Adding zinc reduces bone strength of rats fed a low-calcium diet.
This experiment examined skeletal effects of moderate zinc (Zn) supplementation of a low-calcium diet. Male weanling rats were fed experimental diets for about 4 wk. One diet was adequate (control), whereas two others were calcium-deficient, but otherwise adequate. One of the low-calcium (Ca) diets was supplemented with Zn. Dimensions, weight, mineral content, and mechanical properties of femurs were measured. Ca deficiency reduced bone mineral content and strength markedly. Adding Zn to the low-Ca diet further reduced bone strength and elasticity, compared with the unsupplemented low-Ca diet. When the Ca intake is low, possible benefits of Zn supplements should be weighted against risk of deterioration of mechanical properties of bone.
Kenney
M A
MA
School of Human Environmental Sciences, University of Arkansas, Fayetteville 72701, USA.
McCoy
H
H
D000818:Animals; D015519:Bone Density / Q000187:drug effects*; D002118:Calcium / Q000172:deficiency*; D002136:Calcium, Dietary / Q000494:pharmacology; D019587:Dietary Supplements; D005269:Femur / Q000254:growth & development; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D013054:Spectrophotometry, Atomic; D015032:Zinc / Q000378:metabolism / Q000494:pharmacology*
D002136:Calcium, Dietary; D015032:Zinc; D002118:Calcium