Effect of a daily supplement of soy protein on body composition and insulin secretion in postmenopausal women.

Academic Article


  • OBJECTIVE: To determine whether a supplement of soy protein improves body composition, body fat distribution, and glucose and insulin metabolism in postmenopausal women without diabetes compared with an isocaloric casein placebo. DESIGN: Randomized, double-blind, placebo-controlled 3-month trial. SETTING: Clinical Research Center. PATIENT(S): Fifteen postmenopausal women. INTERVENTION(S): Computed tomographic scans at L4/L5, dual energy x-ray absorptiometry, hyperglycemic clamps. MAIN OUTCOME MEASURE(S): Total fat, total abdominal fat, visceral fat, subcutaneous abdominal fat, and insulin secretion. RESULT(S): Weight by dual energy x-ray absorptiometry did not change between groups (+1.38 +/- 2.02 kg for placebo vs. +0.756 +/- 1.32 kg for soy, mean +/- SD). Total and subcutaneous abdominal fat increased more in the placebo group than in the soy group (for differences between groups in total abdominal fat: +38.62 +/- 22.84 cm(2) for placebo vs. -11.86 +/- 31.48 cm(2) for soy; subcutaneous abdominal fat: +22.91 +/- 28.58 cm(2) for placebo vs. -14.73 +/- 22.26 cm(2) for soy). Insulin secretion, visceral fat, total body fat, and lean mass did not differ between groups. Isoflavone levels increased more in the soy group. CONCLUSION(S): A daily supplement of soy protein prevents the increase in subcutaneous and total abdominal fat observed with an isocaloric casein placebo in postmenopausal women.
  • Published In


  • Abdominal Fat, Blood Glucose, Body Composition, Dietary Supplements, Double-Blind Method, Drug Administration Schedule, Female, Humans, Insulin, Insulin Secretion, Intra-Abdominal Fat, Isoflavones, Middle Aged, Placebos, Postmenopause, Soybean Proteins, Tomography, X-Ray Computed
  • Digital Object Identifier (doi)

    Author List

  • Sites CK; Cooper BC; Toth MJ; Gastaldelli A; Arabshahi A; Barnes S
  • Start Page

  • 1609
  • End Page

  • 1617
  • Volume

  • 88
  • Issue

  • 6