Effects of dietary flaxseed lignan extract on symptoms of benign prostatic hyperplasia.

ABSTRACT A flaxseed lignan extract containing 33% secoisolariciresinol diglucoside (SDG) was evaluated for its ability to alleviate lower urinary tract symptoms (LUTS) in 87 subjects with benign prostatic hyperplasia (BPH). A randomized, double-blind, placebo-controlled clinical trial with repeated measurements was conducted over a 4-month period using treatment dosages of 0 (placebo), 300, or 600 mg/day SDG. After 4 months of treatment, 78 of the 87 subjects completed the study. For the 0, 300, and 600 mg/day SDG groups, respectively, the International Prostate Symptom Score (IPSS) decreased −3.67 ± 1.56, −7.33 ± 1.18, and −6.88 ± 1.43 (mean ± SE, P = .100, < .001, and < .001 compared to baseline), the Quality of Life score (QOL score) improved by −0.71 ± 0.23, −1.48 ± 0.24, and −1.75 ± 0.25 (mean ± SE, P = .163 and .012 compared to placebo and P = .103, < .001, and < .001 compared to baseline), and the number of subjects whose LUTS grade changed from “moderate/severe” to “mild” increased by three, six, ...