Americans are big on calcium. In fact, the number one supplement sold in America is calcium. What is not well known is that most Americans are also unknowingly buying and throwing away a bio-available form calcium supplement almost every day. If only they knew that eggshells can be used as a good source of bio-available calcium.
According to Dutch research eggshells have a very positive effect on bone density when combined with other minerals such as magnesium and zinc along with vitamin D according to a double blind placebo study. This information is corroborated by a Japanese study by the Japan Women's University. The Japanese study was done on a combination of eggshell calcium and vitamin D3, which was conducted on animals that were shown to have osteoporosis. The study concluded that the combination was able to raise bone density levels without significantly raising blood calcium levels.