Should there be a dietary guideline for calcium intake? No

Nutritional associations with bone loss during the menopausal transition: evidence of a beneficial effect of calcium, alcohol, and fruit and vegetable nutrients and of a detrimental effect of fatty acids

BACKGROUND

The menopausal transition is characterized by rapid bone loss. Few data exist on the role of nutrition.

OBJECTIVE

The objective of the study was to ascertain which dietary factors influence perimenopausal skeletal loss.

DESIGN

A longitudinal study was conducted of 891 women aged 45-55 y at baseline and 50-59 y at follow-up 5-7 y later. Bone mineral density (BMD) was measured by using dual-energy X-ray absorptiometry at the lumbar spine and femoral neck (FN). Nutrient intakes were assessed after the baseline visit and 5 y later, by using the same food-frequency questionnaire.

RESULTS

After adjustment for energy intake and other confounders, higher intakes of calcium were correlated with change in FN BMD (ie, reduced loss) (r = 0.073, P < 0.05), and the intake of modest amounts of alcohol was associated with less lumbar spine bone loss (P < 0.01 for quartile of alcohol intake). Greater FN BMD loss was associated with increased intake of polyunsaturated fatty acids (r = -0.110, P < 0.01), monounsaturated fatty acids (r = -0.069, P < 0.05), retinol (r = -0.067; P < 0.05), and vitamin E (r = -0.110; P < 0.01). The latter 2 nutrients were highly correlated with polyunsaturated fatty acids. For premenopausal women, calcium and nutrients found in fruit and vegetables (vitamin C, magnesium, and potassium) were associated with FN BMD, and calcium, vitamin C, and magnesium were associated with change in FN BMD.

CONCLUSIONS

Although menopausal status and hormone replacement therapy use dominate women's bone health, diet may influence early postmenopausal bone loss. Fruit and vegetable intake may protect against premenopausal bone loss.

Calcium and vitamin D in osteoporosis

Calcium and vitamin D are useful adjunctive therapies in the prevention and treatment of osteoporosis. Peak BMD is optimally achieved with sustained optimal calcium and vitamin D intakes. Calcium and vitamin D intakes continue to be important after the third decade and into senescence. Although calcium and vitamin D are not therapies to be used alone to prevent early postmenopausal bone loss, they assume more prominent roles in late menopause and in the elderly to preserve bone health with advancing age. Calcium and vitamin D supplementation is an important adjunctive therapy to use together with antiresorptive therapies.