Journal Article

Effects of isoflavone-containing soya protein on ex vivo cholesterol efflux, vascular function and blood markers of CVD risk in adults with moderately elevated blood pressure: a dose–response randomised controlled trial

Krul, Elaine S., Fleming, Jennifer A., Kris-Etherton, Penny M., Skulas-Ray, Ann C., Richter, Chesney K., Link, Christina J., Mukherjea, Ratna

2017

Overview

Emerging CVD risk factors (e.g. HDL function and central haemodynamics) may account for residual CVD risk experienced by individuals who meet LDL-cholesterol and blood pressure (BP) targets. Recent evidence suggests that these emerging risk factors can be modified by polyphenol-rich interventions such as soya, but additional research is needed. This study was designed to investigate the effects of an isoflavone-containing soya protein isolate (delivering 25 and 50 g/d soya protein) on HDL function (i.e. ex vivo cholesterol efflux), macrovascular function and blood markers of CVD risk. Middle-aged adults (n 20; mean age=51·6 (sem 6·6) years) with moderately elevated brachial BP (mean systolic BP=129 (sem 9) mmHg; mean diastolic BP=82·5 (sem 8·4) mmHg) consumed 0 (control), 25 and 50 g/d soya protein in a randomised cross-over design. Soya and control powders were consumed for 6 weeks each with a 2-week compliance break between treatment periods. Blood samples and vascular function measures were obtained at baseline and following each supplementation period. Supplementation with 50 g/d soya protein significantly reduced brachial diastolic BP (−2·3 mmHg) compared with 25 g/d soya protein (Tukey-adjusted P=0·03) but not the control. Soya supplementation did not improve ex vivo cholesterol efflux, macrovascular function or other blood markers of CVD risk compared with the carbohydrate-matched control. Additional research is needed to clarify whether effects on these CVD risk factors depend on the relative health of participants and/or equol producing capacity.

• Publisher: Cambridge University Press
• Subject: Adult / Adults / Arteriosclerosis - drug therapy / Biomarkers / blood / Blood pressure / blood sampling / Carbohydrates / Cardiovascular Diseases - blood / Cholesterol / Cholesterol - metabolism / compliance / cross-over studies / dose response / Efflux / Evidence-based medicine / Female / Hemodynamics / High density lipoprotein / Human and Clinical Nutrition / Humans / Hypertension / Hypertension - blood / Isoflavones / Isoflavones - chemistry / Lipids / Low density lipoprotein / low density lipoprotein cholesterol / Male / Markers / Middle Aged / middle-aged adults / powders / protein isolates / Randomization / randomized clinical trials / Risk analysis / Risk Factors / Risk management / Soy products / soy protein / Soybean Proteins - chemistry / Soybean Proteins - pharmacology / Supplements / Womens health