Effects of Prune (Dried Plum) Supplementation on Cardiometabolic Health in Postmenopausal Women: An Ancillary Analysis of a 12-month Randomized Controlled Trial, The Prune Study

Background Estrogen withdrawal during menopause is associated with an unfavorable cardiometabolic profile. Prunes (dried plums) represent an emerging functional food and have been previously demonstrated to improve bone health. However, our understanding of the effects of daily prune intake on cardiometabolic risk factors in postmenopausal women is limited. Objective We conducted an ancillary investigation of a randomized controlled trial (RCT), The Prune Study, to evaluate the effect of 12-month prune supplementation on cardiometabolic health markers in postmenopausal women. Methods The Prune Study was a single-center, parallel-design, 12-month RCT in which postmenopausal women were allocated to no-prune control, 50g/day prune, or 100g/day prune groups. Blood was collected at baseline, 6 months, and 12 months/post to measure markers of glycemic control and blood lipids. Body composition was assessed at baseline, 6 months, and 12 months/post using dual-energy X-ray absorptiometry. Linear mixed-effects model was used to evaluate the effect of time, treatment, and their interaction on cardiometabolic health markers, all quantified as exploratory outcomes. Results A total of 183 postmenopausal women [mean ± SD; age, 62.1 ± 4.9 years] completed the entire 12-month RCT: control (n=70), 50g/day prune (n=67), and 100g/day prune (n=46). Prune supplementation at 50g or 100g/day did not alter markers of glycemic control and blood lipids after 12 months compared to the control group (all p>0.05). Furthermore, gynoid percent fat and visceral adipose tissue indices did not significantly differ in women consuming 50g or 100g/day prunes compared to the control group after 12 months of intervention. However, android total mass increased by 3.19±5.5% from baseline in the control group, while the 100g/day prune group experienced 0.02±5.6% decrease in android total mass from baseline (p<0.01). Conclusions Prune supplementation at 50g/day or 100g/day for 12 months did not improve glycemic control and may prevent adverse changes in central adiposity in postmenopausal women.This trial was registered at clinicaltrials.gov as NCT02822378 Clinical Trials Registry Number / Website NCT02822378 / ClinicalTrials.gov