A review of the experimental studies relating boron to biological effe
cts on appendicular and axial bones in animal models suggests that num
erous influences, known and unknown, affect the responsiveness of bone
to dietary boron. Degrees of skeletal response to boron are modified
by other nutritional variables that include calcium, magnesium, vitami
n D, and fluoride. Evidence suggests that appendicular and axial bones
may differ in their responses. Tests of the mechanical properties of
bones may provide useful criteria for assessing the impacts of boron s
tatus on bone. These tests might resolve questions about optimal intak
es of boron because mechanical properties sometimes respond to boron w
hen composition of bones does not. Difficulty in interpreting some of
the existing research arises because of the incipient state of knowled
ge regarding boron nutriture. to analytical problems associated with d
etermining accurately the small quantities of boron in feed and tissue
s, and to technological difficulties in controlling extraneous exposur
e of experimental animals to boron. Yet there is considerable evidence
that both compositional and functional properties of bone are affecte
d by boron status.