Coadministration of egg chalaza with CaCO3 dose-dependently increased apparent calcium absorption and retention, enhanced bone calcium deposition, and improved bone microarchitecture and mechanical properties compared with CaCO3 alone in a low-calcium growing rat model.
Chalaza coadministered with CaCO3 dose-dependently increased apparent calcium absorption and retention compared to CaCO3 alone in low-calcium growing rats.
Chalaza coadministration with CaCO3 enhanced bone calcium deposition and improved bone microarchitecture and mechanical properties.
Chalaza treatment was associated with improved duodenal morphology and upregulation of intestinal calcium transport-related proteins.
Chalaza treatment was associated with changes in gut microbiota composition and short-chain fatty acid (SCFA) levels.
Digestion-derived peptides from chalaza demonstrated calcium-chelating capacity, inhibition of calcium phosphate crystallization, gastrointestinal calcium release, and thermal stability.
Chalaza (CLZ) is identified as a byproduct generated during egg processing with potential to promote calcium absorption.
This research suggests that the chalaza — the small, twisted strand found inside eggs that anchors the yolk — can meaningfully improve how the body absorbs and uses calcium when taken alongside a common calcium supplement (calcium carbonate). Using young rats fed a low-calcium diet, researchers found that adding chalaza to calcium carbonate supplements led to better calcium absorption, more calcium deposited in bones, and stronger, better-structured bones compared to calcium carbonate alone, with the benefits increasing as the dose of chalaza increased. The study also identified several mechanisms that may explain why chalaza helps. Animals receiving chalaza showed healthier intestinal tissue in the duodenum (the first part of the small intestine, where most calcium is absorbed), as well as higher levels of three key proteins that the gut uses to transport calcium across the intestinal wall. Additionally, the gut bacteria and their metabolic byproducts (short-chain fatty acids) were altered in ways that may further support calcium absorption. When the researchers broke down chalaza proteins through simulated digestion, the resulting peptides showed an ability to bind calcium, prevent calcium from forming insoluble crystals, and release calcium under stomach and intestinal conditions — all properties that could help keep calcium available for absorption. This research suggests that chalaza, currently discarded as a waste product in commercial egg processing, could be repurposed as a functional ingredient in calcium supplements or fortified foods. For people who struggle with calcium deficiency — such as growing children, older adults, or postmenopausal women — adding chalaza-derived ingredients to calcium supplements might represent a more effective strategy than calcium supplements alone. The findings also highlight a broader opportunity to extract value from food industry byproducts rather than discarding them.
Wang S, Qi Y, Zhou Q, Liang H, Li B, Li J. (2026). Egg Chalaza Improves Calcium Utilization in Growing Rats: Evidence from Intestinal Aspects.. Journal of agricultural and food chemistry. https://doi.org/10.1021/acs.jafc.6c04901