Antiaging benefits of hyaluronic acid: available as a cream or supplement, hyaluronic acid is used to fight wrinkles and joint pain, and promote wound healing.(PERSONAL CARE: INSIDE & OUT)

It sounds like science fiction, but it's not--a macromolecule that eases swollen joints, smoothes wrinkles, reduces scarring and heals wounds and cataracts. Hyaluronic acid (HA), also known as hyaluronan, is a naturally occurring complex carbohydrate present in our connective tissues. The nutrient's gelatin-like consistency is what hydrates body tissues and gives them structure. You'll find HA in almost any living creature--humans, animals and even microorganisms.

Since its discovery in 1934, the use of HA has become increasingly popular for widely varied applications: as an egg white substitute for baking, a unique eye surgery aid, an injectable treatment for knee osteoarthritis, and the cosmetic dermal filler Restylane.

But it doesn't take a trip to your bakery or doctor to see and feel the benefits of HA. There are a number of natural products that feature it, and for good reason.

How HA Works

"HA has an enormous capacity to absorb water and therefore possesses an excellent hydration capacity," says Tracey Brown, PhD, an associate professor and HA researcher at Australia's Monash University. This ability, she explains, is why HA seems to temporarily decrease the appearance of wrinkles.

"When the correct HA formulation is used topically, HA enters into the skin and deposits itself in the basal epidermal layer, where it attracts extracellular fluids and could present a reduction in wrinkles," she says.

HA is also available as an oral supplement, often in combination with other joint healers like glucosamine, chondroitin and MSM. There is some debate, however, as to whether any form of orally ingested HA is effective at repairing tissues. Says Brown, "In digestion, the HA would be degraded ...