Once a bird lays an egg, it need only keep that egg warm for a certain period for a chick to hatch. This empirical phenomenon has been taking place ever since the first birds appeared on earth.

The embryos of birds, unlike those of mammals, develop in eggs outside their mothers' bodies, where sanitary conditions, changing air temperature, and variable humidity are anything but optimal for survival. Yet as long as the egg is kept at a suitable temperature, the embryo will survive this hostile environment and emerge from the egg as a newborn chick.

Unlike human beings, bird embryos develop without the aid of an umbilical cord supplying nutrients from the mother's body. Instead, the egg functions as an incubator equipped with everything needed to sustain the growing embryo until it hatches. In this process, the eggshell membrane plays a crucial role. Adhering tightly to the inner surface of the shell, this extremely thin lining (0.07 mm) gently envelops the embryo and protects it from harmful microorganisms. It has been revealed that the eggshell membrane is also involved in the growth and differentiation of the chick's 10 billion cells as well as maintenance of life functions during incubation.

The main component of eggshell membrane is protein fibers made up of more than 20 different amino acids. In fact, the amino acid composition of this unique natural substance is quite close to that of human skin and other human tissues. In addition, it contains both collagen and hyaluronic acid.

What this means is that eggshell membrane holds limitless possibilities for contributing to human health. Today scientists at the University of Tokyo and other institutions are engaged in wide-ranging research aimed at establishing new benefits and uses of eggshell membrane.