By: Pallavi Vathiar. Practicing Clinical Nutritionist, Mumbai.
Eggshells consists mostly of calcium carbonate, a common form of calcium, the rest is made up of protein and other minerals. In the past decades, eggshell powder processed from hen eggs has been used as a natural calcium supplement. Eggshells are roughly 40% calcium, with each gram providing 381–401 mg. Half an eggshell may provide enough calcium to meet the daily requirements for adults, which is 1,000 mg per day (1).
Calcium carbonate is the most common form of calcium in nature, making up seashells, coral reefs and limestone. Its absorption is better than that of purified calcium carbonate supplements. A study in isolated cells found that calcium absorption was up to 64% greater from eggshell powder compared to pure calcium carbonate. Researchers attributed these effects to certain proteins found in eggshells (2).
The eggshell membrane is located between the eggshell and the egg white. It is easily visible when you peel a boiled egg. It also contains small amounts of chondroitin sulfate, glucosamine and other nutrients. Studies show that regular intake of eggshell membrane supplements may benefit bone joints (3,4,5). Eggshell membrane mainly consists of protein in the form of collagen.
The oldest glue ever used, dated some 8000 years back was collagen. Collagen is applied to hold utensils and is also very useful for musical instruments like the violin and guitars which have to be opened frequently for repairs. Collagen on reheating can be softened easily unlike the synthetic plastic adhesives which are permanent. Collagen is used for cosmetic and burns surgery
Osteoporosis is a health condition characterized by weak bones and an increased risk of bone fractures. Old age is one of the strongest risk factors for osteoporosis, but inadequate calcium intake may also contribute to bone loss and osteoporosis over time. A study conducted in postmenopausal women with osteoporosis found that taking eggshell powder, along with vitamin D3 and magnesium, significantly strengthened their bones by improving bone mineral density (6). It is also been observed that eggshell powder improved bone mineral density in the neck compared to a placebo. In contrast, purified calcium carbonate did not significantly improve it (7).
When prepared correctly, eggshell powder is considered safe. There are just a few things you need to keep in mind.
Do not attempt to swallow large fragments of eggshell as they might injure your throat and esophagus rather grind eggshells into powder.
Eggshells may be contaminated with bacteria, such as Salmonella enteritidis. To avoid the risk of food poisoning, make sure to boil eggs before eating their shell (8).
Its always better to boil it thoroughly and grind it into fine powder.
Store it an air tight jar and consume 1tablespoon with pure honey.
Eggshells from the hatcheries, fast food industries and homes should not be disposed in a waythat pollutes the environment.