Soy protein supplementation does not cause lymphocytopenia in postmenopausal women

Soung, Patade Anagha, Khalil, Lucas, Devareddy Latha, Greaves, Arjmandi

Description

The health benefits of soy isoflavones have been widely investigated; however, there are some concerns as to whether soy isoflavones, similar to ipriflavone, a synthetic isoflavone, cause lymphocytopenia in postmenopausal women. Hence, the purpose of this study was to investigate the extent to which 12-month supplementation of 25 g soy protein containing 60 mg isoflavones alters lymphocyte counts or other hematological parameters in postmenopausal women who were not on hormone replacement therapy. Methods Eighty-seven postmenopausal women were randomly assigned to receive either soy protein or an equivalent amount of control protein devoid of isoflavones. Fasting venous blood was collected at baseline and at the end of twelve month study period for complete blood count analyses. Results Between the two treatment groups, the percent changes in hematological parameters, including lymphocytes, were not different. While women consuming the soy supplement had an increase in mean corpuscular hemoglobin concentration (MCHC) and red cell distribution width index (RDW; a marker of reticulocytes), women consuming the control diet had higher percentage of only MCHC. Conclusion Overall, the results of the present study indicate that consumption of 25 g soy protein containing 60 mg isoflavones daily for one year does not cause lymphocytopenia.

Informations

• Publié par: biomed
• Publié le: 01 janvier 2006
• Nombre de lectures: 2
• Langue: English

Extrait

Nutrition Journal

BioMedCentral

Open Access Research Soy protein supplementation does not cause lymphocytopenia in postmenopausal women 2 2 22 Do Y Soung, Anagha Patade, Dania A Khalil, Edralin A Lucas, 1 31 Latha Devareddy, Kathryn A Greavesand Bahram H Arjmandi*

1 2 Address: Departmentof Nutrition, Food and Exercise Sciences, Florida State University, Tallahassee, FL, USA,Department of Nutritional 3 Sciences, Oklahoma State University, Stillwater, OK, USA andThe Solae Company, St. Louis, MO, USA Email: Do Y Soung  [e-mail]; Anagha Patade  [e-mail]; Dania A Khalil  [e-mail]; Edralin A Lucas  [e-mail]; Latha Devareddy  [e-mail]; Kathryn A Greaves  [e-mail]; Bahram H Arjmandi*  [e-mail] * Corresponding author

Published: 11 April 2006Received: 10 November 2005 Accepted: 11 April 2006 Nutrition Journal2006,5:12 doi:10.1186/1475-2891-5-12 This article is available from: http://www.nutritionj.com/content/5/1/12 © 2006 Soung et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract Background:The health benefits of soy isoflavones have been widely investigated; however, there are some concerns as to whether soy isoflavones, similar to ipriflavone, a synthetic isoflavone, cause lymphocytopenia in postmenopausal women. Hence, the purpose of this study was to investigate the extent to which 12-month supplementation of 25 g soy protein containing 60 mg isoflavones alters lymphocyte counts or other hematological parameters in postmenopausal women who were not on hormone replacement therapy. Methods:Eighty-seven postmenopausal women were randomly assigned to receive either soy protein or an equivalent amount of control protein devoid of isoflavones. Fasting venous blood was collected at baseline and at the end of twelve month study period for complete blood count analyses. Results:Between the two treatment groups, the percent changes in hematological parameters, including lymphocytes, were not different. While women consuming the soy supplement had an increase in mean corpuscular hemoglobin concentration (MCHC) and red cell distribution width index (RDW; a marker of reticulocytes), women consuming the control diet had higher percentage of only MCHC. Conclusion:Overall, the results of the present study indicate that consumption of 25 g soy protein containing 60 mg isoflavones daily for one year does not cause lymphocytopenia.

Background Soy protein has been reported to have positive effects on cardiovascular [13] and skeletal health [47] in postmen opausal women. These health benefits of soy can be, in part, attributed to its isoflavone content. For example, genistein, the major isoflavone in soy, has been shown to

improve cardiovascular health by modulating lipid pro file and improving endothelial function in postmenopau sal women [13]. In terms of effects on bone, oneyear supplementation of the isolated isoflavone, genistein, has been reported to significantly enhance bone mineral den sity of femur and lumbar spine in early postmenopausal

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