Decreases in bone mineral in lactating mothers
have been well documented. Typically, during
3 to 6 months of lactation, bone mineral density
is reduced by 3 to 5 percent at the spine and
neck, and by 1 to 2 percent in the whole body.
This bone mineral loss is similar or greater
to women shortly after menopause. These losses
are reversed in subsequent lactation and after
the end of breastfeeding, possibly in connection
with the return of menses. This kind of bone
mineral loss occurs even in women with a high
She concludes that lactation is associated possibly
with an alteration in calcium metabolism. This
includes the temporary mobilization and subsequent
replacement of bone mineral. Moreover, this
is independent of dietary calcium intake and
unresponsive to increases in calcium intake.
This does not mean that good nutrition, including
maintaining adequate calcium intake is not important
during lactation. However, the accumulating
scientific data suggests that breastfeeding
women need not consume extra calcium.
from the Editorial by Ann Prentice in The New
England Journal of Medicine, Aug 1997)