Objective: To test the hypothesis that a low-fat, vegetarian diet reduces d
ysmenorrhea and premenstrual symptoms by its effect on serum sex-hormone bi
nding globulin concentration and estrogen activity.
Methods: In a crossover design, 33 women followed a low-fat, vegetarian die
t for two menstrual cycles. For two additional cycles, they followed their
customary diet while taking a supplement placebo pill. Dietary intake, seru
m sex-hormone binding globulin concentration, body weight, pain duration an
d intensity, and premenstrual symptoms were assessed during each study phas
e.
Results: Mean (+/- standard deviation [SDI]) serum sex-hormone binding glob
ulin concentration was higher during the diet phase (46.7 +/- 23.6 nmol/L)
than during the supplement phase (39.3 +/- 19.8 nmol/L, P < .001). Mean (+/
- SD) body weight was lower during the diet (66.1 +/- 11.3 kg) compared wit
h the supplement phase (67.9 +/- 12.1 kg, P <.001). Mean dysmenorrhea durat
ion fell significantly from baseline (3.9 +/- 1.7 days) to diet phase (2.7
+/- 1.9 days) compared with change from baseline to supplement phase (3.6 /- 1.7 days, P < .01). Pain intensity fell significantly during the diet ph
ase, compared with baseline, for the worst, second-worst, and third-worst d
ays, and mean durations of premenstrual concentration, behavioral change, a
nd water retention symptoms were reduced significantly, compared with the s
upplement phase.
Conclusion: A low-fat vegetarian diet was associated with increased serum s
ex-hormone binding globulin concentration and reductions in body weight, dy
smenorrhea duration and intensity, and premenstrual symptom duration. The s
ymptom effects might be mediated by dietary influences on estrogen activity
. (C) 2000 by The American College of Obstetricians and Gynecologists.