive all seasons, and "access" varies widely.

CAGE FREE Birds are raised in a typical henhouse, though not confined to the normal 56-sq.-in. of cage space. Smaller cages are more sanitary, however, so cage-free hens have a higher mortality rate.

ORGANIC Hens live cage free and eat organic feed. Eggs cost $3-$4 a dozen.

NUTRITIONALLY ENHANCED Eggs' levels of omega-3 fatty acids or vitamin E are raised by adjusting feed. Next: eggs with boosted lutein, which may help ward off blindness.

VEGETARIAN Hens' feed has no animal by-products. Their eggs' nutrient content stays the same.