Original Communication
European Journal of Clinical Nutrition (2005) 59, 843–850. doi:10.1038/sj.ejcn.1602151 Published online 18 May 2005
Effects of soy supplementation on blood lipids and arterial function in hypercholesterolaemic subjects
Guarantor: K Hermansen.
Contributors: KH and AA were the daily project leaders, were involved in the study scheme and data interpretation, and wrote the manuscript together with BH. BH, RJ, MD, and EP were involved in carrying out the study and provided significant advice. PC carried out the investigation of the arterial function and interpretation of the data. BD was involved in the study scheme and data interpretation, and provided significant advice. JJH performed analyses of GLP-1 and GIP, was involved in data interpretation and provided significant advice.
K Hermansen1, B Hansen2, R Jacobsen2, P Clausen3, M Dalgaard1, B Dinesen4, J J Holst5, E Pedersen1 and A Astrup2
- 1Department of Endocrinology and Metabolism C, Aarhus University Hospital, Aarhus, Denmark
- 2Department of Human Nutrition, Centre of Advanced Food Research, The Royal Veterinary and Agricultural University, Frederiksberg, Denmark
- 3Department of Clinical Biochemistry, Copenhagen County Hospital, Gentofte, Denmark
- 4Nutri Pharma ASA, Oslo, Norway
- 5Department of Medical Physiology, The Panum Institute, University of Copenhagen, Denmark
Correspondence: K Hermansen, Department of Endocrinology and Metabolism, Aarhus University Hospital, Aarhus Sygehus THG, Tage-Hansens Gade 2, DK-8000 Aarhus C, Denmark. E-mail: Kjeld.Hermansen@dadlnet.dk
Received 27 October 2004; Revised 17 January 2005; Accepted 25 February 2005; Published online 18 May 2005.
Abstract
Background:
Studies on soy supplementation suggest a cardioprotective potential.
Objective:
To examine the effects on LDL cholesterol and arterial function as a result of dietary enrichment with soy supplementation.
Design:
A Randomized, double blind, parallel intervention trial.
Setting:
Department of Endocrinology and Metabolism C, Aarhus University Hospital, and Department of Human Nutrition, The Royal Veterinary and Agricultural University, Denmark.
Subjects:
In all, 100 hypercholesterolaemic but otherwise healthy subjects were included in the study of which 89 completed it.
Interventions:
Subjects were randomly assigned to 24 weeks of daily intake of either a soy supplement, Abalon® (30 g soy protein, 9 g cotyledon fibre and 100 mg isoflavones) or placebo (30 g of casein). The soy supplement and placebo were provided in two sachets daily that were stirred in water. Fasting plasma lipids, TNF-
, homocysteine, insulin sensitivity, homeostasis model assessment (HOMA-IR), serum insulin, serum glucose, blood pressure as well as Glucagon-like peptide 1 (GLP-1), glucose-dependent insulinotropic peptide (GIP) and plasma lipids to a fat-rich meal were recorded before and after the intervention. In a sub study in 32 subjects, arterial dilatory capacity, compliance, and distensibility were recorded before and after the intervention.
Results:
In the main study, no difference in fasting plasma lipid levels or insulin sensitivity was found between soy-based supplement and placebo. A significant postprandial increase in GIP to the meal test was observed in the soy group (P<0.05). In a substudy, no difference between the groups in changes in flow-mediated vasodilatation (P=0.84) was detected, while the soy supplementation caused a reduction in LDL and total cholesterol.
Conclusions:
No significant effects on blood lipids were observed in the main study to a soy supplementation in hypercholesterolaemic subjects after 24 weeks. In the substudy, the soy supplementation, however, reduced LDL and total cholesterol but did not influence markers of arterial function.
Sponsorship:
Nutri Pharma ASA, Oslo, Norway.
Keywords:
soy, lipoproteins, postprandial lipaemia, insulin sensitivity, incretins, endothelial function