Send to

Choose Destination
See comment in PubMed Commons below
Nutr Res. 2013 Dec;33(12):1026-33. doi: 10.1016/j.nutres.2013.08.009. Epub 2013 Sep 18.

Soy proteins and isoflavones reduce interleukin-6 but not serum lipids in older women: a randomized controlled trial.

Author information

  • 1Department of Nutritional Sciences, University of Connecticut, Storrs, CT; Institute for Aging Research, Hebrew SeniorLife, Harvard Medical School, Boston, MA.


Soy foods contain several components, notably, isoflavones and amino acids, that may improve cardiovascular health. We evaluated the long-term effect of soy protein and/or soy isoflavones supplementation on serum lipids and inflammatory markers using a 1-year randomized, double-blind, placebo-control, clinical trial in 131 healthy ambulatory women older than 60 years. We hypothesized that soy protein, in combination with isoflavones, would have the largest positive effect on coronary heart disease risk factors (serum lipids and inflammatory markers) compared with either intervention alone and that, within groups receiving isoflavones, equol producers would have more positive effects on coronary heart disease risk factors than nonequol producers. After a 1-month baseline period, participants were randomized into 1 of 4 intervention groups: soy protein (18 g/d) and isoflavone tablets (105 mg/d isoflavone aglycone equivalents), soy protein and placebo tablets, control protein and isoflavone tablets, or control protein and placebo tablets. T Tests were used to assess differences between equol and nonequol producers. Ninety-seven women completed the trial. Consumption of protein powder and isoflavone tablets did not differ among groups, and compliance with study powder and tablets was 79% and 90%, respectively. After 1 year, in the entire population, there were either no or little effects on serum lipids and inflammatory markers, regardless of treatment group. Equol producers, when analyzed separately, had significant improvements in total cholesterol/high-density lipoprotein and low-density lipoprotein/high-density lipoprotein ratios (-5.9%, P = .02; -7.2%, P = .04 respectively). Soy protein and isoflavone (either alone or together) did not impact serum lipids or inflammatory markers. Therefore, they should not be considered an effective intervention to prevent cardiovascular disease because of lipid modification in healthy late postmenopausal women lacking the ability to produce equol.


ANOVA; BMI; CHD; CVD; Cardiovascular health; Equol producer; HDL; IL-6; LDL; Postmenopausal women; Serum lipids; Soy isoflavones; Soy protein; TC; TG; analysis of variance; body mass index; cardiovascular disease; coronary heart disease; high-density lipoprotein; high-sensitivity C-reactive protein; hsCRP; interleukin-6; low-density lipoprotein; total cholesterol; triglycerides

[PubMed - indexed for MEDLINE]
Free PMC Article
PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Elsevier Science Icon for PubMed Central
    Loading ...
    Support Center