Nano-sized calcium improves bioavailability and could aid osteoporosis fight
One out of four osteoporosis-related hip fractures happen in Asia, and this number is set to increase to one in two by 2050, according to research.
However, proper nutrition and effective calcium intake can reduce the numbers, said a study conducted by the Universiti Malaysia Sabah, and Universiti Putra Malaysia. The research suggested reducing calcium found in homogenised enriched milk into nanoparticles, to increase the nutrient’s bioavailability.
“Due to their small sizes, nanoparticles have various physiochemical properties in comparison with the respective bulk compounds,” they wrote. “Nano delivery system can modify the distribution of nutrients in the body. Therefore, they can enhance nutrients’ bioavailability.”
Enriched milk diets
To determine if nanoparticle calcium is better absorbed, researchers prepared two kinds of homogenised milk diets enriched with calcium nanoparticles. The nano-calcium carbonate and nano-calcium-citrate diets were tested on rats - either sham, ovariectomized and ovariectomized-osteoporosis.
After the prescribed period, blood, faeces and femur samples were collected from the sacrificed rats for calcium testing.
The findings revealed more calcium serum content found in bio samples from the sham, ovariectomised, and ovariectomised-osteoporosis rats fed with the nano-calcium-carbonate preparation. The rat groups that received the nano-calcium-citrate mix had slightly lower calcium serum compared to the first group.
“Although, nano-sized enriched milk powders had the greatest calcium bioavailability among the groups, [the] bioavailability of nano-sized calcium carbonate-enriched-milk was significantly (P < 0.05) better than nano-sized calcium citrate-enriched-milk,” they wrote.
“It was observed that, although the highest amounts of serum calcium belonged to the nano-sized calcium carbonate-enriched-milk groups, no significant (p = 0.21) difference was observed between the sham, ovariectomised and ovariectomised-osteoporosis groups.”
With fewer than 50% of postmenopausal women consuming an adequate dietary calcium intake, it is necessary to persuade them to consume calcium-enriched foods, the researchers said.
They now hope their work shows how carbonate nano-sized enriched milk could be an effective product.
They concluded: “The major finding was that bioavailability of calcium can be improved by reducing particle size, with the combination of composition (calcium carbonate/ calcium citrate, DHA & EPA, vitamins D3, B6, K1, and inulin) and reducing particle size could help to increase the calcium bioavailability,” researchers wrote.
“Also, the nano-sized calcium carbonate-enriched-milk was more effective than nano-sized calcium citrate-enriched-milk on bioavailability and absorption of calcium.
"Thus, such enriched milk products are recommended for subjects at risk of bone loss (especially women over 50 years of age). The knowledge gained through the experiments, outlined in this study, will help menopausal women to prevent and reduce bone loss. However, considerably more work need to be done to determine the mechanism of the system in human body."
Source: Food Chemistry
DOI: 10.1016/j.foodchem.2016.07.116
“Comparing the calcium bioavailability from two types of nano-sized enriched milk using in-vivo assay”
Authors: Arezoo Erfanian, Babak Rasti, and Yazid Manap
