Potassium, magnesium, and fruit and vegetable intakes are associated with greater bone mineral density in elderly men and women

Background: Osteoporosis and related fractures will be growing public healt h problems as the population ages. It is therefore of great importance to i dentify modifiable risk factors. Objective: We investigated associations between dietary components contribu ting to an alkaline environment (dietary potassium, magnesium, and fruit an d vegetables) and bone mineral density (BMD) in elderly subjects. Design: Dietary intake measures were associated with both cross-sectional ( baseline) and 4-y longitudinal change in BMD among surviving members of the original cohort of the Framingham Heart Study. Dietary and supplement inta kes were assessed by food-frequency questionnaire, and BMD was measured at 3 hip sites and 1 forearm site. Results: Greater potassium intake was significantly associated with greater BMD at all 4 sites for men and at 3 sites for women (P < 0.05). Magnesium intake was associated with greater BMD at one hip site for both men and wom en and in the forearm for men. Fruit and vegetable intake was associated wi th BMD at 3 sites for men and 2 for women. Greater intakes of potassium and magnesium were also each associated with less decline in BMD at 2 hip site s, and greater fruit and vegetable intake was associated with less decline at 1 hip site, in men. There were no significant associations between basel ine diet and subsequent bone loss in women. Conclusion: These results support the hypothesis that alkaline-producing di etary components, specifically, potassium, magnesium, and fruit and vegetab les, contribute to maintenance of BMD.