1. Calcium content and bioavailability
Eggshells consist primarily of calcium carbonate, which makes up about 95% of their composition. On average, one eggshell contains approximately 750 to 800 mg of elemental calcium. This is a significant amount considering the daily calcium intake recommended for most adults ranges from 1,000 to 1,200 mg, depending on age and health status.
Calcium from eggshells is highly bioavailable, meaning the body can absorb and utilize it efficiently. Research comparing eggshell calcium to other common calcium supplements, such as calcium carbonate tablets, suggests that eggshell-derived calcium is at least as well absorbed. This makes it a practical and natural source for supporting bone mineral density, which is crucial for preventing conditions like osteoporosis.
2. Collagen and membrane proteins
The thin membrane lining the inside of the eggshell contains a rich variety of proteins, including collagen types I and V. Collagen is a key structural protein found in connective tissues such as cartilage, tendons, and ligaments. Its presence in the eggshell membrane contributes to the structural integrity and flexibility of joints.
In addition to collagen, the eggshell membrane contains other proteins that support the extracellular matrix of joint tissues. These proteins may help maintain cartilage health by providing building blocks necessary for repair and regeneration. Including eggshell membrane components in the diet has been linked to improved joint function in some clinical studies, highlighting the potential benefits of these proteins for people experiencing joint discomfort.
