Plum Efficacy

Plum efficacy

In a rat model of atherosclerosis, dried plums (Prunus domestica L.) at low dose reduced lesion areas in the aorta compared to cholesterol-fed rats. This effect was attributed to a reduction in total and LDL-cholesterol in the blood. In addition, plums reduced atherosclerotic plaque growth in the aortic wall by promoting the deposition of nitric oxide and inhibiting lipid peroxidation. These effects have been attributed to increased expression of peroxisome proliferator-activated receptor-a, enhanced insulin activity, inhibition of HMG-CoA and acyl-CoA:cholesterol acyl transferase, and enhancement of oxidative metabolism, including lipolysis.(36)
Dried plums have also been found to be effective in lowering serum cholesterol in human studies, although these results are more mixed and require further investigation. The impact of dried plums on circulating cholesterol is thought to be mediated via their high content of dietary fibre, which reduces plasma cholesterol and improves insulin sensitivity. The plums also contain phenolic compounds, which increase plasma antioxidant capacity and decrease serum LDL-cholesterol.(37)

Plums have a very high mineral content, particularly potassium, calcium and magnesium. This may explain why animal and clinical studies show that dried plums can both prevent and reverse osteoporosis in humans. Animal studies also show that plums, when fed to growing and young mice, significantly increase bone volume. Dried plums (DP) also reduce the amount of calcium excreted in the urine by suppressing the formation of bone-resorbing osteoclasts. Plums also promote bone accumulation by increasing plasma phosphorus and stimulating osteoblast activity. DP also increases the concentrations of hydroxyproline and total phenolics, and reduces inflammatory factors such as interleukin-6 and tumor necrosis factor-alpha.

In a three-month clinical trial, dried plums (DP) at two different dose levels were shown to be effective in preventing bone loss in postmenopausal women. Total body, hip and lumbar bone mineral density (BMD) was measured with dual-energy X-ray absorptimetry at baseline and after six months of treatment. Blood samples were obtained at three and six months to measure biomarkers of bone turnover, including tartrate resistant acid phosphatase-5b (TRAP-5b, a marker of bone resorption), high-sensitivity C-reactive protein (hs-CRP) and insulin-like growth factor-1. DP at both doses prevented the loss of BMD in comparison to control, and at the lower dose, induced a small but significant improvement in lumbar and hip BMD.

The same study also reported that consuming plums reduced indices of inflammation and oxidative stress in the blood. In contrast to a control group, the DP groups showed lower total WBC counts and absolute differentials of neutrophils, monocytes, eosinophils and basophils.

Several other animal and clinical studies suggest that a daily intake of 100 g dried plums/prunes is beneficial for both men and women. Dried plums are also able to restore bone in a postmenopausal women with osteopenia, and are one of the most efficacious non-pharmacological therapies available for improving BMD in this patient population. In this population, a higher dose of dried plums is needed to achieve a greater bone-protective effect.