Healing Powers of Swallow Birds Nest Remain Mysterious

Made from the saliva of cave-dwelling birds called swiftlets, the nests are dangerous to harvest, laborious to prepare and have, according to traditional Chinese medicine, a long list of health benefits.

Traditionally consumed in soup, Swallow Birds Nest are now being turned into food and drink additives as well as put into cosmetics, say two Chinese researchers who have assessed just what is known about the nutritional and medicinal properties of this expensive, and to Westerners, strange-sounding health food.

Science cannot yet explain the healing powers attributed to the soup, they conclude. Swallow Birds Nest "bioactivities and medicinal value are still open to question as there (is) not much scientific research on the medicinal properties," Fucui Ma and Daicheng Liu of Shandong Normal University in China write in a review article to be published in the October issue of the journal Food Research International. .

Swiftlets live in limestone caves around the Indian Ocean, in South and South East Asia, North Australia and the Pacific Islands. Males primarily build the nests, attaching them to the vertical walls of the caves. Removing them can be dangerous and painstaking work, and, depending on the type of nest, it can take one person eight hours to clean 10 nests, the researchers write. [Amazing Caves: Photos of Earth's Innards]

For possibly 1,200 years, the Chinese have prepared and eaten the nests as a soup. The nests are considered to have a high nutritional and medicinal value, believed to have everything from anti-aging and anti-cancer properties to the ability to improve concentration and raise libido.

Protein is the most abundant constituent of the nests, which contain all of the essential amino acids, the building blocks out of which proteins are made. They also contain six hormones, including testosterone and estradiol, the researchers write.

The nests also contain carbohydrates, ash and a small quantity of lipids (naturally occurring molecules that include fats). Previous research has indicated that the nests contain substances that can stimulate cell division and growth, enhance tissue growth and regeneration, and that it can inhibit influenza infections.

But not everyone reacts well to them. Swallow Birds Nest are known to cause anaphylaxis, a life-threatening allergic reaction.

Little research has been carried out on their biological function so far, and more is needed to better understand the qualities attributed to them, they conclude.

Healing Powers of Swallow Birds Nest Remain Mysterious

Classification by Country of Origin

Swallow Birds Nest only originate from South East Asia.
1) Indonesia – Texture is smoother, softer and cleaner with fewer impurities as the majority of the nests are harvested from Indonesia’s house nests. Indonesia produces approximately 80% of the world’s supply. Prices are generally lower.
2) Thailand – These Swallow Birds Nest are thicker and firmer with higher density thus it requires more soaking and cooking time. As the majority of the nests are cultivated from the caves with a small production volume, the prices are generally higher.
3) Malaysia – With higher production of feather prime nests Swallow Birds Nest, Swallow Birds Nest from Malaysia are usually processed into cakes and prices are low.
4) Vietnam – These Swallow Birds Nest are higher quality and richer taste and aroma due to an ideal environment conditions for Swallow Birds Nest in Vietnam. Swallow Birds Nest here are limited in supply and prices are higher.

Classification by Shape and Size

Being a natural food product, Swallow Birds Nest come in many different shapes and sizes:
1) Cup – Whole nest that ranges from large to extra large size (top grade).
2) Triangle – Triangular shaped Swallow Birds Nest that are medium in size.
3) Strips – Broken pieces from whole Swallow Birds Nest,
4) Cakes – Tiny Swallow Birds Nest pieces that are shaped into the shape and size of a biscuit.

Classification by Terrain

Swallow Birds Nests are harvested from only two types of terrain shown below:
1) House Nest – Swifts build their nests inside a house located near to the sea where the environment is ideal and more controlled; therefore leading to fewer impurities and feathers in the Swallow Birds Nest.
2) Cave Nest – Swifts build their nests on mountain and rock caves and cliffs near the sea. The natural climate and environment affects the texture which tends to be stiffer and harder. But generally cave nests contain more foreign materials and feathers than house nests.

Classification by pre-cleaning quality

Type of Swallow Birds Nest prior to cleaning processing.
1) Premium (Aerodramus Fuciphagus) nests – Consist of 95% saliva and 5% feathers
2) Feather prime nests – Consist of 50% saliva and 50% feathers
3) Grass nests – Consist of 5% saliva with grass and twigs