Effect of dietary intervention on serum lignan levels in pregnant women - a controlled trial

Riitta Luoto,Elham Kharazmi,Niina M Saarinen,Sari Mäkelä,Mahdi Fallah,Jani Raitanen,Leena Hilakivi-Clarke,Annika I Smeds

doi:10.1186/1742-4755-7-26

Abstract

BackgroundMother's diet during pregnancy is important, since plant lignans and their metabolites, converted by the intestinal microflora to enterolignans, are proposed to possess multiple health benefits. Aim of our study was to investigate whether a dietary intervention affects lignan concentrations in the serum of pregnant women.MethodsA controlled dietary intervention trial including 105 first-time pregnant women was conducted in three intervention and three control maternity health clinics. The intervention included individual counseling on diet and on physical activity, while the controls received conventional care. Blood samples were collected on gestation weeks 8-9 (baseline) and 36-37 (end of intervention). The serum levels of the plant lignans 7-hydroxymatairesinol, secoisolariciresinol, matairesinol, lariciresinol, cyclolariciresinol, and pinoresinol, and of the enterolignans 7-hydroxyenterolactone, enterodiol, and enterolactone, were measured using a validated method.ResultsThe baseline levels of enterolactone, enterodiol and the sum of lignans were higher in the control group, whereas at the end of the trial their levels were higher in the intervention group. The adjusted mean differences between the baseline and end of the intervention for enterolactone and the total lignan intake were 1.6 ng/ml (p = 0.018, 95% CI 1.1-2.3) and 1.4 ng/mg (p = 0.08, 95% CI 1.0-1.9) higher in the intervention group than in the controls. Further adjustment for dietary components did not change these associations.ConclusionThe dietary intervention was successful in increasing the intake of lignan-rich food products, the fiber consumption and consequently the plasma levels of lignans in pregnant women.Trial registrationISRCTN21512277, http://www.isrctn.org

Highlights

During pregnancy, the fetus is exposed to multiple biologically active compounds that originate from the maternal diet
The present study was conducted at six volunteering clinics in the city of Tampere and the town of Hämeenlinna, both located in the southern Finland
Among the women in the intervention group, the concentration of almost all serum lignans increased during intervention, while among the controls the serum concentrations of lignans other than enterolactone either did not change or they were reduced

Summary

Introduction

The fetus is exposed to multiple biologically active compounds that originate from the maternal diet. Some of these may affect offspring’s later health. In the Western diet, phytoestrogens consist mainly of plant lignans, which are a large group of fiber-associated phenolic compounds, widely distributed in edible plants, e.g., seeds, whole grains, vegetables, fruits and berries [2,3]. Significant dietary sources of fiber-associated phenolic compounds are beverages such as coffee, tea, and red wine [2,3]. Mother’s diet during pregnancy is important, since plant lignans and their metabolites, converted by the intestinal microflora to enterolignans, are proposed to possess multiple health benefits. Aim of our study was to investigate whether a dietary intervention affects lignan concentrations in the serum of pregnant women

Methods

Results

Conclusion