Hyaluronic acid is found throughout our body. Each body part has different optimal hyaluronic acid concentrations. The hyaluronic acid-richest parts are umbilical cord, joint fluid, vitreous body of the eye and skin.
The vitreous body is the clear gelatinous fluid that fills the area inside the eyeball, behind the lens. It contains large amounts of hyaluronic acid and plays a role in the maintaining of the eyeball's round shape.
The skin is broadly composed of three layers (from the outside): the epidermis (surface skin), dermis (inner skin) and subcutaneous tissue (tissue under the skin).
The dermis is about 10 times thicker than the epidermis, and contains large amounts of hyaluronic acid, which plays a role in preventing the skin from drying out.
Joints contain fluid that is composed of large amounts of hyaluronic acid. Hyaluronic acid allows joints to move smoothly.
The concentration of hyaluronic acid in the body decreases with aging. It has been reported that the concentration in skin starts to decrease in the late 40’s.