Researchers closer to finding how dried plums boost bone health

Fifty-seven million Americans suffer from low bone density or osteoporosis, a disease which causes bones to become so weak and brittle that even a minor fall or other stresses may cause fractures. A study published in the British Journal of Nutrition in July examined the mechanism of the bone-protective properties of California dried plums.1

To understand the mechanism by which bone health can be improved by eating plums, researchers from San Diego State University and Florida State University in the US used data collected from a previous 12-month clinical trial that compared the bone-protective effects of dried plums and dried apples.2

Results confirmed the bone-protective properties of dried plums, and several animal studies have also supported this finding. However, the mechanisms by which dried plums impart their bone-protective properties remain unclear.

Research suggests that dried plums may actually help to regenerate bone in people who have experienced bone loss

'While it is difficult to identify the exact mechanism behind dried plums' positive effect on bones, this study identified three potential pathways for the mechanism behind the effect of dried plums on bone resorption and bone formation,' said Shirin Hooshmand, Assistant Professor Department of Exercise and Nutritional Sciences at San Diego State University. 'We are excited to continue to apply the results of this study to future research that may help us to determine the exact link between dried plums and healthy bones.'

During the original 12-month clinical trial, which was published in 2011 in the British Journal of Nutrition, 160 osteopenic, postmenopausal women were randomly assigned to eat either 100g of dried plums (about 10 fruits) daily or 75g of dried apple daily. Each participant also received 500mg of calcium plus a daily vitamin D supplement (400 international units).

The results indicated that the group that consumed dried plums had significantly higher bone mineral density in the ulna and spine, in comparison with the group that ate dried apples.

This, according to study author and researcher Bahram Arjmandi, Florida State University's Margaret A. Sitton Professor of the Department of Nutrition, Food and Exercise Sciences and Director of the Centre for Advancing Exercise and Nutrition Research on Ageing (CAENRA) in the College of Human Sciences, was due, in part, to the ability of dried plums to suppress the rate of bone resorption, or the breakdown of bone, which tends to exceed the rate of new bone growth as people age.

'Nature has created dried plums to be unique in nutrient composition. They really are the whole package,' said Arjmandi. 'In more than 15 years of research, I have never seen a fruit like dried plums. Research suggests that they may actually help to regenerate bone in people who have experienced bone loss.'

Results of additional animal studies which measured effects on bone mineral density are consistent, showing strong supporting evidence of an effect of dried plums on bone mineral density and/or markers of bone turnover. Collectively, both the human and animal studies indicate that adding dried plums to the diet may be an effective way to help support healthy bones.

Research also suggests that dried plums may support heart health and digestive health and may improve satiety.

The original 12-month clinical study published in 2011 was funded by the National Research Initiative of the USDA Cooperative State Research, Education and Extension Service. The California Dried Plum Board provided some funding for the study, as well as dried plums for participants.

References

1. British Journal of Nutrition/Volume 112/Issue 01/July 2014, pp 55–60

2. British Journal of Nutrition (2011), 106, 923–930