I was 10 years old when I first encountered prunes. It was breakfast time at Girl Guide camp, and no one could leave the table without a mandatory serving of the sweet stewed fruit. Why were the girls groaning and giggling? With a food this delicious, why did there have to be a rule? It seems I’d come from a family where bowels moved on schedule without drama, so I hadn’t yet heard about the laxative effect of prunes.
Now prunes are becoming known for a new superpower: Reversing osteoporosis. Here’s what one study found:
In a clinical study of 58 women, eating 100 grams of dried plums per day improved bone formation markers after only three months, compared to a control group served 75g of dried apples.
It seems the first benefit to bones is from the high boron content of prunes. This stimulates the bone-building cells, the osteoblasts, and increases calcium absorption so less is lost in urine. It also helps convert vitamin D into the active form that helps direct the calcium into the bones. Then the polyphenols in prunes have an anti-inflammatory effect, inhibiting the osteoclasts, which are the clean-up cells that can be overactive in osteoporosis. More bone building and less bone removal? Higher density.
So the study I referenced above found that 100 grams of prunes per day would have a major impact on bone density. From what I learned at camp, that level of consumption would not be wise for someone like me, and on that point I won’t elaborate. However, it isn’t hard to fit a few prunes into my diet. These days I use them as a reward to cover the nasty taste of my daily silicon drops.
One concern about prunes is that they are slightly acid-forming in the body, and too much acid has a negative impact on bone density. As part of a diet balanced by alkaline foods, though, a few prunes can really encourage bone health.