Spinal Bone Loss in Postmenopausal Women Supplemented with Calcium and Trace Minerals

Abstract

The effects of calcium supplementation (as calcium citrate malate, 1000 mg elemental Ca/d) with and without the addition of zinc (15.0 mg/d), manganese (5.0 mg/d) and copper (2.5 mg/d) on spinal bone loss (L2-L4 vertebrae) was evaluated in healthy older postmenopausal women (n = 59, mean age 66 y) in a 2-y, double-blind, placebo-controlled trial. Changes (mean +/- SEM) in bone density were -3.53 +/- 1.24% (placebo), -1.89 +/- 1.40% (trace minerals only), -1.25 +/- 1.46% (calcium only) and 1.48 +/- 1.40% (calcium plus trace minerals). Bone loss relative to base-line value was significant (P = 0.0061) in the placebo group but not in the groups receiving trace minerals alone, calcium alone, or calcium plus trace minerals. The only significant group difference occurred between the placebo group and the group receiving calcium plus trace minerals (P = 0.0099). These data suggest that bone loss in calcium-supplemented, older postmenopausal women can be further arrested by concomitant increases in trace mineral intake.

Reported zinc, but not copper, intakes influence whole-body bone density, mineral content and T score responses to zinc and copper supplementation in healthy postmenopausal women

“…Cu and Zn supplementation did not provide further benefit to bone compositional characteristics, and a priori contrasts indicate that the Cu and Zn supplement was detrimental by year 2 to any beneficial effect of the Ca and vitamin D supplementation. This finding was just the opposite of that of Strause et al (1) who found that a cocktail of Cu, Zn and Mn enhanced the effect of Ca supplementation on bone mineral density, and was not consistent with the finding that Cu supplementation prevented vertebral trabecular bone density loss (2) . Thus, a possible explanation for the discordant findings was sought.…”

“…The inferior bone status is consistent with animal studies and premature infant supplementations showing that bone formation is impaired by a Cu-deficient state (3,4,6,7) . It is unclear why a positive response to the 2 mg/d Cu supplement was not obtained in women with Cu intakes , the RDA, which would be inconsistent with the findings of Strause et al (1) and Eaton-Evans et al (2) that Cu supplementation at about three times the RDA was beneficial to bone mineral density. Perhaps another environmental or nutritional factor promoting bone loss or poor Ca utilisation inhibited the response to Cu supplementation.…”

“…In rats, Cu deprivation decreased mechanical strength and changed the organic and inorganic composition of femurs (6,7) . In addition to Strause et al (1) including Zn as a component in their trace element cocktail supplement study, this research group reported that Zn was decreased in bones of osteoporotic patients (8) . Bone growth retardation is common in different growing animal models, and animal and cell-culture experiments show that Zn is involved in or affects several metabolic pathways of bone turnover (9) .…”

A moderately high intake compared to a low intake of zinc depresses magnesium balance and alters indices of bone turnover in postmenopausal women

“…Zinc deficiency in animals, including chicks, cows, pigs, monkeys, and rats results in delayed or defective mineralization, widened growth plates, indistinct zones of provisional calcification, and malformed bones (Hurley, 1981;Yamaguchi, 1998). Both copper and zinc supplementations have been shown to inhibit bone loss in adult humans (Strause et al, 1994;Eaton-Evans et al, 1996).…”

“…The zinc:copper ratios ranged from 1 to 53 in the experimental diets. Postmenopausal women were chosen to be subjects in the study because they were employed in studies showing an effect of copper (EatonEvans et al, 1996) and zinc (Strause et al, 1994) on bone loss, and because of their susceptibility to osteoporosis.…”