Effects of Soymilk on Serum Insulinemic Status and High Sensitivity C-Reactive Protein Levels in Healthy Postmenopausal Women of Bangladesh

Abstract

Background: Postmenopausal women are at increased risk for cardiac diseases because many risk factors are aggravated by menopause. Isoflavones are phytoestrogens present in natural sources, and they may modulate risk factors favorably, involving mechanisms similar to estrogen. The study aimed to assess the effects of soymilk on serum insulinemic status and hs-C reactive protein (CRP) levels of postmenopausal women of Bangladesh. Methods: Thirty-six women (aged 50 ± 5 years, M ± SD) participated in a randomized, un-blind, open-ended, crossover study design for 52 days. During the study period, the patients made four visits (before and after the intervention including the washout period). The soymilk group consumed 350 mL of milk twice a day for 21 days; the milk contained ~30 mg of isoflavones. Fasting blood glucose (FBG), postprandial glucose (PPG), HbA1c, serum insulin, and hs-CRP were measured on day 0, day 21, day 31, and day 51 with a 10-day washout period. Paired t-test was performed to determine the effects of soymilk on the CVD risks among postmenopausal women and a student t-test was performed for group comparison. Statistical tests were considered significant at p value of ≤0.05. Results: The mean (±SD) BMI of the postmenopausal women was 25.14 ± 3.55 kg/m2. In the consumption of soymilk no significant changes were found in glycemic, insulinemic, and hs-CRP levels between and within the groups. After crossover, a significant change was observed in FBG (5.18 ± 0.49 vs 5.56 ± 0.43, p = 0.005) in the soymilk group. No significant changes were observed in other parameters within or between the groups. However, FBG and hs-CRP levels were found to improve but not significantly at the end of 51 days. Conclusions: Soy isoflavones did not improve serum insulinemic status and hs-C reactive protein (CRP) levels among Bangladeshi postmenopausal women. Further studies need to be elucidated by considering a follow-up study with a large sample size.