Published in The American Journal of Clinical Nutrition, the RENEW project (valoRization of dairy side-streams to fight calcium dEficits iN postmEnopausal Women) set out to establish if calcium-rich permeate could be used as a bioactive food ingredient to counteract bone loss.
In the 12-month intervention study, 316 participants were randomized to a placebo or 800mg of calcium, either from calcium carbonate or from calcium-rich whey permeate (taken alone or with inulin), divided into two doses per day. They all also received vitamin D, which contributes to the maintenance of normal bones.
In the group receiving whey permeate high in calcium (n=78), bone mineral density was maintained. Whereas, participants in the placebo group (n=75) showed a reduction in bone mineral density after 12 months. In addition, blood markers of bone turnover indicated a noticeable slowing of bone loss by the third month of the whey permeate intervention.
Adding inulin to the calcium-rich whey permeate did not provide any additional bone health benefits.
The supplement used in the study contained Capolac, a natural milk mineral concentrate rich in calcium and other minerals, and Variolac, a whey permeate and a cost-effective alternative to traditional milk solids, supplied by Arla Foods Ingredients.
“Globally, approximately one in five older adults has osteoporosis,” said Simon Bøge Riis, nutrition scientist at Arla Foods Ingredients. “It’s especially common among postmenopausal women and across Asia, underscoring the need for effective nutritional strategies to support bone health.”
“This research demonstrates that twice-daily supplementation with calcium-rich whey permeate can deliver remarkable improvements in bone turnover markers and maintain bone mineral density in postmenopausal women,”
Bone mineral density in menopause
In the early menopausal years, women experience a rapid loss of bone mineral density, which is an indicator of bone health. This is partly due to a significant decline in estrogen levels, which accelerates bone breakdown and increases the risk of osteoporosis.
Calcium is essential for skeletal development and maintenance. Adequate intake is especially important after menopause to counteract increased bone resorption. While many postmenopausal women may choose to supplement calcium, supplement form influences absorption and efficacy, creating demand for alternative sources, according to the study report.
Inulin, a non-digestible, fermentable fructo-oligosaccharide, can increase the short-chain fatty acid production and has previously been found to improve bone turnover markers in postmenopausal females. The researchers in this study therefore tested the influence of adding inulin to the supplementation protocol.
The RENEW study
The RENEW study was a multi-center trial conducted in joint partnership between Arla Foods Ingredients, Arla Foods amba, the University of Copenhagen, Zealand University Hospital, Aarhus University and the USDA Western Human Nutrition Research Center.
After recruitment and randomization, the participants attended the test centers six times across the 12 months of study.
Researchers obtained fasted and non-fasted blood samples in order to analyze vitamin D status and bone turnover markers (CTX and PINP). Subjects underwent DXA scans to assess bone mineral density (BMD) at the lumbar spine, femoral neck, and proximal femur.
Participants also completed the dietary intake assessment tool myfood24 and the short version of the International Physical Activity Questionnaire. Researchers took anthropometric measurements and bioelectrical impedance outcomes were recorded. Blood pressure and pulse rate were also measured.
The resulting data indicated the placebo group experienced a mean rate of BMD loss of approximately 1% over the year. Bone turnover markers CTX and PINP declined in all three calcium- supplemented groups at 3 and 12 months.
According to the report, over the 12-month intervention, the treatments “evoked distinct effects on iPTH” (intact parathyroid hormone), a key regulator of calcium homeostasis that raises blood calcium concentrations by prompting bones to release calcium and enhances calcium absorption in the intestine. iPTH was significantly suppressed in the CC and CP-Inu groups, suggesting higher circulating calcium availability along with a reduced need to mobilize calcium from the bone.
Whey protein side stream
Whey permeate is a dairy byproduct created when liquid whey is filtered (via ultrafiltration or nanofiltration) to remove proteins and fats. The remaining liquid—consisting mostly of lactose, minerals, and trace elements—is concentrated and spray-dried into a fine, free-flowing powder.
The utilization of nutrition-rich side streams creates a more sustainable and efficient whey production process as well as creating the potential to develop innovative ingredients and product formats that are appealing and convenient for consumers.
“The development of affordable calcium-rich milk-based ingredients from whey production could be particularly relevant for developing countries, where calcium deficiency is an overlooked challenge.” said Bøge Riis. “Such ingredients may also be incorporated into food products aimed at addressing multiple nutritional deficiencies, including inadequate calcium intake and poor bone health.”
Source: The American Journal of Clinical Nutrition, DOI: 10.1016/j.ajcnut.2026.101339 External Link, “Effects of a one-year calcium-enriched permeate supplement on bone health in post-menopausal females: The RENEW randomized controlled intervention trial” Authors: Tetens, I., et al
