Effects of a 1-year calcium-enriched permeate supplement on bone health in postmenopausal females: The RENEW randomized controlled intervention trial.

BACKGROUND

Osteoporosis is a common age-related skeletal disorder, especially in postmenopausal females, underscoring the need for effective nutritional strategies to preserve bone health. Calcium-enriched permeate (CP) and inulin may enhance absorption and bone mineral density (BMD).

OBJECTIVES

To assess the effects of daily supplementation of calcium-enriched permeate, with inulin (CP-Inu) or without inulin, and calcium carbonate (CC) on bone turnover markers and BMD in vitamin D-sufficient postmenopausal females.

METHODS

In this 12-mo randomized, double-blind, multi-center trial, postmenopausal females were allocated to receive daily either a maltodextrin as placebo (P), 800 mg calcium as CC, CP, or CP-Inu split into 2 doses. All received 20 μg vitamin D per day. Primary outcome was C-terminal telopeptides of type I collagen; secondary outcomes were procollagen type I N-terminal propeptide and BMD. Linear mixed-effects models were used to assess fixed and random effects. adjusted for multiple outcomes.

RESULTS

Of 417 participants (56.0 ± 4.2 y; BMI 25.5 ± 3.8), 316 (76%) completed the study with a mean 89% overall compliance. C-terminal telopeptides of type I collagen remained unchanged from baseline to 12 mo in the P group, whereas all intervention groups showed significant reductions compared with P (μg/L) [CC: β = -0.137; 95% confidence interval (CI): -0.193, -0.081, P = 2.59 × 10-6; CP: β: = -0.150; 95% CI: -0.208, -0.093, P = 1.62 × 10-6; CP-Inu β: = -0.149; 95% CI: -0.207, -0.090, P = 1.96 × 10-6]. Compared with P, procollagen type I N-terminal propeptide was significantly reduced in all intervention groups. By month 12, spine BMD (grams per square centimeter) was higher with CC: β = 0.0158, (0.0066, 0.0251), P = 0.0009; CP-Inu, β = 0.0142, (0.0046, 0.0238), P = 0.0040, and femoral neck BMD was higher with CP, β = 0.0116, (0.0042, 0.0190), P = 0.0022. No additional effects were observed in the CP-Inu group.

CONCLUSIONS

Daily supplementation of 800 mg calcium in 2 doses from CP suppresses bone turnover markers and maintains BMD similarly to CC in vitamin D-sufficient postmenopausal females. Inulin provides no additional advantage. This trial was registered at clinicaltrials.gov as NCT04836637.