Beneficial effects of soy phytoestrogen intake in postmenopausal women with type 2 diabetes

Diabetes Care. 2002 Oct;25(10):1709-14. doi: 10.2337/diacare.25.10.1709.

Abstract

Objective: Phytoestrogen consumption has been shown to reduce risk factors for cardiovascular disease. Type 2 diabetes confers an adverse cardiovascular risk profile particularly in women after menopause. The aim of this study was to determine whether a dietary supplement with soy protein and isoflavones affected insulin resistance, glycemic control, and cardiovascular risk markers in postmenopausal women with type 2 diabetes.

Research design and methods: A total of 32 postmenopausal women with diet-controlled type 2 diabetes completed a randomized, double blind, cross-over trial of dietary supplementation with phytoestrogens (soy protein 30 g/day, isoflavones 132 mg/day) versus placebo (cellulose 30 g/day) for 12 weeks, separated by a 2-week washout period.

Results: Compliance with the dietary supplementation was >90% for both treatment phases. When compared with the mean percentage change from baseline seen after 12 weeks of placebo, phytoestrogen supplementation demonstrated significantly lower mean values for fasting insulin (mean +/- SD 8.09 +/- 21.9%, P = 0.006), insulin resistance (6.47 +/- 27.7%, P = 0.003), HbA(1c) (0.64 +/- 3.19%, P = 0.048), total cholesterol (4.07 +/- 8.13%, P = 0.004), LDL cholesterol (7.09 +/- 12.7%, P = 0.001), cholesterol/HDL cholesterol ratio (3.89 +/- 11.7%, P = 0.015), and free thyroxine (2.50 +/- 8.47%, P = 0.004). No significant change occurred in HDL cholesterol, triglycerides, weight, blood pressure, creatinine, dehydroepiandrosterone sulfate, androstenedione, and the hypothalamic-pituitary-ovarian axis hormones.

Conclusions: These results show that dietary supplementation with soy phytoestrogens favorably alters insulin resistance, glycemic control, and serum lipoproteins in postmenopausal women with type 2 diabetes, thereby improving their cardiovascular risk profile.

Publication types

  • Clinical Trial
  • Comparative Study
  • Randomized Controlled Trial

MeSH terms

  • Blood Glucose / metabolism*
  • Blood Pressure
  • Body Weight
  • Cardiovascular Diseases / prevention & control
  • Cross-Over Studies
  • Diabetes Mellitus, Type 2 / blood
  • Diabetes Mellitus, Type 2 / drug therapy*
  • Diabetic Angiopathies / prevention & control
  • Dietary Supplements
  • Double-Blind Method
  • Estrogens, Non-Steroidal / administration & dosage
  • Estrogens, Non-Steroidal / therapeutic use*
  • Female
  • Glycated Hemoglobin A / metabolism
  • Hormones / blood
  • Humans
  • Isoflavones*
  • Lipids / blood*
  • Patient Compliance
  • Patient Selection
  • Phytoestrogens
  • Phytotherapy*
  • Placebos
  • Plant Preparations
  • Postmenopause*
  • Soybeans

Substances

  • Blood Glucose
  • Estrogens, Non-Steroidal
  • Glycated Hemoglobin A
  • Hormones
  • Isoflavones
  • Lipids
  • Phytoestrogens
  • Placebos
  • Plant Preparations